The study, led by Paul Wasuwanich of Mount Carmel Health System and the University of Florida College of Medicine, together with maternal-fetal medicine specialist Tony S. Wen and pediatric hepatologist Wikrom Karnsakul of Johns Hopkins University School of Medicine, drew on the National Inpatient Sample, the largest publicly available database of hospital discharges in the United States. Using standardized ICD-9 and ICD-10 diagnostic codes, the researchers extracted records of pregnant women hospitalized with hepatitis B and hepatitis delta over the 24-year study window. They then compared demographic characteristics, comorbid conditions, pregnancy complications, fetal outcomes, and mortality between two cohorts: women infected with hepatitis B virus alone and women co-infected with hepatitis B and hepatitis delta viruses.

The virology underlying this comparison is central to why the question matters. Hepatitis delta virus is a defective RNA virus that cannot complete its life cycle without hepatitis B virus, which supplies the envelope proteins the delta virion needs to assemble and spread. Because of this absolute dependence, delta infection occurs only in people who already harbor hepatitis B, either as a simultaneous co-infection or as a superinfection laid on top of chronic hepatitis B. Superinfection in particular is notorious for driving fulminant hepatitis in acute settings and for accelerating the progression of chronic liver disease toward cirrhosis and hepatocellular carcinoma. Despite this severity, pregnant patients with delta infection have been so scarcely studied that no specific clinical guidance exists for managing the combination during gestation.

From the nationwide dataset, the investigators identified 390 pregnancies affected by hepatitis delta co-infection and 127,332 pregnancies with hepatitis B alone. The delta cohort was young, with a median age of 30 years, and the predominant racial and ethnic group was Asian or Pacific Islander, accounting for 27.4 percent of cases, a distribution consistent with the global epidemiology of hepatitis B, which is endemic across much of Asia and the Pacific islands. Notably, there were no maternal deaths recorded in the delta group during the study period, a reassuring finding given the virus’s fearsome reputation in nonpregnant populations.

When the researchers examined liver-related comorbidities, the differences between the cohorts became apparent. Hepatitis C co-infection was roughly three times more common among women with delta infection, occurring in 12.1 percent of the delta cohort versus 4.1 percent of the hepatitis B-only group, a difference that was highly statistically significant. Cirrhosis, the advanced scarring of the liver that represents the end stage of chronic viral hepatitis, was also significantly more frequent in the delta cohort, affecting 1.3 percent of these pregnant women compared with just 0.2 percent of those with hepatitis B alone. These figures, though small in absolute terms, align with the established biology of delta superinfection, which is known to accelerate hepatic fibrosis and push patients toward cirrhosis at younger ages than hepatitis B alone.

Not every measured variable diverged between the groups. Rates of diabetes, obesity, HIV infection, intravenous drug use, coagulopathy, and thrombocytopenia were statistically similar across both cohorts, suggesting that the excess liver disease seen in the delta group was not simply a reflection of a generally sicker patient population. This pattern of findings strengthens the interpretation that the delta virus itself, rather than confounding comorbidities, drives the additional hepatic burden observed in these pregnancies.

The fetal outcomes formed the most consequential part of the analysis. Of the 390 pregnancies in the delta cohort, 318, or 81.5 percent, had a known delivery outcome recorded. Among these, stillbirth occurred in 2.8 percent of delta-affected pregnancies, compared with 0.7 percent of pregnancies with hepatitis B alone, a difference that reached statistical significance. In other words, women carrying both viruses faced roughly a fourfold higher rate of stillbirth than women carrying hepatitis B alone. By contrast, the rates of preterm birth and post-term birth did not differ significantly between the two groups, indicating that the adverse effect of delta co-infection on fetal outcomes was concentrated in fetal loss rather than in altered timing of delivery.

The authors conclude that hepatitis delta remains uncommon in pregnancy but is likely under-recognized, and that pregnancies affected by concurrent hepatitis B and delta infection may carry a higher risk of adverse fetal outcomes, particularly stillbirth, compared with hepatitis B alone. The under-recognition point deserves emphasis: because delta testing is not routinely performed in all hepatitis B-positive pregnant patients, the true prevalence of co-infection in this population may exceed what hospital discharge data capture, and the 390 identified cases likely represent a floor rather than a ceiling.

The study’s methodology carries both strengths and limitations worth noting. The National Inpatient Sample offers an unmatched scale for studying rare conditions, pooling discharge data from thousands of hospitals to assemble a cohort large enough for meaningful statistical comparison. However, the database relies on administrative coding, which can miss diagnoses, and it captures only hospitalized patients, meaning milder cases managed in outpatient settings would not appear. The researchers analyzed the data using chi-square tests for categorical comparisons and logistic regression to adjust for potential confounders, and the study was approved as exempt by the institutional review board of the University of Florida College of Medicine under the Declaration of Helsinki.

For clinicians, the practical message is that hepatitis B-positive pregnant women, particularly those from regions where delta virus is endemic or those with risk factors such as injection drug use, may warrant screening for hepatitis delta so that heightened surveillance of fetal well-being can be considered. For researchers, the findings open a clear agenda: prospective studies with virologically confirmed delta infection, detailed gestational timing of infection, and longitudinal follow-up of offspring are needed to confirm the stillbirth signal and to establish whether antiviral strategies targeting hepatitis B, which would also suppress the delta helper virus, can mitigate the fetal risk. In the meantime, this 24-year nationwide analysis stands as the most comprehensive portrait yet of a neglected intersection between severe viral hepatitis and pregnancy.

Subject of Research: Outcomes of hepatitis B and hepatitis delta co-infection in hospitalized pregnant women in the United States

Article Title: Outcomes of hepatitis B and hepatitis delta infection in hospitalized pregnant women in the United States: a nationwide study, 1998–2022

Article References: Wasuwanich, P., Wen, T. S., & Karnsakul, W. (2026). Outcomes of hepatitis B and hepatitis delta infection in hospitalized pregnant women in the United States: a nationwide study, 1998–2022. BMC Infectious Diseases. https://doi.org/10.1186/s12879-026-14406-z

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14406-z

Keywords: hepatitis B, hepatitis delta, pregnancy, stillbirth, cirrhosis, viral hepatitis, National Inpatient Sample, hepatitis C, fetal outcomes, maternal health, liver disease, epidemiology

The review, led by Muhammad Hassan Saeed and colleagues working across institutions in Pakistan and Somalia, was conducted in accordance with the PRISMA 2020 reporting guideline and prospectively registered in PROSPERO (CRD420251137112). The investigators searched PubMed/MEDLINE, Embase, Scopus, the Cochrane Library, Google Scholar, and ClinicalTrials.gov, completing the original searches in August 2025 and re-searching all information sources on September 21, 2026, to capture any newly published eligible trials. Their objective was precise: to compare the efficacy and safety of bulevirtide monotherapy against bulevirtide combined with Peg-IFNα-2a in adults with chronic hepatitis D. Only randomized controlled trials directly comparing the two strategies were eligible, ensuring that the synthesis rested on the highest tier of interventional evidence rather than observational cohorts or single-arm studies.

The methodological rigor of the analysis deserves particular attention because it reflects a broader shift in how meta-analysts handle small trials. The primary analyses used restricted maximum likelihood (REML) estimation with the Hartung–Knapp–Sidik–Jonkman (HKSJ) adjustment, a random-effects approach that widens confidence intervals when the number of studies is small and between-trial heterogeneity is uncertain, thereby guarding against the overconfident estimates that conventional methods can produce. As sensitivity analyses, the team also ran DerSimonian–Laird (DL) random-effects models with conventional normal-approximation confidence intervals. Outcomes synthesized included trial-defined virological, biochemical, and combined responses, as well as continuous changes in HDV RNA and alanine aminotransferase (ALT), the liver enzyme that serves as a surrogate marker for inflammatory activity. Standardized mean differences were expressed as Hedges’ g, and binary outcomes as risk ratios (RR).

Three randomized controlled trials comprising 225 patients met the inclusion criteria. At week 24, virological response was numerically higher with the combination regimen, but the difference was not statistically significant under the primary analysis (RR 2.07, 95% CI 0.38–11.40), and combined response showed essentially no difference (RR 1.01, 95% CI 0.12–8.48). Combination therapy did, however, produce a significantly greater reduction in HDV RNA (Hedges’ g −0.96, 95% CI −1.75 to −0.18), indicating deeper viral suppression during the first six months of treatment. In contrast, biochemical response favored bulevirtide monotherapy (RR 0.36, 95% CI 0.17–0.78), as did the ALT change (mean difference 45.58 U/L, 95% CI 33.51–57.65), meaning that patients on the combination were less likely to achieve normalized liver enzymes while on treatment.

The picture changed at week 48. By that point, virological response clearly favored the combination regimen (RR 5.33, 95% CI 1.57–18.12), suggesting that the interferon-containing strategy delivers superior viral control with longer exposure, even though biochemical and combined responses did not differ significantly between the groups at this time point. The divergence between viral and biochemical endpoints is scientifically noteworthy: HDV RNA suppression and ALT normalization do not always move in lockstep, and the mechanisms underlying this dissociation—whether interferon’s immunomodulatory effects, bulevirtide’s entry-blocking pharmacodynamics, or trial-specific response definitions—remain an open question for hepatologists designing future trials.

Post-treatment durability emerged as another key dimension. At 24 weeks after the end of treatment (EOT), combined response favored combination therapy (RR 4.15, 95% CI 1.05–16.40), while the virological and biochemical response estimates remained imprecise, with confidence intervals too wide to support firm conclusions. Sustained off-treatment response is the ultimate goal in chronic hepatitis D, since relapse after stopping therapy is common, and the finding that the combination arm maintained an advantage in combined endpoints at this late stage will inform discussions about treatment duration and discontinuation strategies. Nevertheless, the authors emphasize that these longer-term estimates rested on only two randomized trials, limiting the reliability of the post-treatment synthesis.

Safety signals tracked the known toxicity profile of interferon. Regimens containing Peg-IFNα-2a were associated with higher rates of neutropenia and thrombocytopenia, the hematologic adverse effects that have long constrained interferon use in viral hepatitis. Bulevirtide itself has generally been well tolerated in clinical practice, with the most frequently reported adverse effect being injection-site reactions and, in some studies, transient elevations in bile acids. The meta-analysis thus frames the central clinical trade-off: deeper viral suppression and better sustained combined responses with the combination, at the cost of interferon-related hematologic toxicity and less favorable on-treatment liver enzyme responses.

A technically important caveat concerns the statistical method itself. The DL sensitivity analyses yielded narrower confidence intervals for several outcomes and changed the statistical significance of some longer-term estimates, illustrating how method choice can alter conclusions in meta-analyses built on very few trials. The HKSJ adjustment, which the authors treated as primary, is specifically designed for settings with fewer than five studies, where the conventional DL approach with normal-approximation intervals can be anticonservative. The fact that significance flipped for some endpoints between methods is not a flaw of the review but a faithful reflection of the fragility of the underlying randomized evidence, and it underscores why the authors call for cautious interpretation, particularly for longer-term and post-treatment outcomes.

The authors declare no competing interests and received no funding for the study, and the work is published open access under a Creative Commons Attribution 4.0 license. For clinicians managing chronic hepatitis D, the review provides a technically grounded evidence base: bulevirtide plus Peg-IFNα-2a was associated with greater virological suppression at week 48 and better combined responses 24 weeks after treatment ended, whereas bulevirtide monotherapy showed more favorable on-treatment biochemical responses and avoided interferon-related cytopenias. With only three trials and 225 patients, and wide confidence intervals under the primary REML-HKSJ analysis, the randomized evidence remains limited. Larger, longer randomized trials with standardized endpoint definitions will be needed to determine the optimal position of combination therapy in chronic hepatitis D, particularly as bulevirtide dosing strategies, treatment duration, and off-treatment durability continue to evolve in this rare and devastating disease.

Subject of Research: Virology

Article Title: Bulevirtide with or without Peg-IFNα-2a for chronic hepatitis D: a systematic review and meta-analysis of randomized controlled trials

Article References: Saeed, M. H., Lohana, K. C., Kashish, F. N. U., Nadeem, U., Dadabhoy, S. J., Ahsan, A. E., Zafar, H., Rizvi, S. E. Z., Bux, A., Butt, N., Jama, M. M., & Shaikh, M. A. (2026). Bulevirtide with or without Peg-IFNα-2a for chronic hepatitis D: a systematic review and meta-analysis of randomized controlled trials. BMC Infectious Diseases. https://doi.org/10.1186/s12879-026-14668-7

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14668-7

Keywords: chronic hepatitis D, bulevirtide, pegylated interferon alfa-2a, HDV RNA suppression, NTCP inhibitor, meta-analysis, randomized controlled trials, viral hepatitis, liver disease, antiviral therapy, without, Peg-IFN

The original analysis, published earlier in 2026 in the same journal under the title Untangling the Web of Hepatitis C Risk in Rural Communities, drew on the authors’ combined expertise in behavioral science, community health education, and clinical medicine. Bailey, who leads the correspondence from the Center on Drug and Alcohol Research at the University of Kentucky, has spent her career examining how substance use environments drive infectious disease transmission in Appalachia and similar regions. Tarplin brings a public health perspective on how community-level education and prevention infrastructure function, while Kang contributes the clinical vantage point of a physician-scientist embedded in pediatric and general care systems. Together, the three argued that hepatitis C in rural areas follows a distinctive epidemiological pattern shaped by limited treatment capacity, dispersed populations, and the evolving landscape of injection drug use.

The technical core of their argument rests on the recognition that hepatitis C virus, a blood-borne RNA virus of the Flaviviridae family, spreads efficiently through even small-volume blood exposures. In urban contexts, transmission has historically clustered around dense networks of people who inject drugs, prison systems, and specific healthcare lapses. Rural settings invert many of these assumptions. Population dispersion means that risk networks are geographically stretched, yet socially tight: a small number of individuals may connect otherwise distant counties through shared equipment, transportation routes, or drug supply chains. The authors contend that standard surveillance models, calibrated to urban outbreak dynamics, systematically underestimate how quickly infection can propagate across a rural county once introduced.

Compounding this structural vulnerability is the well-documented shortage of primary care capacity in rural America. The authors anchor their reply in the framework established by the National Academies of Sciences, Engineering, and Medicine’s 2021 consensus report, Implementing High-Quality Primary Care: Rebuilding the Foundation of Health Care, which they cite as a foundational reference. That report characterized primary care as the only component of the health system for which universal continuous coverage produces better population health outcomes, and it warned that the erosion of rural primary care infrastructure undermines every downstream preventive service. For hepatitis C, the implications are direct: screening for the virus, linkage to curative antiviral therapy, and harm-reduction counseling all depend on a functioning primary care layer that many rural counties lack entirely.

The second pillar of the authors’ evidence base is a 2024 synthesis published in BMC Primary Care by Endalamaw and colleagues, which systematically reviewed barriers and strategies for primary health care workforce development. That synthesis identified chronic workforce shortages, maldistribution of trained clinicians, and weak retention mechanisms as persistent obstacles to primary care delivery in underserved areas. Bailey, Tarplin, and Kang invoke this literature to argue that hepatitis C elimination targets in rural regions are not primarily limited by virology or pharmacology. Direct-acting antiviral regimens cure more than 95 percent of chronic infections in as little as eight to twelve weeks of oral therapy. The bottleneck, they maintain, is the human infrastructure required to identify infected individuals, initiate treatment, and prevent reinfection and onward transmission.

The exchange that prompted the response letter illustrates how contested these interpretive frameworks remain. A prior letter to the editor had challenged elements of the original analysis, and the authors’ reply, published under the title Response to Re: Untangling the Web of Hepatitis C Risk in Rural Communities, defends their framing while engaging the critique on its merits. Scientific correspondence of this kind serves a technical function beyond academic courtesy: it forces explicit articulation of the causal assumptions underlying risk models, exposes points of disagreement about data interpretation, and refines the conceptual vocabulary that future empirical studies will inherit. In infectious disease epidemiology, where models of transmission dynamics directly inform resource allocation, such exchanges carry practical weight.

The stakes of this debate are grounded in a sober epidemiological reality. Hepatitis C virus chronically infects an estimated 2.4 million people in the United States, and the opioid-driven injection drug use crisis that intensified after 2010 produced sharp increases in acute hepatitis C incidence precisely in the rural counties least equipped to respond. The virus’s biology amplifies the challenge: most acute infections are asymptomatic or mildly symptomatic, allowing silent propagation through networks before clinical detection. Chronic infection, if untreated, progresses over decades toward hepatic fibrosis, cirrhosis, and hepatocellular carcinoma. The availability of curative therapy since 2013 transformed the disease into an elimination target, and the World Health Organization has set goals for viral hepatitis elimination by 2030, but those goals presuppose detection and treatment systems that rural America often cannot assemble.

The authors’ interdisciplinary composition reflects the analytical stance they defend. Bailey’s affiliation with a department of behavioral science and a center on drug and alcohol research signals attention to the behavioral substrate of transmission, the patterns of drug use, equipment sharing, and social network structure that determine where the virus moves. Tarplin’s community health education background foregrounds prevention messaging and the design of interventions that reach dispersed populations. Kang’s clinical position grounds the analysis in the realities of care delivery, where screening protocols, electronic health record triggers, and referral pathways determine whether a positive antibody test becomes a cured patient or a lost opportunity. The letter’s single-sentence contribution statement, crediting all three authors with conceptualization and writing of the original draft, underscores the deliberately integrated character of the argument.

The correspondence also carries methodological implications for how rural health research is conducted and evaluated. The authors’ web metaphor, the image of hepatitis C risk as an interlaced network rather than a linear chain of causes, resists reduction to any single intervention point. A syringe services program addresses one strand; telehealth-based treatment expands another; workforce development strengthens the clinical node; transportation assistance loosens the geographic constraints that bind the network together. The critique and response cycle, by testing which strands bear the most load, helps prioritize interventions empirically rather than ideologically. The authors report no funding associated with the letter and declare no competing interests, and the journal’s editorial process, from submission on 31 July to acceptance on 5 October 2026, moved the exchange into the published record within a single quarter.

What emerges from the exchange is a research agenda rather than a closed argument. The authors’ reply positions rural hepatitis C risk as a problem that demands simultaneous attention to virology, behavioral science, health services organization, and rural sociology, the very subject categories under which the journal indexes the work. As elimination timelines approach, the letter stands as a reminder that the final mile of infectious disease control is rarely a laboratory problem. It is a problem of networks, of geography, of workforce, and of the quiet structural choices that determine whether a curable virus persists in the communities least able to fight it. The technical conversation between Bailey, Tarplin, Kang, and their critics will continue in the literature, but its practical destination is fixed: translating a web of risk into a web of response.

Subject of Research: Hepatitis C virus transmission risk and primary care barriers in rural communities

Article Title: Response to Re: Untangling the Web of Hepatitis C Risk in Rural Communities

Article References: Bailey, A., Tarplin, S., & Kang, A. (2026). Response to Re: Untangling the Web of Hepatitis C Risk in Rural Communities. Journal of General Internal Medicine. https://doi.org/10.1007/s11606-026-10934-1

Image Credits: AI Generated

DOI: 10.1007/s11606-026-10934-1

Keywords: hepatitis C, rural health, primary care, viral hepatitis, infectious disease epidemiology, harm reduction, workforce shortage, opioid crisis, direct-acting antivirals, health disparities, correspondence, public health

The study enrolled 396 long-distance truck drivers aged 18 years and older at the Tunduma border crossing in Songwe Region, southwestern Tanzania. Participants answered a structured questionnaire administered through the Kobo Toolbox digital platform, covering sociodemographic characteristics, sexual behaviour, occupational history, and health-related factors. Each participant then provided a blood sample, which was tested for hepatitis B surface antigen using the Abbott Determine rapid diagnostic test, a widely deployed immunochromatographic assay that detects the viral surface protein circulating in serum or plasma. The research team analysed the data using bivariate and multivariable logistic regression, reporting adjusted odds ratios with 95 percent confidence intervals to identify which factors remained independently associated with infection after accounting for confounders.

The headline number from the study is a prevalence of 6.6 percent, with a 95 percent confidence interval of 4.3 to 9.5 percent. In absolute terms, 26 of the 396 drivers tested positive for hepatitis B surface antigen. The participants had a median age of 37.5 years with an interquartile range of 13 years, and the overwhelming majority, 308 drivers or 77.8 percent, were married. That a substantial fraction of a largely married, adult male workforce carries an active hepatitis B infection has implications well beyond the individuals concerned, because hepatitis B virus is efficiently transmitted through sexual contact, contaminated blood, and perinatal exposure, meaning an untreated infection in a mobile worker can seed new infections in partners and communities along transport corridors.

Hepatitis B virus itself is a partially double-stranded DNA hepadnavirus that targets hepatocytes, the working cells of the liver. After exposure, the virus can establish a chronic infection, particularly when acquired in childhood, and chronic carriers face a lifelong elevated risk of progressive liver fibrosis, cirrhosis, and primary liver cancer. The presence of hepatitis B surface antigen in the blood is the standard screening marker for current infection, distinguishing carriers from people who have cleared the virus or been vaccinated. In sub-Saharan Africa, where the virus is highly endemic and much transmission occurs early in life, prevalence in the general population frequently exceeds the 1 percent threshold that defines high endemicity by a wide margin, and the World Health Organization has made the elimination of viral hepatitis as a public health threat a global target. Yet screening, vaccination coverage, and linkage to antiviral therapy remain patchy across much of the region, and certain occupational groups fall through the cracks of routine health services.

Long-distance truck drivers have long been recognised in epidemiological literature as a bridge population for sexually transmitted infections, including HIV, because of prolonged separation from regular partners, the availability of commercial sex along transport routes, and limited access to consistent healthcare. What the Tunduma study adds is specific, quantified evidence that the same dynamics apply to hepatitis B. In the multivariable analysis, drivers who reported having more than five sexual partners in the previous 12 months had 2.78 times the odds of hepatitis B surface antigen positivity compared with those reporting five or fewer partners, with a 95 percent confidence interval of 1.120 to 6.901 and a p-value of 0.028. This association held after adjustment for other measured variables, strengthening the inference that high partner numbers, rather than some correlated characteristic, drive the excess risk.

The second independent predictor was occupational in nature. Drivers whose transit time exceeded 60 days had 4.62 times the odds of testing positive compared with drivers whose trips lasted between 0 and 30 days, with a 95 percent confidence interval of 1.707 to 12.520 and a p-value of 0.003. Transit time serves as a composite proxy for cumulative exposure on the road: the longer a driver remains away from home, the more border crossings, roadside contacts, and opportunities for unprotected sexual encounters accumulate, and the less likely it is that the driver encounters vaccination or screening services. The magnitude of this association, nearly a fivefold increase in odds, suggests that the structural rhythm of long-haul work itself, not merely individual behaviour, shapes infection risk in this population.

The authors emphasise that these findings point toward concrete, implementable interventions. Strengthening hepatitis B vaccination programmes, expanding screening and confirmatory testing, and building reliable linkage to appropriate clinical care at border posts and other major transport hubs could substantially improve prevention and early detection among mobile workers. Hepatitis B vaccination is highly effective, inducing protective antibodies against the surface antigen in more than 95 percent of healthy adults after a standard three-dose schedule, and vaccinating adults in high-exposure occupations is a recognised strategy in endemic settings. Because the Tunduma study used a rapid diagnostic test as its primary screening tool, positive results would in routine practice require confirmatory testing, and the study protocol itself included counselling and referral of positive participants to health facilities for further evaluation and management, a model that could be institutionalised at border clinics.

The study’s design carries both strengths and limitations worth noting. As a cross-sectional survey, it captures a snapshot of infection status and self-reported behaviour at a single point in time, which means it can identify associations but cannot definitively establish temporal direction; for example, a long transit time may reflect either greater exposure or the characteristics of drivers who take the longest routes. Behavioural data on sexual partners rely on self-report, which is vulnerable to social desirability bias, particularly on sensitive topics. The rapid diagnostic test, while practical for field conditions, has imperfect sensitivity and specificity compared with laboratory-based immunoassays, and the authors appropriately recommend confirmatory testing where indicated. The sample of 396 drivers, however, provides reasonable statistical power, and the multivariable regression framework adjusted for potential confounders in estimating the independent effects of partner number and transit time.

Ethically, the study was approved by the KCMC University Research Ethics Review Committee under approval number UG 65/2026, with permission from the Tunduma Border Hospital administration, and written informed consent was obtained from all participants. Participant information and specimens were handled confidentially using unique study identification numbers, and results were communicated to participants through appropriate confidential channels. Drivers who tested positive were counselled and referred for confirmatory testing and clinical management, while those who tested negative received information on hepatitis B prevention. The research followed the ethical principles of the Declaration of Helsinki, and the authors declared no competing interests and received no external funding for the work.

The broader significance of the Tunduma findings lies in what they reveal about the geography of infectious disease risk. Border posts are not merely administrative checkpoints; they are nodes where mobile populations, commercial networks, and health systems intersect, often at the exact points where health services are weakest. By documenting a 6.6 percent prevalence of active hepatitis B infection among truck drivers and identifying modifiable correlates of that risk, the study gives Tanzanian health authorities and their regional partners a data-driven rationale for embedding hepatitis services into the transport infrastructure itself. If vaccination, screening, and care linkage can be delivered where long-haul drivers actually work, at the border posts and rest stops that define their professional lives, the study suggests that a highly mobile and historically underserved population could be reached with interventions that protect both the drivers and the communities their routes connect.

Subject of Research: Prevalence and risk factors of hepatitis B virus infection among long-distance truck drivers at a Tanzanian border post

Article Title: Prevalence of hepatitis B surface antigen and associated factors among long-distance truck drivers at the Tunduma One-Stop Border Post, Tanzania: a cross-sectional study at Tunduma, Tanzania

Article References: Moses, S., Mwakanyamale, D. A., Magombi, L. J., Felician, F. F., Issangya, E. T., & Kajeguka, D. C. (2026). Prevalence of hepatitis B surface antigen and associated factors among long-distance truck drivers at the Tunduma One-Stop Border Post, Tanzania: a cross-sectional study at Tunduma, Tanzania. BMC Infectious Diseases. https://doi.org/10.1186/s12879-026-14612-9

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14612-9

Keywords: hepatitis B, hepatitis B surface antigen, long-distance truck drivers, Tanzania, border post, prevalence, risk factors, viral hepatitis, occupational health, cross-sectional study, public health, sub-Saharan Africa

The research, led by Isabele Batista Campanhon and Lorena Da Rós Gonçalves, who contributed equally to the work, and supervised by corresponding author Márcia Regina Soares, took advantage of an increasingly popular diagnostic fluid: saliva. Over the last two decades, saliva has emerged as a promising medium for disease detection because its collection is noninvasive, painless, and does not require trained phlebotomists or specialized biohazard handling to the same degree as blood. Advances in nanotechnology-based analytical methods have further enabled the detection of low-abundance biomarkers in oral fluid, making it feasible to search for disease signatures in a matrix that was once considered too dilute and too variable for serious clinical proteomics.

To probe the salivary proteome of infected individuals, the team applied a label-free quantification approach coupled with mass spectrometry to whole saliva samples obtained from patients infected with HBV or HCV and from healthy uninfected controls. The analytical platform combined nanoflow liquid chromatography with tandem mass spectrometry (nLC-MS/MS) using a Linear Ion Trap coupled to an Orbitrap mass analyzer (LTQ Orbitrap), an instrument configuration well suited to resolving complex protein mixtures and identifying peptides with high mass accuracy. Label-free strategies avoid the chemical labeling steps used in some quantitative proteomics workflows, reducing sample handling and allowing a larger number of proteins to be compared across groups, though they demand careful statistical treatment of the resulting intensity data.

That statistical treatment is a notable feature of the study’s design and reporting. The authors identified individual candidate protein biomarkers and analyzed them using nominal p values without correction for multiple testing across proteins. This distinction matters: in proteomic experiments that screen thousands of features simultaneously, unadjusted p values can flag proteins as significant by chance alone, and the researchers were explicit that the false discovery rate values reported in their supplementary material relate to protein identification rather than to differential abundance testing. Group comparisons were carried out with nonparametric tests, including Mann–Whitney U tests for pairwise comparisons and Kruskal–Wallis tests across the three study groups, approaches that do not assume normally distributed data and are commonly used for proteomic intensity measurements that often skew across orders of magnitude.

Within this framework, the analysis revealed a distinctive pattern of protein abundance changes in the saliva of infected patients. One protein stood out for its increased expression: IgG Fc-binding protein, which showed higher levels in infected individuals than in healthy controls. This molecule, associated with mucosal surfaces and with the binding of the Fc portion of immunoglobulin G, is an intriguing candidate in the context of chronic viral infection, where systemic and mucosal antibody responses are continuously engaged. Its elevation in the saliva of HBV- and HCV-infected patients suggests that chronic hepatitis may leave a measurable imprint on the oral immune environment, although the authors present these findings as candidate biomarkers requiring further validation rather than as established diagnostic markers.

In contrast to the elevated IgG Fc-binding protein, several secreted proteins were significantly less abundant in the saliva of infected individuals than in healthy controls. The downregulated group included haptoglobin, prolactin-inducible protein, submandibular gland androgen-regulated protein 3, and complement C3. Each of these proteins has plausible connections to the biology of infection and inflammation. Haptoglobin is an acute-phase protein best known for binding free hemoglobin, and complement C3 is a central component of the complement cascade that bridges innate immunity to pathogen clearance. Prolactin-inducible protein, secreted abundantly by the lacrimal and salivary glands, has been implicated in immune regulation at mucosal sites, and submandibular gland androgen-regulated protein 3 reflects the secretory activity of the major salivary glands themselves. A coordinated decrease in such proteins could reflect alterations in glandular function, systemic inflammatory signaling, or the redistribution of immune proteins during chronic viral disease.

The clinical motivation behind the search for salivary markers is grounded in the limitations of current practice. Liver biopsy, although often regarded as the gold standard diagnostic method for assessing hepatic disease, presents important limitations related to safety, cost, and intraobserver and interobserver variability. Sampling error is inherent to a procedure that extracts only a tiny fragment of a large organ, and the interpretation of histological features can differ between pathologists examining the same specimen. Noninvasive alternatives, from serum fibrosis scores to transient elastography, have reduced reliance on biopsy, but reliable biomarkers for early diagnosis and longitudinal disease monitoring remain an unmet need given the severity of HBV- and HCV-associated diseases. Saliva, if validated, could complement these tools with a sample that patients can provide easily and repeatedly.

The study was approved by the Ethics Committee of the Federal University of Rio de Janeiro (protocol 80709 HUCFF/FM/UFRJ), and written informed consent was obtained from all participating patients. The mass spectrometry analyses were supported by the Mass Spectrometry Laboratory at the Brazilian Biosciences National Laboratory (LNBio), CNPEM-ABTLuS, in Campinas, Brazil, and Dr. Yuri Pereira Souza provided bioinformatics support. The work was funded by the Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ, grant APQ1 E-26/111.770/2012), and Gonçalves received a postdoctoral scholarship from CAPES through its PNPD Institutional Program. The authors declared no competing interests, and the article is published open access under a Creative Commons license.

An important caveat accompanies the findings, and it is one the authors themselves flag in their supplementary documentation: the group-comparison p values were not adjusted for multiple testing across proteins. This means the reported candidates should be viewed as hypotheses generated by an exploratory inter-individual variation study rather than as confirmed diagnostic markers. The inter-individual component of the study’s title is also instructive, acknowledging that protein abundance in saliva varies considerably from person to person, influenced by genetics, diet, oral health, circadian rhythms, and glandular physiology. Any biomarker that survives the transition from discovery to clinical use must demonstrate that the differences between infected and uninfected individuals exceed this background variation, ideally in independent and larger cohorts.

Even with those caveats, the study expands the current understanding of salivary protein profiles associated with HBV and HCV infections and supports the broader proposition that saliva can serve as a noninvasive source of biomarkers for viral hepatitis. As nanotechnology-based detection methods continue to improve sensitivity for low-abundance analytes, candidate proteins such as IgG Fc-binding protein, haptoglobin, prolactin-inducible protein, submandibular gland androgen-regulated protein 3, and complement C3 provide concrete molecular targets for follow-up studies using targeted mass spectrometry or immunoassays. For a disease burden measured in hundreds of millions of chronic infections globally, a simple spit test that could flag liver disease earlier, or track its course without a needle, remains a compelling goal, and this proteomic survey marks a measured but meaningful step along that path.

Subject of Research: Salivary protein biomarker discovery for hepatitis B and C virus infection using label-free mass spectrometry

Article Title: An inter-individual variation study reveals new candidate biomarkers for hepatitis B and C

Article References: Campanhon, I. B., Gonçalves, L. D. R., Sandim, V., Nunes, R. D. O., Melo, A. C. D. A., Moreira, M. F., & Soares, M. R. (2026). An inter-individual variation study reveals new candidate biomarkers for hepatitis B and C. BMC Infectious Diseases. https://doi.org/10.1186/s12879-026-14449-2

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14449-2

Keywords: hepatitis B, hepatitis C, HBV, HCV, saliva, biomarkers, proteomics, mass spectrometry, label-free quantification, liver disease, viral hepatitis, diagnostics

The anatomical logic behind this connection is elegant. The liver receives the entire venous outflow of the gut through the portal circulation, meaning it is continuously bathed in microbial products, metabolites and dietary antigens. In return, the liver secretes bile acids and other bioactive mediators into the intestine that directly shape which microbial species can thrive there. This bidirectional communication network, known as the gut–liver axis, places the immune system at its centre, tasked with maintaining a delicate equilibrium between tolerance toward commensal bacteria and robust defence against pathogens. T cells are uniquely positioned within this axis because they can recognize an extraordinarily broad spectrum of microbial antigens, and their differentiation, function and plasticity are in turn profoundly sculpted by microbial cues.

The review details how specific gut microbes direct the fate of distinct T helper subsets with remarkable precision. Segmented filamentous bacteria, for example, are a classical inducer of Th17 cells: their adhesion to intestinal epithelial cells triggers secretion of serum amyloid A, which acts on CD11c-positive cells to potentiate Th17 differentiation, amplified by a positive feedback loop involving interleukin-1β. More recently, the ubiquitous commensal Alcaligenes faecalis was shown to induce intestinal Th17 cells through the Trim21–Fbxw7 axis, and even the fungus Candida albicans can promote Th17 accumulation in the colon. Bacterial metabolites add a second layer of control. Short-chain fatty acids such as acetate, propionate and butyrate, secondary bile acids including deoxycholic acid and isolithocholic acid, and tryptophan-derived indoles all modulate Th17, Th1 and regulatory T cell programmes, often through inhibition of histone deacetylases or direct engagement of transcription factors such as RORγt.

Regulatory T cells, which express the transcription factor FOXP3 and enforce immune tolerance, are equally dependent on microbial instruction. Genera including Clostridium, Bacteroides, Bifidobacterium and Helicobacter promote colonic Treg induction, while Akkermansia muciniphila alleviates colonic inflammation by expanding RORγt-positive Treg responses. Butyrate and propionate enhance Foxp3 expression through histone acetylation at conserved non-coding sequences, and specific bile acid metabolites such as 3β-hydroxydeoxycholic acid promote Treg generation. Beyond conventional T cells, the review highlights innate-like lymphocytes with deep microbial entanglement: mucosal-associated invariant T cells depend on early-life exposure to riboflavin-synthesizing commensals, which produce the potent antigen 5-OP-RU, while hepatic natural killer T cells are regulated by microbiota-driven bile acid metabolism that controls CXCL16 expression in liver sinusoidal endothelial cells. Gamma-delta T cells, abundant in both liver and intestine, respond to microbial lipid antigens presented by hepatocytes and modulate their interleukin-17 output according to bacterial load.

Crucially, the communication is not one-way. T cells themselves reshape the microbial ecosystem. Microbiota-derived extracellular ATP constrains T follicular helper cell function through the P2X7 receptor, limiting secretory IgA production; in P2X7-deficient mice, excessive IgA disrupts microbial composition and drives metabolic dysregulation. Gamma-delta T cell-deficient mice display altered microbiota composition that feeds back into immune dysregulation, and studies of NKT cell-deficient animals have reported shifts in commensal communities, although recent work using littermate controls suggests maternal transmission and caging conditions may matter more than genotype. T cell plasticity further complicates the picture: Th17 cells can convert toward Th1 or T follicular helper phenotypes, and while the initial conversion of CD8-positive to CD4-positive T cells can occur without microbes, their subsequent homing and expansion in the gut critically depend on microbial signals.

When this finely balanced system fails, the consequences for the liver can be severe. The review describes how disruption of the intestinal barrier, the so-called leaky gut, permits bacteria, toxins and microbial antigens to translocate into the portal vein and systemic circulation. Molecular mimicry provides one mechanistic bridge: the pyruvate dehydrogenase complex E2 of Escherichia coli cross-reacts with its human counterpart at the T cell receptor level, contributing to primary biliary cholangitis, while cross-reactivity between microbial antigens and host components has been implicated in primary sclerosing cholangitis and autoimmune hepatitis. Gut dysbiosis, characterized by reduced microbial diversity, overgrowth of pathogenic taxa and depletion of beneficial commensals, accompanies virtually every form of chronic liver disease, and advanced cirrhosis additionally enriches virulence factors and antimicrobial resistance genes within the microbiome.

Disease-specific examples illustrate the diversity of these pathogenic axes. In autoimmune hepatitis, the pathobiont Enterococcus gallinarum translocates to the liver, where its DNA has been detected in patients and where it drives Th17 responses and autoantibody production in mice; conversely, the microbial metabolite indole-3-carboxaldehyde ameliorates immune-mediated hepatitis by activating the aryl hydrocarbon receptor in T cells. In primary sclerosing cholangitis, Klebsiella pneumoniae with strain-specific epithelial pore-forming capacity breaches the intestinal barrier and provokes robust hepatic Th17 responses, while translocated Lactobacillus gasseri induces IL-17A production by gamma-delta T cells in cholestatic models. In alcohol-associated liver disease, ethanol promotes fungal dysbiosis and generates Candida albicans-specific Th17 cells that migrate to the liver and exacerbate injury through IL-17 signalling on Kupffer cells, while peripheral MAIT cells become depleted and hyperactivated through heightened exposure to translocated bacterial products.

Metabolic dysfunction-associated steatotic liver disease, which affects approximately 38 percent of the global adult population, adds yet another dimension. High-fat diet models show depletion of protective intestinal Th17 cells, promoting microbial migration that accelerates disease, while microbiota-derived lipid antigens presented by hepatocytes via CD1d stimulate hepatic IL-17-producing gamma-delta T cells. Faecal bacterial extracts from patients with MASLD-related hepatocellular carcinoma induce immunosuppressive phenotypes ex vivo, expanding Treg cells and attenuating CD8-positive T cell function in a short-chain fatty acid-dependent manner. In chronic hepatitis B, bacterial extracts from non-cirrhotic patients promote Th17 expansion whereas those from cirrhotic patients inhibit Th1 cells, and strikingly, a probiotic consortium of Bifidobacterium longum, Enterococcus faecalis and Lactobacillus acidophilus, together with its metabolite spermidine, suppresses HBV replication by augmenting IFNγ-positive CD4-positive T cell immunity.

These mechanistic insights are now feeding into a therapeutic pipeline that targets both sides of the axis. Microbiota-directed interventions include probiotics such as Lactobacillus acidophilus, which attenuated cholestatic liver damage in mice and improved liver function in cholestatic patients, and Lactobacillus rhamnosus GG, which alleviated liver injury in moderate alcohol-associated hepatitis. Prebiotics such as inulin and camu-camu have shown benefits in metabolic liver disease, although inulin failed to improve early alcoholic liver injury despite reshaping the microbiome. Faecal microbiota transplantation increased bacterial diversity and reduced alkaline phosphatase in primary sclerosing cholangitis and restored intestinal permeability in MASLD, though it did not improve hepatic fat fraction or insulin resistance. On the T cell side, chimeric antigen receptor T cell therapy eliminated pathogenic PD-1-positive CD8-positive T cells that drive hepatocyte pyroptosis in autoimmune liver disease models, autologous Treg infusion significantly reduced liver enzymes in a patient with refractory PSC/UC, and low-dose interleukin-2 therapy that selectively expands Tregs has shown early promise.

The authors caution that the gut–liver–immune network is dynamic and bidirectional, meaning that targeting a single component may trigger unanticipated cascades; indeed, the efficacy of CAR-T therapy itself can be modulated by the intestinal microbiota. They argue that future progress will require patient-stratified approaches, deeper elucidation of the specific microbial taxa and immunological mechanisms underlying each disease, and clinical validation of candidate targets. If that integration of microbiome science with translational immunology succeeds, the microbial cues that currently fuel chronic liver disease could be repurposed as precise levers for its prevention and treatment, opening a genuinely new therapeutic frontier for conditions that have long defied conventional intervention.

Subject of Research: Bidirectional interactions between gut microbiota and T cell immunity in the progression of chronic liver disease

Article Title: Microbial cues and T cell immunity: deciphering their interactions in chronic liver disease

Article References: Liu, Y., Yu, B., Liu, Q., Ma, X., & Tang, R. (2026). Microbial cues and T cell immunity: deciphering their interactions in chronic liver disease. Experimental & Molecular Medicine. https://doi.org/10.1038/s12276-026-01831-y

Image Credits: AI Generated

DOI: 10.1038/s12276-026-01831-y

Keywords: gut-liver axis, gut microbiota, T cells, chronic liver disease, Th17 cells, regulatory T cells, autoimmune liver disease, alcohol-associated liver disease, MASLD, viral hepatitis, microbial metabolites, immunotherapy

The study drew on a large community screening cohort in Guangzhou involving 30,012 individuals who underwent serological testing for viral hepatitis markers, including hepatitis B surface antigen and hepatitis C virus antibodies. From this effort, 1,676 people tested positive for viral hepatitis. After excluding 516 participants with incomplete baseline questionnaires, the final analytical sample comprised 1,160 individuals. The researchers then divided these screening-positive patients into two groups based on a single, clinically meaningful behavior: whether they returned to certified viral hepatitis treatment facilities to receive standardized follow-up after learning of their positive result. Those who did, 285 cases or 24.57 percent of the sample, formed the observation group, while the 875 cases who did not return, 75.43 percent, formed the control group. The stark imbalance between the two groups is itself a finding worth pausing on, because it quantifies the scale of the linkage problem that hepatitis programs face even in a well-resourced urban setting with accessible treatment facilities.

To measure knowledge, all participants completed a self-developed six-item standardized questionnaire covering prevention and treatment of viral hepatitis. A total score of at least three points, meaning more than half of the six-item scale, was defined as adequate hepatitis knowledge. The team then applied a battery of statistical techniques to probe the relationship between knowledge and adherence: subgroup comparisons, stratified chi-squared analysis, multivariate linear regression, binary logistic regression with interaction terms, and one-to-three propensity score matching to adjust for baseline differences between the groups. This methodological arsenal matters because simple comparisons between people who seek care and those who do not are notoriously vulnerable to confounding. Patients who return for follow-up may differ systematically in age, education, disease awareness, or family experience with liver disease, and any of those differences could masquerade as a knowledge effect if not properly controlled.

The headline result was negative, and the authors are explicit about it. Across all screening-positive patients, no significant overall correlation was observed between hepatitis knowledge level and follow-up adherence. The knowledge qualification rate was 53.33 percent in the observation group versus 52.11 percent in the control group, a difference that was statistically indistinguishable with a P value of 0.720. In other words, roughly half of the patients in both groups possessed adequate knowledge about hepatitis prevention and treatment, and knowing more did not predict who would come back for care. This null finding challenges a widespread assumption in public health practice, namely that health education campaigns which raise awareness will translate into improved health-seeking behavior. The Health Belief Model, which underpins much of health behavior theory, posits that perceived susceptibility and severity drive action, but this study suggests that knowledge alone, without the motivational scaffolding of personal or family experience, may be insufficient to move patients from awareness to action.

When the researchers examined demographic and clinical characteristics, most variables showed no significant differences between the adherent and non-adherent groups. Gender, ethnicity, marital status, education, occupation, and hepatitis type all failed to distinguish the two groups in significance testing. Two variables did stand out: age, with a P value of 0.016, and family history of liver disease, with a P value below 0.001. Propensity score assessment using standardized mean differences demonstrated adequate balance for age after matching, at 0.022, but family history showed severe baseline imbalance, with a standardized mean difference of 0.718. This imbalance is a critical technical detail, because it means that patients with a known family history of liver disease were dramatically overrepresented among those who returned for follow-up, and any analysis that fails to account for this difference risks drawing distorted conclusions about what drives adherence.

The stratified analysis revealed the study’s most striking pattern. Among participants with a definite family history of liver disease, the knowledge qualification rate in the observation group was significantly higher than in the control group, suggesting that for these patients, knowledge and adherence traveled together. Among participants with unknown family history, the pattern reversed dramatically: only 6.58 percent of the adherent observation group had adequate knowledge, compared with 41.45 percent of the non-adherent control group. This reversed gap is one of the most intriguing findings in the paper, hinting that patients without a known family history who nonetheless adhere to follow-up may be doing so for reasons unrelated to knowledge, while those with unknown family history who possess knowledge may still fail to act on it. Subgroup analyses restricted to the observation group further showed that family history, with a P value of 0.001, and educational attainment, with a P value of 0.016, were both associated with hepatitis knowledge qualification status, with participants who had a confirmed family history of liver disease and college-level or higher education exhibiting the highest qualification rates.

Yet the formal statistical test for moderation complicates the story. In multivariate logistic regression analysis, the interaction term between family history and total knowledge score lacked statistical significance, with an odds ratio of 0.953 and a P value of 0.729. This means that, strictly speaking, the global analysis does not support family history as a formal statistical moderator of the knowledge-adherence relationship. However, stratified analyses revealed divergent associations within subgroups: the positive association between knowledge score and follow-up compliance was detected only among patients with a definite family history of liver disease, with an odds ratio of 1.118 and a P value of 0.015. For every one-point increase in knowledge score, the odds of follow-up compliance rose by roughly 12 percent in this subgroup, while no such relationship existed in the rest of the population. The authors are careful to frame this as subgroup heterogeneity rather than confirmed moderation, and they explicitly call for further multi-center longitudinal studies and randomized controlled trials to validate the subgroup findings and evaluate stratified intervention effects.

The practical implications reach well beyond Guangzhou. The authors conclude that universal health education alone cannot improve follow-up compliance, a conclusion that should give pause to program designers who rely on broadcast-style awareness campaigns to close the screening-to-treatment cascade. Instead, they advocate targeted strategies, including risk-stratified health education based on family history and integrated screening-treatment linkage with case management, as the appropriate tools for grassroots hepatitis prevention. This aligns with a broader shift in global hepatitis elimination strategy, championed by the World Health Organization, toward simplification and decentralization of care, in which every person who screens positive is actively accompanied into evaluation and treatment rather than simply handed information and left to navigate the system alone. Case management, in which a designated worker tracks and supports each positive patient, directly addresses the 75 percent attrition observed in this cohort.

Several limitations deserve attention when weighing these findings. The cross-sectional design captures a single moment in time and cannot establish whether low knowledge causes poor adherence or whether both reflect deeper structural barriers such as cost, distance, work obligations, or stigma. The knowledge instrument was self-developed rather than a validated external scale, and the severe baseline imbalance in family history, despite propensity score matching, means residual confounding cannot be excluded. The observation group was also relatively small at 285 participants, which limits statistical power for interaction testing, and interaction analyses are notoriously underpowered in general. Still, the study’s scale, with more than 30,000 community members screened and over 1,100 positive patients analyzed, and its rigorous multi-method statistical approach make it a valuable contribution. As countries pursue the 2030 elimination targets for viral hepatitis, the message from Guangzhou is clear: information is necessary but not sufficient, and the patients who most need to act on what they know may be precisely those for whom knowledge carries no personal urgency until programs make follow-up effortless, personal, and connected to their own family story of liver disease.

Subject of Research: The relationship between hepatitis knowledge, family history, education, and follow-up adherence among community screening-positive viral hepatitis patients in Guangzhou, China

Article Title: Family history and education moderate adherence and knowledge in viral hepatitis patients: a cross-sectional study in Guangzhou, China

Article References: Huang, Z., Li, B., Lu, A., Tan, Y., Lin, L., Liu, S., Lin, G., Ning, Q., Liu, J., Liang, H., Du, Z., Li, J., Guan, Y., & Tang, X. (2026). Family history and education moderate adherence and knowledge in viral hepatitis patients: a cross-sectional study in Guangzhou, China. Virology Journal. https://doi.org/10.1186/s12985-026-03273-4

Image Credits: AI Generated

DOI: 10.1186/s12985-026-03273-4

Keywords: viral hepatitis, hepatitis B, hepatitis C, follow-up adherence, health knowledge, family history, health education, screening-treatment linkage, cross-sectional study, Guangzhou, hepatocellular carcinoma, cirrhosis

The technical approach matters as much as the headline numbers. Rather than relying on self-reported diagnoses, which are notoriously unreliable in stigmatized populations, the researchers screened every sample with rapid diagnostic tests for hepatitis B surface antigen, the protein marker of active HBV infection, and for hepatitis C antibodies, which indicate past or present HCV exposure. Every positive result then underwent confirmatory viral load testing to distinguish active, replicating infection from resolved or false-positive serology. This two-stage design is essential because surface antigen positivity and detectable DNA carry very different clinical implications, from chronic infection requiring tenofovir-based therapy to the long-term risk of hepatocellular carcinoma.

The results paint a picture of moderate but non-trivial transmission. Hepatitis B surface antigen was detected in 25 of 729 participants, a crude prevalence of 3.4 percent that fell to 2.7 percent after adjustment for the respondent-driven sampling design, with a 95 percent confidence interval of 1.2 to 4.2 percent. Among those 25 surface-antigen-positive individuals, 92 percent had detectable HBV DNA, confirming active viral replication, with a median viral load of 3.0 log10 IU per milliliter. Hepatitis C antibody was found in 12 participants, or 1.6 percent crude prevalence, rising slightly to 1.7 percent when adjusted, and only a third of those antibody-positive samples, four of twelve, carried detectable HCV RNA.

That distinction between antibody positivity and detectable RNA is epidemiologically revealing. In settings where HCV transmission is driven primarily by injection drug use, most antibody-positive individuals remain viremic because the infection persists without treatment. The finding that two-thirds of antibody-positive participants in Kigali had no detectable RNA suggests a mixture of resolved infections and possibly past exposure through non-injection routes, though the small number of positive samples demands caution in interpretation. Still, the pattern hints that sexual transmission or other exposure pathways may contribute alongside any injection-related risk in this population.

To identify who was most at risk, the team used approximate Bayesian logistic regression with penalized likelihood estimation via data augmentation, a modeling strategy suited to sparse events and complex sampling designs. For hepatitis B, three factors emerged as independently associated with surface antigen positivity. Each additional year of age raised the odds by 4 percent, with an adjusted odds ratio of 1.04 and profile-likelihood limits of 1.00 to 1.09. Having sexual partners who had ever injected drugs more than tripled the odds, at an adjusted odds ratio of 3.13 with limits of 1.51 to 6.53. And reporting symptoms of a sexually transmitted infection in the year before enrollment roughly doubled the odds, at 2.11 with limits of 1.03 to 4.34. For hepatitis C, age was the only significant factor, with an adjusted odds ratio of 1.06 per year.

The age gradient deserves particular attention. When the authors stratified their data, prevalence among participants aged 35 and older reached 7.6 percent for hepatitis B surface antigen and 3.8 percent for hepatitis C antibodies, roughly two to three times the overall estimates. This older subgroup is one in which the same research team had previously documented higher burdens of HIV and other sexually transmitted infections, suggesting a convergence of infectious disease risks that accumulates over a lifetime of exposure. In practical terms, the men and transgender women most likely to harbor silent hepatitis infection are also those most likely to be engaged in HIV care, creating a natural opportunity for integrated screening.

The strong association between hepatitis B and partners who inject drugs carries perhaps the most programmatic weight. It implies that the sexual networks of MSM and transgender women who do not inject drugs overlap substantially with networks of people who do, allowing the virus to bridge between transmission routes that public health programs often address separately. Rwanda’s hepatitis programming, like much of the global response, has historically treated sexual and parenteral transmission as distinct problems requiring distinct services. The Kigali data argue that for these key populations, such silos are a liability, and that interventions should simultaneously address injection-related and sex-related acquisition risks.

Clinically, the stakes of missing chronic hepatitis B are considerable. Untreated chronic HBV infection is a leading cause of cirrhosis and hepatocellular carcinoma, and the authors explicitly frame ongoing screening as a way to strengthen not only prevention and treatment programs but also liver cancer surveillance. Rwanda has administered the pentavalent DTP-HepB-Hib vaccine in its childhood immunization schedule for years, which protects younger cohorts but does nothing for adults who were born before introduction or who were infected before vaccination. Tenofovir disoproxil fumarate and tenofovir alafenamide can suppress HBV replication effectively, while direct-acting antivirals now cure more than 95 percent of chronic hepatitis C cases, measured as sustained virological response at twelve weeks. None of these tools reach people who are never tested.

The study’s methodology also illustrates both the power and the limits of respondent-driven sampling. By having participants recruit peers from their own networks, RDS reaches populations that conventional sampling cannot, and the RDS adjustment attempts to correct for the non-random structure of those recruitment chains. But the approach cannot eliminate all bias, and the authors report sensitivity analyses examining how their Bayesian models performed under different assumptions about prior odds ratios. A further constraint is poignant: because contact information was not retained after the parent study concluded, the hepatitis test results could not be returned to the participants themselves, a limitation the ethics review at Emory University and the Rwanda National Research Ethics Committee weighed when approving the use of stored samples.

What emerges from Kigali is a call to action grounded in numbers rather than alarm. Hepatitis B and C are not exploding in this population, but they are present, active, and concentrated in identifiable subgroups: older MSM and transgender women, people reporting recent STI symptoms, and those connected to injection drug use networks. Rwanda’s experience with HIV, where key-population-focused services helped drive down incidence, offers a template. Embedding rapid hepatitis screening into existing HIV and STI services, extending vaccination and treatment to adults at risk, and designing outreach that acknowledges the overlap between sexual and injection networks would translate this study’s findings into measurable public health gain. As the authors conclude, tailored interventions for older MSM and transgender women are needed now, before silent infections convert into cirrhosis and cancer that screening could have prevented.

Subject of Research: Prevalence and risk factors of hepatitis B and C infection among men who have sex with men and transgender women in Kigali, Rwanda

Article Title: The prevalence of and factors associated with hepatitis B and hepatitis C among men who have sex with men in Kigali, Rwanda

Article References: Twahirwa Rwema, J. O., Niyongira, E., Okonkwo, N. E., Bizimana, J., Makuza, J. D., Hamill, M. M., Lyons, C. E., Nyombayire, J., Rwibasira, G. N., Sullivan, P., Allen, S., Karita, E., & Baral, S. D. (2026). The prevalence of and factors associated with hepatitis B and hepatitis C among men who have sex with men in Kigali, Rwanda. BMC Infectious Diseases. https://doi.org/10.1186/s12879-026-14498-7

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14498-7

Keywords: hepatitis B, hepatitis C, men who have sex with men, transgender women, Rwanda, Kigali, viral hepatitis, respondent-driven sampling, HBsAg, viral load, injection drug use, public health

The scale of the region’s burden makes these findings consequential far beyond the Western Pacific. According to the WHO’s 2026 Global Hepatitis Report, roughly 240 million people were living with chronic HBV infection worldwide in 2024, and the virus caused about 1.1 million deaths from cirrhosis and liver cancer — a 17 percent increase in HBV-related mortality since 2015. The Western Pacific alone accounted for an estimated 102 million people living with hepatitis B in 2024, and several countries that contribute disproportionately to the global toll, including China, the Philippines, Viet Nam and Indonesia, sit within the region. WHO’s elimination strategy calls for a 90 percent reduction in new infections and a 65 percent reduction in hepatitis-related deaths by 2030, compared with 2015 baselines.

Between 2015 and 2024, the modelled estimates show genuine progress on the transmission side of the ledger. Total HBV prevalence in the region fell from 5.28 percent to 4.58 percent, corresponding to a drop from about 100.8 million to 89.7 million people living with the virus. Chronic HBV incidence fell from 6.32 to 3.16 new infections per 100,000 population, and prevalence among children under five declined from 0.40 percent to 0.28 percent — although that childhood figure has plateaued since 2019, well above the WHO 2030 target of 0.1 percent. Mortality moved in the opposite direction: the HBV-related death rate rose from 22.88 to 24.70 per 100,000, with estimated annual deaths climbing from 436,363 to 484,055.

The researchers quantified country-specific trends using estimated annual percentage changes, derived from log-linear regression of modelled annual rates against calendar year. Chronic incidence was classified as declining in 22 of the 34 countries and areas, with the steepest falls in Japan (an EAPC of −19.24 percent per year) and the Republic of Korea (−15.66 percent). Mortality, by contrast, was classified as increasing in 31 of 34 countries and areas, spanning every analytical subregion the team examined: East Asia, Southeast Asia, Australasia and the Pacific Island Countries and Territories. Japan (−3.09 percent per year) and New Zealand (−1.37 percent) were the only exceptions. The Marshall Islands recorded the sharpest mortality increase at 6.44 percent per year, followed by Tonga and Cambodia at 3.97 percent each.

Underlying the regional averages is striking heterogeneity. Among children under five, prevalence in 2024 had fallen to 0.08 percent in China, 0.03 percent in the Republic of Korea, 0.01 percent in Japan, 0.06 percent in Australia and 0.02 percent in New Zealand — all meeting the 2030 elimination target of 0.1 percent or lower. Yet in Papua New Guinea, under-five prevalence rose 24.61 percent over the decade to reach 2.38 percent, and increases were also recorded in New Caledonia, Samoa and Vanuatu. Ten other Pacific countries and territories still had childhood prevalence above 1 percent in 2024. Total prevalence rose only in the Marshall Islands (+22.73 percent) and Tuvalu (+1.49 percent), but the range across the region was enormous, from 0.73 percent in Japan to 9.16 percent in Tonga.

The statistical relationship between incidence and mortality trends was, notably, only modest. Country-level estimated annual percentage changes for chronic incidence and mortality were positively correlated (Pearson r = 0.39), and incidence trends explained just 15.2 percent of the between-country variation in mortality trends. That weak coupling reinforces the study’s central methodological message: the two indicators measure temporally distinct dimensions of elimination. Chronic HBV infection progresses over decades to decompensated cirrhosis and hepatocellular carcinoma — which accounts for roughly 80 percent of primary liver cancers globally — so today’s deaths largely reflect infections acquired long before recent vaccination gains. The authors caution that their ecological design cannot determine whether rising mortality reflects population ageing, the accumulated legacy of longstanding infection, gaps in diagnosis and treatment, or changes in how deaths are recorded.

Vaccination coverage, the backbone of HBV prevention, remained comparatively high regionally but varied dramatically between countries. Three-dose infant vaccination coverage stayed above 90 percent across most of the study period, but birth-dose coverage — the most critical intervention for preventing mother-to-child transmission — hovered around 80 percent, short of the 2030 target of 90 percent or more. In 2024, birth-dose coverage ranged from 99.65 percent in Tuvalu down to 26.20 percent in Papua New Guinea, where three-dose coverage had also fallen to 39.84 percent. Fiji’s birth-dose coverage collapsed from 99 percent in 2020 to 39.12 percent in 2024, and declines in three-dose coverage were seen in the Cook Islands and Samoa. Japan and New Zealand, which run targeted rather than universal birth-dose programmes, register low nominal birth-dose coverage for that reason rather than programme failure.

Exploratory analyses found no robust statistical association between national vaccination coverage levels, or changes in coverage, and changes in childhood infection or chronic incidence after adjustment for multiple comparisons — a result the authors stress does not challenge established vaccine effectiveness, but instead highlights the limits of contemporary coverage figures as proxies for cumulative prevention performance. Progress towards WHO milestones was similarly uneven: by 2024, only Australia (3.70 deaths per 100,000) had reached the 2030 mortality target of 4 per 100,000, with Japan and French Polynesia the only others below the 2025 interim threshold of 7 per 100,000. Neither the study’s subregional grouping nor an alternative World Bank income classification explained much of the observed heterogeneity, pointing instead to country-specific programme gaps such as those documented in Papua New Guinea, where out-of-facility births, cold-chain constraints and vaccine availability impede timely birth-dose delivery.

The implications are stark for elimination strategy. In China, despite dramatic reductions in childhood infection, an estimated 75 million people remain chronically infected with substantial diagnosis and treatment gaps, and infection is increasingly concentrated in older cohorts. As vaccination programmes mature, the authors argue, near-term reductions in cirrhosis and liver cancer will depend less on preventing new infections and more on clinical management of people already living with the virus — expanding testing, linking patients to care, widening access to antiviral therapy, and surveillance for liver cancer, in line with WHO’s 2024 treatment guidelines. Elimination monitoring, they conclude, should treat transmission, care-cascade performance and mortality as complementary but distinct outcomes, supported by better age-specific mortality data and simplified diagnostics such as point-of-care HBV DNA testing in settings with limited laboratory capacity.

The study also carries important caveats for interpretation. Its estimates derive from a single dynamic modelling framework rather than independent surveillance, uncertainty intervals were unavailable for incidence, mortality and liver-outcome measures, and some Pacific island settings share identical model-derived trajectories because regional comparators were used where local data were sparse. Residual autocorrelation was evident in many mortality models, meaning conventional confidence intervals may appear more precise than the underlying data warrant. The authors did include sensitivity analyses addressing influential observations, shared trajectories, departures from log-linearity and alternative country classifications, and the core finding — diverging incidence and mortality trajectories — held throughout. Even with those caveats, the message for the region that bears nearly half the world’s hepatitis B burden is difficult to escape: falling infection counts alone will not deliver elimination by 2030 without a parallel, and urgently scaled, assault on the disease burden carried by tens of millions already infected.

Subject of Research: Trends and disparities in hepatitis B virus burden and progress toward WHO elimination targets across the Western Pacific Region from 2015 to 2024.

Article Title: Trends and disparities in hepatitis B burden in the Western Pacific Region, 2015–2024: a subregional analysis using modelled data

Article References: Maung, H. T., Ghrabi, M. A., Morishita, F., Hubraj Yadav, R. P., Giang Tran, H. T., & Izumi, K. (2026). Trends and disparities in hepatitis B burden in the Western Pacific Region, 2015–2024: a subregional analysis using modelled data. The Lancet Regional Health – Western Pacific, 75, Article 101991. https://doi.org/10.1016/j.lanwpc.2026.101991

Image Credits: AI Generated

DOI: 10.1016/j.lanwpc.2026.101991

Keywords: hepatitis B, Western Pacific Region, viral hepatitis, HBV mortality, vaccination, birth dose, epidemiology, elimination targets, cirrhosis, hepatocellular carcinoma, Polaris Observatory, public health

The study, published in BMC Infectious Diseases, analyzed 4,668 hepatitis E cases drawn from China’s National Notifiable Disease Reporting System, a nationwide passive surveillance network to which clinicians and laboratories must report diagnoses of legally designated infectious diseases. Over the six-year window, Shanghai recorded an average annual notification rate of 3.14 cases per 100,000 population. That figure places hepatitis E firmly on the map of locally relevant infectious diseases in the city, even though it rarely attracts the public attention devoted to respiratory pathogens or foodborne outbreaks. Hepatitis E virus, or HEV, is transmitted primarily through the fecal-oral route, most often via contaminated water, and through zoonotic pathways, particularly the consumption of undercooked pork, game meat, and shellfish from infected animals.

To understand the disease’s rhythm in time, the researchers applied temporal scan statistics, a method that slides a window of variable length across the surveillance timeline and asks whether case counts within any given interval exceed what would be expected by chance. The analysis identified a statistically significant temporal cluster spanning January 1, 2017 to May 31, 2019, with a relative risk of 1.35 and a log likelihood ratio of 52.18, well beyond the threshold of statistical significance. In practical terms, cases accumulated during this early window at a rate roughly a third higher than the six-year baseline. The team also detected a recurring seasonal signature: notifications clustered in the months from December through May, a winter-to-spring peak that echoes patterns reported in other regions of China and is often linked to seasonal dietary customs, including festival-period consumption of raw or undercooked animal products.

The spatial dimension of the analysis proved more surprising. When the researchers ran a spatial-temporal scan across the entire six-year period, they found one statistically significant cluster with a relative risk of 1.73 and a log likelihood ratio of 135.74. Communities with the highest raw notification rates tended to sit in the southeastern parts of the city, but the most likely cluster identified by the scan statistic was not there. Instead, it was located in the urban core. When the team repeated the scan year by year, the same pattern held: the most likely cluster consistently fell in central urban districts, with secondary clusters appearing in suburban towns on the metropolitan periphery. The discrepancy between where cases are most numerous and where the statistical signal of clustering is strongest is itself informative, because scan statistics adjust for underlying population size and expected case counts rather than simply flagging the tallest bars on a map.

That adjustment matters. Dense urban neighborhoods generate large numbers of cases in absolute terms simply because so many people live there, but a cluster statistic asks a subtler question: are there more cases than the local population structure would predict? The fact that the urban core repeatedly emerged as the most likely cluster suggests that something about these districts, beyond sheer headcount, elevates hepatitis E transmission or detection. Possibilities include greater reliance on food purchased from restaurants and markets, more frequent consumption of seafood and pork dishes, higher turnover of food handlers, or simply better access to healthcare and laboratory testing, which would raise the probability that infections are recognized and reported. The study’s design cannot distinguish among these mechanisms, a limitation the authors acknowledge explicitly.

To probe what distinguishes clustered communities from the rest, the researchers turned to binary logistic regression, a statistical technique that estimates the odds of membership in a high-risk cluster as a function of community-level characteristics. Three variables emerged as significant. Population density showed the strongest association: communities with higher density had markedly higher odds of falling into a high-risk cluster, with an odds ratio of 7.367. The count of shopping malls, used as a proxy for commercial activity and food-service intensity, was also positively associated, with an odds ratio of 1.531. Intriguingly, distance to the nearest river showed a negative association, with an odds ratio of 0.742, meaning that communities closer to rivers had higher odds of clustering. This last finding is consistent with the hypothesis that waterways and the aquatic food chains they support, including shellfish and fish harvested or sold in riverside markets, may play a role in HEV transmission, although the ecological nature of the analysis means the link remains speculative.

The authors are careful, and rightly so, about how far these associations can be pushed. Because the analysis operates at the level of communities rather than individuals, it is vulnerable to the ecological fallacy: a community-level correlation does not establish that the people within a cluster acquired their infections through the hypothesized route. A mall-dense neighborhood may have many cases not because its residents eat at malls but because mall density tracks with other unmeasured features of urban life. Similarly, proximity to a river may correlate with historical settlement patterns, sanitation infrastructure, or dietary traditions rather than with any direct waterborne exposure. The researchers describe their findings as ecological and hypothesis-generating, and they emphasize that confirming the actual transmission routes of hepatitis E in Shanghai will require individual-level epidemiological studies, including case-control designs that compare exposures of confirmed cases with those of matched controls.

Even with those caveats, the study carries practical weight for public health planning. Shanghai sits within the Yangtze River Delta, one of the most economically dynamic and densely interconnected regions in the world, and its surveillance system feeds into national and global assessments of viral hepatitis burden. The World Health Assembly has set targets for eliminating viral hepatitis as a public health threat, and hepatitis E, though often self-limiting in healthy adults, can be devastating for pregnant women, who face elevated risks of fulminant liver failure, and for people with chronic liver disease or compromised immune systems. Knowing that risk concentrates in dense, commercially active, riverside urban communities gives health authorities a concrete template for targeting interventions, whether that means food-safety inspections in high-risk districts, health education campaigns timed to the December-to-May seasonal peak, or enhanced testing of at-risk populations such as pregnant women in clustered neighborhoods.

The methodological approach also deserves attention from the wider infectious-disease community. Spatial-temporal scan statistics, originally developed for cancer cluster detection and later adapted for communicable disease surveillance, have become a standard tool for turning routine notification data into actionable geographic intelligence. By combining them with community-level socioeconomic and environmental covariates in a regression framework, the Shanghai team demonstrated a pipeline that other cities with robust notifiable-disease systems could replicate. The work also underscores the value of long surveillance windows: a six-year dataset made it possible to separate a one-off elevated period in 2017 through 2019 from a stable seasonal rhythm and a persistent geographic core, distinctions that shorter studies would blur.

What remains to be resolved is the biology behind the map. Genotyping of viral sequences from urban and suburban cases could reveal whether a single transmission chain or multiple introductions drive the clusters, and molecular epidemiology could test whether zoonotic strains from the pork supply chain dominate in commercial districts while water-associated genotypes predominate near rivers. Seroprevalence surveys could measure how much asymptomatic infection the notification data miss, since hepatitis E is frequently mild or silent in young, healthy adults. Until such studies are done, the Shanghai analysis stands as a carefully constructed hypothesis: that in a modern megacity, hepatitis E risk is written into the urban fabric itself, concentrated where people, commerce, and waterways converge. It is a hypothesis that public health officials in Shanghai, and in riverine megacities across Asia and beyond, now have both the reason and the roadmap to test.

Subject of Research: Spatial-temporal epidemiology and community-level risk factors of hepatitis E virus infection in Shanghai, China

Article Title: Identification of the spatial-temporal cluster and risk factors of hepatitis E from 2017 to 2022 in Shanghai, China

Article References: Zhi-Tao, M., Ling-Xiao, Q., Kai-Yun, C., Xin, S., Di, X., Zhao-He, L., Yi-Han, L., Kang, C., Jing, L., & Hong, R. (2026). Identification of the spatial-temporal cluster and risk factors of hepatitis E from 2017 to 2022 in Shanghai, China. BMC Infectious Diseases. https://doi.org/10.1186/s12879-026-14463-4

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14463-4

Keywords: hepatitis E, hepatitis E virus, spatial-temporal analysis, disease cluster, Shanghai, epidemiology, public health surveillance, risk factors, population density, zoonotic transmission, viral hepatitis, logistic regression