The observational study examined human sera collected in 2015 and 2022 from 10 municipalities in Cádiz. Samples were first screened for West Nile virus antibodies with enzyme-linked immunosorbent assays. Positive samples then underwent viral neutralization tests against West Nile virus and related orthoflaviviruses, including Usutu, dengue, tick-borne encephalitis and Zika viruses.

The investigators used the neutralization results to identify evidence of a West Nile virus-specific immune response in the tested population. West Nile virus-specific antibodies were confirmed in samples from three municipalities in 2015 and nine municipalities in 2022. The reported seroprevalence increased from 0.2% in 2015 to 0.9% in 2022.

These estimates describe the proportion of tested individuals with evidence of exposure, rather than identifying the time, place or circumstances of individual infections. In parallel, investigators trapped mosquitoes in Cádiz between 2022 and 2024 and analyzed the pools using reverse-transcription polymerase chain reaction to detect and characterize circulating orthoflaviviruses. West Nile virus-positive mosquitoes were detected in some sampled areas, including places where human and animal cases had been reported.

Two additional mosquito pools tested positive for Usutu virus, and genetic characterization placed both in the Africa-3 lineage. The authors described the Usutu finding as the first report of that virus in Cádiz, demonstrating circulation of a related mosquito-borne virus in the same regional environment. The combined findings support the authors’ conclusion that West Nile virus is endemic in Cádiz and that Usutu virus is co-circulating locally.

The human and mosquito data address different aspects of transmission: the serology indicates prior immune exposure among sampled residents, while the molecular detections document viral RNA in captured mosquitoes. The components were not sampled over identical periods, however, with human sera collected in two years and mosquitoes sampled across three years, so they do not constitute a continuous year-by-year record. The study also does not establish the precise routes, timing or frequency of human infection.

The authors propose that One Health surveillance combining mosquito monitoring, human immune-response testing and characterization of circulating viruses can help researchers understand orthoflavivirus transmission dynamics in endemic regions.

Subject of Research: Human seroprevalence and mosquito surveillance of West Nile and Usutu viruses in Cádiz, Spain

Article Title: Integrated human seroprevalence study and entomological surveillance of West Nile virus in Cádiz, Spain

Article References: Guillén-Calvo, L., Freyre-Carrillo, C., Herrero, L., Fernández-Martínez, B., Calonge, E., Pérez-Olmeda, M., Labiod, N., Molero, F., Potente, A., Ruiz-López, M. J., Sánchez-Peña, C., Figuerola, J., Rodriguez-Iglesias, M., Sánchez-Seco, M. P., & Vázquez, A. (2026). Integrated human seroprevalence study and entomological surveillance of West Nile virus in Cádiz, Spain. Parasites & Vectors. https://doi.org/10.1186/s13071-026-07696-4

Image Credits: AI Generated

DOI: 10.1186/s13071-026-07696-4

Keywords: West Nile virus, Usutu virus, Cádiz, seroprevalence, neutralizing antibodies, mosquito surveillance, RT-PCR, orthoflaviviruses, Africa-3 lineage, One Health, Integrated, human

CMV, a member of the genus Cucumovirus in the family Bromoviridae, is regarded as one of the most destructive viruses of chilli worldwide. It infects more than 1,000 plant species, including vegetables, ornamentals, pulses, and weeds, and is transmitted primarily by aphids in a non-persistent manner. The virus survives in alternate hosts and weed reservoirs, which facilitates rapid dissemination under field conditions, and seed transmission has been reported in several hosts, contributing to long-distance spread. Recent research has further shown that CMV infection can alter host volatile emissions and plant physiology in ways that enhance aphid-mediated transmission, adding to the virus’s epidemiological fitness.

The CMV genome consists of three positive-sense single-stranded RNA molecules, designated RNA1, RNA2, and RNA3, which encode proteins involved in replication, movement, pathogenicity, and suppression of host defense responses. Based on serological properties, nucleotide divergence, and phylogenetic relationships, CMV isolates are classified into subgroup I and subgroup II, with subgroup I further divided into IA and IB lineages. Previous Indian studies have shown that most CMV isolates infecting chilli and other crop hosts predominantly belong to subgroup IA, but the majority of these investigations were confined to southern, western, or central India. Molecular epidemiological information from eastern India, particularly Bihar, remained very limited before this study.

To address this gap, researchers led by Mahesh Kumar of Dr. Kalam Agricultural College, Bihar Agricultural University, Sabour, conducted extensive field surveys during 2019 and 2020 in the major chilli-growing districts of Kishanganj, Purnia, and Bhagalpur. The surveys revealed characteristic viral symptoms including mosaic, mottling, chlorosis, leaf deformation, vein clearing, shoestring leaves, and stunted growth. A total of 355 symptomatic samples were collected: 165 from Kishanganj district at locations including Kharkhari, Motihara, Ganiyabari, Lodhabari, and Arrabari; 70 from Purnia district at Kasba, Jalalgarh, and Dagarua; and 95 from the vegetable-growing belt of Bhagalpur district, particularly Sabour and Kahalgoan near the Ganga River.

Field diagnosis based solely on symptoms proved difficult because CMV symptoms frequently overlap with those induced by other chilli-infecting viruses such as Chilli veinal mottle virus and Capsicum chlorosis virus. Chilli leaf curl virus, which induces typical upward leaf curling, puckering, and reduced leaf lamina, could be visually differentiated and was excluded from the CMV-oriented investigation. All collected samples were screened using Direct Antigen Coating Enzyme-Linked Immunosorbent Assay (DAC-ELISA), a serological method in which clarified leaf sap is adsorbed onto polystyrene microplate wells and probed with CMV polyclonal antiserum followed by an enzyme-conjugated secondary antibody, with absorbance recorded at 405 nm. The assay confirmed CMV infection in 115 of the 355 samples: 64 out of 165 from Kishanganj, 32 out of 70 from Purnia, and 19 out of 95 from Bhagalpur. The highest optical density value, 0.421, was recorded for an isolate from Jalalgarh in Purnia district that exhibited pronounced shoestring leaf symptoms, a frequent association that validates leaf narrowing and filiform symptoms as characteristic indicators of CMV infection in chilli.

Six representative isolates, four from Zone II (Belwa, Kharkhari, Purnia, and Kasba) and two from Zone IIIB (Sabour and Kahalgoan), were selected for molecular characterization based on confirmed CMV positivity, geographic representation, confirmed sap transmission, variation in symptom expression, and availability of high-quality RNA. The isolates were biologically maintained through mechanical sap inoculation on indicator hosts. Inoculated Chenopodium plants developed mild mosaic symptoms from the sixth day after inoculation, progressing to severe mosaic by fifteen days post-inoculation, while Nicotiana glutinosa proved suitable for routine long-term maintenance of the virus cultures. Total RNA extracted from infected plants was subjected to reverse transcription polymerase chain reaction (RT-PCR) using coat protein gene-specific primers, which consistently amplified the expected 657 bp fragment from all six isolates. The amplified products were cloned into the pGEM-T Easy vector, transformed into Escherichia coli, confirmed by colony PCR and restriction digestion, and bidirectionally sequenced before submission to GenBank under accession numbers OQ756157, PV364315, PV364316, PV364319, PV364320, and PV370354.

Comparative nucleotide and deduced amino acid sequence analyses revealed a high degree of sequence conservation among the Bihar isolates, with sequence identity ranging from 95.8% to 100%. Several intra-study comparisons showed complete identity, particularly between Kahalgoan and Sabour, Purnia and Kasba, and Belwa and Purnia isolates, suggesting these isolates are either identical or differ by only single nucleotide substitutions. The limited variation was restricted to a few point mutations, indicating a highly conserved coat protein gene within the local CMV population. When compared with previously reported sequences, all isolates showed strong genetic affinity, exceeding 96% identity, with Indian CMV isolates such as MN341000.1, MN340995.1, and MN340989.1, and considerable similarity of around 97% with geographically distant isolates from Europe, Africa, and other parts of Asia, indicating strong global conservation of the coat protein gene. At the amino acid level, BLASTp analysis revealed only minor conservative substitutions with no major insertions, deletions, or frame-shift mutations.

Despite the overall conservation, the comparative analysis identified specific nucleotide substitutions at key positions. In the Sabour and Kahalgoan isolates, a cytosine was observed at nucleotide position 378, in contrast to the thymine found at the same position in the other isolates, a single nucleotide polymorphism that suggests a possible mutation unique to the isolates from these locations. At the protein level, a notable amino acid substitution was detected at position 173, where valine replaced methionine in the Kahalgoan isolate. Although limited in number, such substitutions may have biological significance, as the coat protein is a key determinant of virus encapsidation, vector transmission, host interaction, and viral evolution. Previous studies have demonstrated that even single amino acid substitutions in the coat protein can alter symptom expression, host response, and transmission efficiency, and the observed variation in the Bihar isolates may represent a region-specific adaptive response driven by host selection pressure and agro-climatic conditions in eastern India, although functional validation was not performed in this study.

Phylogenetic analysis based on the coat protein gene sequences grouped all six Bihar isolates within CMV subgroup IA, indicating close genetic relatedness with previously reported Indian CMV isolates. The evolutionary history was inferred using the Neighbor-Joining method with a dataset of 30 nucleotide sequences, including reference isolates from Thailand, Germany, Japan, Taiwan, and Italy, as well as CMV isolates from diverse hosts such as banana, jasmine, tobacco, capsicum, chilli, and tomato. Bootstrap analysis with 1,000 replications assessed the reliability of the tree topology. The clustering of Purnia, Kasba, Belwa, and Kharkhari isolates was supported by comparatively high bootstrap values, suggesting a recent common evolutionary origin with minimal genetic divergence, while Sabour and Kahalgoan formed a closely related cluster with high bootstrap support, reflecting stable phylogenetic association and probable localized spread within neighboring chilli-growing regions. The broader subgroup IA clade containing the Bihar isolates together with previously reported Indian and Asian isolates showed moderate bootstrap support, indicating reliable evolutionary grouping alongside gradual diversification among geographically separated CMV populations.

The observed sequence conservation suggests that CMV populations infecting chilli in Bihar are genetically stable and may have originated from a common ancestral source followed by regional dissemination. The low genetic diversity indicates a stable viral population, but the presence of minor sequence variation points to ongoing microevolution that may allow gradual adaptation to local hosts and environments. The widespread occurrence of CMV across multiple districts highlights the role of alternative hosts, weeds, and aphid vectors in maintaining virus reservoirs, and the virus’s broad host range facilitates its persistence in agro-ecosystems, making eradication impractical. The predominance of subgroup IA has significant implications for chilli improvement programs in Bihar: resistance breeding efforts should focus on screening germplasm against subgroup IA isolates, while integrated disease management involving virus-free seedlings, removal of weed reservoirs, and effective aphid vector management remains essential. Future studies should characterize additional genomic regions or pursue complete genome sequencing to obtain deeper insights into recombination events, strain evolution, and subgroup differentiation, and continuous molecular surveillance will be important for detecting the emergence of new variants under changing agro-climatic conditions.

Subject of Research: Molecular characterization and phylogenetic analysis of cucumber mosaic virus isolates infecting chilli in Zone II and Zone IIIB of Bihar, India, showing predominance of CMV subgroup IA with high coat protein gene conservation.

Article Title: Genetic diversity and characterization of cucumber mosaic virus infecting chilli in Zone II and Zone IIIB of Bihar, India

Article References: Kumar, M., Kumar, A., Shamim, M., Arzoo, K., & Srivastava, D. (2026). Genetic diversity and characterization of cucumber mosaic virus infecting chilli in Zone II and Zone IIIB of Bihar, India. Frontiers in Virology, 6, Article 1869218. https://doi.org/10.3389/fviro.2026.1869218

Image Credits: AI Generated

DOI: 10.3389/fviro.2026.1869218

Keywords: cucumber mosaic virus, chilli, Capsicum annuum, CMV subgroup IA, coat protein gene, DAC-ELISA, RT-PCR, phylogenetic analysis, genetic diversity, Bihar, plant virology, aphid transmission

Researchers at Hadhramout University in Mukalla, Yemen, conducted a retrospective cross-sectional study of 106 patients admitted to the COVID-19 isolation centers at Ibn-Sina Hospital between 1 December 2021 and 30 October 2022. The cohort comprised 63 men and 43 women with a mean age of 58.3 years, and all participants had presented with clinical suspicion of COVID-19 and undergone SARS-CoV-2 RT-PCR testing on nasal or oropharyngeal swabs. Of these, 58 patients, or 54.72 percent, tested positive and were classified as confirmed cases, while 48 patients, or 45.28 percent, tested negative and were classified as suspected cases. To guard against false negatives, patients with initial negative results were retested within 48 to 72 hours, a precaution the authors argue strengthens the reliability of the negative classification.

The study, published in Acta Biochimica Polonica, was designed to compare a panel of routine hematological and biochemical parameters between the two groups. The investigators extracted demographic, clinical, hematological, and biochemical data from electronic medical records and analyzed complete blood counts alongside random blood glucose, alanine transaminase, aspartate transaminase, lactate dehydrogenase, gamma-glutamyl transferase, C-reactive protein, and ferritin. Patients with known liver disease, renal disease, hematological disorders, autoimmune diseases, or malignancies were excluded, since any of these conditions could independently distort the laboratory picture and confound the comparison.

The hematological findings were striking. Compared with the RT-PCR-negative group, patients with confirmed COVID-19 had significantly higher hemoglobin, hematocrit, red blood cell counts, and white blood cell counts. Their neutrophil counts were markedly elevated, while lymphocyte and eosinophil counts were significantly reduced. This pattern, combining neutrophilia with lymphopenia and eosinopenia, mirrors what has been described repeatedly in confirmed COVID-19 cases worldwide and is thought to reflect the systemic inflammatory response triggered by SARS-CoV-2. Lymphopenia in particular has emerged as one of the most consistent hematological signatures of the disease, and reduced eosinophil levels have been linked to inflammatory activity and delayed recovery in prior reports.

Not every measured parameter moved in the same direction. Mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, platelet counts, monocyte counts, and basophil counts showed no statistically significant differences between the two groups. This selectivity is itself informative, suggesting that the laboratory changes associated with confirmed infection are not a nonspecific derangement of the blood but a characteristic pattern concentrated in the white cell differential and in the oxygen-carrying components. The authors note that hemoglobin and hematocrit were higher in the confirmed group, consistent with some previous studies, although other investigations have reported declining hemoglobin with increasing disease severity, a discrepancy the researchers attribute to differences in disease stage, patient characteristics, and underlying comorbidities.

The biochemical results were equally revealing. Serum levels of lactate dehydrogenase, gamma-glutamyl transferase, C-reactive protein, and ferritin were all significantly higher in the RT-PCR-positive group, with P values below 0.001 for each comparison. Random blood glucose was also elevated in the confirmed cases. By contrast, the liver transaminases ALT and AST did not differ significantly between the groups, despite earlier literature documenting hepatic involvement in COVID-19, with some studies reporting elevated transaminase activity in a substantial proportion of patients during the course of illness. The authors suggest that elevated LDH likely reflects tissue injury and systemic inflammation, while increased GGT points toward hepatobiliary involvement, though they acknowledge that previous findings on GGT in COVID-19 have been inconsistent, with some studies reporting no difference between confirmed and suspected cases.

To probe the relationships among these markers more deeply, the team performed Pearson correlation analysis within the RT-PCR-positive group. C-reactive protein correlated positively with AST, ALT, LDH, and GGT, and ferritin showed similar positive correlations with all four enzymes. The strongest associations were seen between the inflammatory markers and LDH and GGT, hinting at a coupling between systemic inflammation and the tissue or hepatobiliary injury these enzymes signal. This interlocking pattern of inflammation and organ-associated enzyme release reinforces the idea that the biochemical disturbances of COVID-19 are not isolated abnormalities but components of a coordinated pathological process.

The most consequential result emerged from the multivariable logistic regression analysis. When the significant biochemical variables were entered into a single model, only two markers remained independently associated with RT-PCR positivity: LDH, with an odds ratio of 1.008 per unit increase and a 95 percent confidence interval of 1.002 to 1.013 and a P value of 0.004, and GGT, with an odds ratio of 0.949, a 95 percent confidence interval of 0.903 to 0.997, and a P value of 0.039. CRP, despite its dramatic univariate elevation in confirmed cases, did not retain independent significance in the model. The direction of the GGT association, with higher values slightly reducing the odds of RT-PCR positivity, is counterintuitive and underscores the complexity of interpreting these markers in a multivariable framework.

The authors are careful to frame these findings appropriately. Because the study was retrospective and cross-sectional, the observed associations between LDH, GGT, and RT-PCR positivity cannot be interpreted as evidence of predictive or causal relationships. The regression model was built primarily from available laboratory parameters and did not account for all potential clinical confounders such as age, comorbidities, and disease severity, meaning residual confounding cannot be excluded. Moreover, the RT-PCR-negative group, though retested to reduce false negatives, was not systematically screened for alternative respiratory pathogens or other inflammatory conditions, so some of these patients may have had other infections or inflammatory diseases that influenced their laboratory profiles. The single-hospital design and modest sample size further limit generalizability, and clinical outcomes such as oxygen requirement, intensive care admission, and mortality were not available for all patients and could not be assessed.

Despite these caveats, the study offers a practical message for resource-constrained settings. The constellation of higher white cell and neutrophil counts, lower lymphocyte and eosinophil counts, and elevated LDH, GGT, CRP, and ferritin provides a recognizable laboratory fingerprint of confirmed COVID-19 that can be generated with standard hospital analyzers. In places where RT-PCR capacity is limited or turnaround times are long, such patterns may support clinical judgment while definitive testing is pending. The researchers call for prospective multicenter studies with larger cohorts, comprehensive clinical characterization, appropriate adjustment for confounding factors, and evaluation of patient outcomes to confirm these findings and determine whether LDH and GGT can ultimately earn a place alongside RT-PCR in the diagnostic toolkit for COVID-19 and beyond.

Subject of Research: Hematological and biochemical differences between RT-PCR-positive and RT-PCR-negative patients with suspected COVID-19 in Yemen

Article Title: Hematological and biochemical alterations in patients with suspected COVID-19 infection with negative and positive RT-PCR swabs

Article References: Bin Dahman, L. S., Bakarman, A. A., Al-Nakhbi, N. A., Al-Haddad, A. M., Bin-Talib, A. H., Al-Saadi, H. A., Bashatah, S. T., Al-Yazidi, N. S., Al-Houti, M. S., & Bin-Dheyab, M. O. (2026). Hematological and biochemical alterations in patients with suspected COVID-19 infection with negative and positive RT-PCR swabs. Acta Biochimica Polonica, 73, Article 16764. https://doi.org/10.3389/abp.2026.16764

Image Credits: AI Generated

DOI: 10.3389/abp.2026.16764

Keywords: COVID-19, SARS-CoV-2, RT-PCR, lactate dehydrogenase, gamma-glutamyl transferase, CRP, ferritin, lymphopenia, neutrophilia, Yemen, biomarkers, retrospective study

The variation in question is called rs53576, one of the most intensively studied single-nucleotide polymorphisms, or SNPs, in behavioral genetics. It is an A-to-G transition located in intron 3 of the OXTR gene, meaning it sits within a non-coding stretch of DNA that is spliced out of the final messenger RNA. Despite not altering the protein sequence directly, intronic variants like rs53576 can influence how the gene is expressed, how its RNA is processed, or how regulatory proteins bind. In the psychological literature, rs53576 has been linked to empathy, stress reactivity, and social behavior, with the G allele generally associated with higher oxytocin signalling efficiency. The new study flips the lens: instead of asking how the variant shapes personality, the researchers asked whether it shapes metabolic fate.

The rationale is grounded in physiology. Oxytocin receptors are expressed not only in the brain and uterus but also in pancreatic beta cells, adipose tissue, and skeletal muscle. Experimental work has shown that oxytocin can stimulate insulin release, promote lipid oxidation, and modulate hypothalamic circuits that govern appetite and energy expenditure. Conversely, oxytocin-deficient states in animal models are associated with obesity and impaired glucose tolerance, and intranasal oxytocin has been explored as an experimental anti-obesity therapy in humans. If the efficiency of oxytocin signalling varies from person to person because of genetic variation in the receptor, then it is biologically plausible that such variation could shift an individual’s susceptibility to type 2 diabetes mellitus, a disease defined by chronic hyperglycemia driven by insulin resistance and progressive beta-cell dysfunction.

To test this idea, the team designed a case-control genetic association study. They enrolled 200 patients with type 2 diabetes, each diagnosed according to American Diabetes Association criteria, which include a glycated hemoglobin level of 6.5 percent or higher, a fasting plasma glucose of at least 126 milligrams per deciliter, or a two-hour plasma glucose of at least 200 milligrams per deciliter during an oral glucose tolerance test. These patients were matched by age and sex with 200 normoglycemic controls. Ethical approval was obtained from the Institutional Review Board of Combined Military Hospital Kharian Medical College in Pakistan, and the study was conducted in accordance with the Declaration of Helsinki, with written informed consent from all participants. Genomic DNA was extracted from blood samples using the classical phenol-chloroform method, a robust if labor-intensive purification technique that remains a workhorse in molecular genetics laboratories.

The genotyping strategy is one of the more technically interesting aspects of the work. Rather than sequencing the entire gene, the researchers used a real-time polymerase chain reaction assay built around dual-labelled fluorescent hybridization probes, sometimes called FRET or HybProbe chemistry. In this setup, two short DNA probes bind adjacent to the rs53576 site during each amplification cycle. One probe carries a FAM fluorophore and is perfectly complementary to the A allele, while the other carries a HEX fluorophore and matches the G allele. When both probes are bound, energy transfer between them generates a fluorescence signal. The critical step comes afterward: a melting curve analysis, in which the temperature is slowly raised until each probe dissociates from its target. Because the A and G alleles differ by a single hydrogen bond, the two probes melt at slightly different temperatures, and the resulting melting peaks allow the instrument to assign each sample unambiguously as GG, AG, or AA. This approach is fast, closed-tube, and resistant to the carryover contamination that plagues some other genotyping formats.

The results from the patient group were striking. Among 99 evaluable type 2 diabetes patients, the GG genotype predominated, appearing in 64.65 percent of cases, and the G allele frequency reached 77.27 percent. In the preliminary control data available at the time of analysis, based on only five genotyped controls, the picture was almost inverted: just 40 percent carried the GG genotype and the G allele frequency was likewise 40 percent, while the AA genotype appeared in 60 percent of controls but only 10.10 percent of patients. That inverse distribution of the AA genotype, ten percent in cases against sixty percent in the small control sample, is what drove the researchers to suggest that the A allele might exert a protective effect against type 2 diabetes, or equivalently, that the G allele might confer increased susceptibility. Allele and genotype frequencies were compared using chi-square tests, and the association with diabetes risk and glycemic control, measured by HbA1c, was evaluated through logistic regression.

The headline statistic, however, demands careful reading. In the logistic regression comparing GG carriers against the combined AA and AG group, the odds ratio was 0.625, with a 95 percent confidence interval spanning 0.365 to 1.074 and a p-value of 0.087. In plain terms, the direction of the effect was consistent with the G allele being associated with diabetes, but the result did not reach the conventional threshold of statistical significance, and the confidence interval included the null value of one. The authors attribute this to a limitation they are transparent about: the control genotype data were available for only five individuals at the time of the reported analysis, a sample far too small to anchor a definitive association. An odds ratio of 0.625 estimated against five controls is, at best, a hypothesis-generating signal rather than a confirmed genetic risk factor. The team explicitly states that completion of the full control cohort and functional validation studies are required before any definitive conclusions can be drawn.

This candor matters, because genetic association studies have a troubled history when preliminary signals are overinterpreted. Candidate gene studies in diabetes have produced numerous associations that failed to replicate, and the field has learned to demand large cohorts, rigorous population matching, and independent replication before accepting a variant as genuinely risk-modifying. The rs53576 variant adds an extra layer of complexity because its allele frequencies differ substantially across world populations, and the present study was conducted in a Pakistani cohort, a population that remains underrepresented in genetic databases. Population stratification, in which differences in ancestry rather than biology drive apparent case-control differences, is a perennial concern in such designs, and the age- and sex-matching employed here addresses only part of that risk. The researchers’ decision to frame their findings as preliminary rather than conclusive is therefore scientifically appropriate.

Nevertheless, the biological plausibility of the hypothesis gives the finding genuine weight. If the G allele of rs53576 does enhance oxytocin receptor signalling, several mechanisms could plausibly connect it to glucose metabolism. Enhanced central oxytocin signalling might alter appetite regulation and body weight, both powerful determinants of diabetes risk. Direct effects on pancreatic beta cells could influence insulin secretion capacity, while effects on adipose tissue could shift the balance between lipid storage and oxidation. There is also the possibility of a more indirect pathway: chronic psychological stress is a recognized contributor to poor glycemic control, and oxytocin is a central mediator of stress buffering and social attachment. A variant that shapes how individuals respond to stress could, over decades, influence the neuroendocrine milieu in which glucose homeostasis is maintained. Disentangling these possibilities will require the functional validation studies the authors call for, ideally including expression analyses that test whether rs53576 genotype correlates with OXTR transcript levels in relevant tissues.

For now, the study stands as an intriguing early signal from an underexplored corner of diabetes genetics. It demonstrates that SNP-specific hybridization probe RT-PCR is a practical tool for interrogating oxytocin system variants in metabolic disease, and it establishes a preliminary genotype distribution in a South Asian diabetic population that differs markedly from the limited control data available. The work was funded by the Ongoing Researcher Funding Program at King Saud University in Riyadh, and its open-access publication means the raw genotype distributions are available for other groups to scrutinize and extend. Whether the love hormone’s receptor truly helps decide who develops type 2 diabetes will depend on completed cohorts, replication in independent populations, and laboratory evidence linking the intronic variant to receptor function. But the study succeeds in posing a question that endocrinology has largely ignored, and it does so with a methodological transparency that makes the next steps easy to define.

Subject of Research: Association between the oxytocin receptor gene polymorphism rs53576 and type 2 diabetes mellitus

Article Title: Investigating the association of the oxytocin receptor (OXTR) rs53576 SNP with type 2 diabetes using RT-PCR hybridization probe analysis

Article References: Hashmi, M. R. U. I., Sadiq, S., Hashmi, S. N., Zubair, R., Niazi, N. G., Shafique, H., Afsar, T., Aldisi, D., Ashraf, N. M., & Razak, S. (2026). Investigating the association of the oxytocin receptor (OXTR) rs53576 SNP with type 2 diabetes using RT-PCR hybridization probe analysis. BMC Endocrine Disorders. https://doi.org/10.1186/s12902-026-02522-5

Image Credits: AI Generated

DOI: 10.1186/s12902-026-02522-5

Keywords: oxytocin receptor, OXTR, rs53576, type 2 diabetes, SNP genotyping, RT-PCR, hybridization probes, melting curve analysis, genetic association study, insulin sensitivity, endocrinology, HbA1c

The research was carried out by Alok Kumar, Jean Hanson, Chris S. Jones, Fikerte Mulatu and Yilikal Assefa, all affiliated with the International Livestock Research Institute in Addis Ababa. Their motivation stemmed from a conspicuous gap in knowledge: although johnsongrass mosaic virus, commonly abbreviated JGMV, is recognized as an economically significant pathogen of grasses and cereals across the globe, its host range, genetic diversity and population structure in Ethiopian forage grasses had remained poorly understood. Forage grasses underpin livestock production in much of the region, so an uncharted viral landscape within these plants carried both scientific and agricultural implications. The team set out to identify which forage grass species in Ethiopia harbor the virus and to characterize the genetic diversity, population structure and evolutionary dynamics of the isolates circulating there.

The scale of the screening effort was considerable. The researchers examined a total of 949 forage grass accessions representing 33 genera, using a two-stage diagnostic strategy designed to balance throughput with specificity. The first stage employed a dot-blot assay, a technique in which plant tissue extracts are spotted onto a membrane and probed with virus-specific antibodies to reveal which samples carry viral proteins. Samples that tested positive in this serological screen were then subjected to reverse transcription polymerase chain reaction, or RT-PCR, using JGMV-specific primers designated GBV125F and GBV106R. These primers target the region of the viral genome encoding the coat protein, the structural protein that encapsidates the viral RNA and serves as a workhorse for potyvirus identification and classification.

The molecular confirmation was unambiguous. RT-PCR amplified the expected product of approximately 1.5 kilobases from samples corresponding to 249 accessions, which together represented 22 species across 10 genera. In other words, roughly a quarter of the screened accessions carried the virus, a prevalence that underscores how thoroughly JGMV has permeated the forage grass collections in Ethiopia. The researchers then selected representative isolates from this confirmed set for deeper genetic analysis, focusing on isolates drawn from 15 grass species belonging to six genera. Sequence analysis of these isolates confirmed JGMV infection in every case, and all fifteen species are now reported for the first time as natural hosts of the virus, a substantial expansion of the known host range of this pathogen.

The most consequential findings emerged when the team compared the amino acid sequences of the coat proteins of the Ethiopian isolates with those of JGMV isolates reported from around the world. The identity between Ethiopian isolates and international ones ranged from 70.4 percent to 81.1 percent, a range that sits uncomfortably close to, and in some cases below, the species demarcation threshold applied by the International Committee on Taxonomy of Viruses. The ICTV considers potyvirus isolates with coat protein amino acid identity above 80 percent to belong to the same species; values below that line suggest that the isolates may represent distinct species. The fact that some comparisons between Ethiopian and global isolates fell below this threshold means the Ethiopian virus population may be more than simply a geographically isolated branch of JGMV; it could represent distinct evolutionary lineages within the genus Potyvirus, a possibility the authors flag explicitly in their conclusions.

Phylogenetic analysis, which reconstructs the evolutionary relationships among virus isolates based on their sequences, grouped the JGMV isolates into three major clades. Within this framework, all of the Ethiopian isolates clustered together with isolates from Brazil in a distinct clade, separate from isolates collected elsewhere. This pattern is noteworthy because it links virus populations from two continents separated by the Atlantic Ocean, hinting at either shared ancestry, historical movement of virus or host material between the regions, or convergent evolutionary paths. The study does not resolve the mechanism behind this relationship, but the coherent clustering of Ethiopian isolates with Brazilian ones provides a clear phylogeographic signal that future work on virus dispersal will need to explain.

Population genetic analyses added further texture to the picture. The Ethiopian isolates exhibited high genetic diversity and significant genetic differentiation, indicating that the virus population in Ethiopia is both internally varied and substantially separated from populations elsewhere. Neutrality tests, statistical tools that compare the observed distribution of genetic variation with what would be expected under a neutral evolutionary model, provided evidence of historical population expansion, suggesting that the Ethiopian JGMV population has grown substantially at some point in its past. Such expansion is consistent with a virus that has successfully colonized a broad and abundant host landscape, and the fifteen newly identified host species offer ample substrate for continued diversification.

Recombination analysis revealed a further layer of complexity in the evolutionary history of the virus. Recombination, the exchange of genetic material between viral lineages, is a major driver of potyvirus evolution and can generate novel genotypes with altered host ranges or pathogenic properties. The analysis indicated that isolates from Ethiopia, Argentina, Brazil and Kenya were involved in recombination events, whereas isolates from the United States and Australia appeared relatively stable, showing no evidence of such exchanges. This geographic asymmetry suggests that recombination is not a uniform feature of the global JGMV population but rather concentrated in particular regions, with East Africa and South America emerging as hotspots of genetic exchange. For plant health authorities, recombination-prone populations are of particular interest because they can produce unexpected variants with the potential to overcome existing resistance in crop varieties.

The practical implications of the study extend beyond virology into the management of forage resources. Ethiopia’s forage grasses are central to livestock agriculture, and germplasm collections maintained for breeding and conservation purposes can inadvertently serve as reservoirs of viral pathogens if infection goes undetected. The finding that 249 of 949 accessions were positive for JGMV, spanning 22 species and 10 genera, illustrates how extensively the virus has infiltrated the forage gene pool in the country. The identification of fifteen new natural host species broadens the range of plants through which the virus can persist and move, complicating efforts to manage its spread. Because the study was funded by the CGIAR Research Program for Managing and Sustaining Crop Collections, and drew on antiserum for detecting Brachiaria-infecting potyviruses provided by the International Center for Tropical Agriculture, it reflects the kind of collaborative infrastructure that international agricultural research centers maintain to safeguard plant genetic resources.

The authors are careful to frame their conclusions as a foundation rather than a final word. The substantial divergence observed among the Ethiopian isolates suggests the possible emergence of distinct evolutionary lineages within the genus Potyvirus, but confirming whether these isolates warrant recognition as separate species will require complete genome sequencing rather than analysis of the coat protein region alone. The team also highlights the need for vector transmission studies to clarify how the virus moves among its hosts in the field, knowledge that is essential for assessing its epidemiological significance and designing control strategies. Until such work is done, the study stands as a vivid demonstration of how much viral diversity can remain hidden within a region’s plant collections, and of the value of systematic screening paired with molecular characterization. For Ethiopia’s forage grasses, and for the broader community studying potyvirus evolution, the message is clear: the virus population in East Africa is widespread, genetically rich, and evolutionarily distinctive enough to demand closer attention.

Subject of Research: Detection and genetic diversity of johnsongrass mosaic virus in Ethiopian forage grasses

Article Title: Detection and genetic diversity of johnsongrass mosaic virus isolates infecting fifteen new forage grass hosts in Ethiopia

Article References: Kumar, A., Hanson, J., Jones, C. S., Mulatu, F., & Assefa, Y. (2026). Detection and genetic diversity of johnsongrass mosaic virus isolates infecting fifteen new forage grass hosts in Ethiopia. BMC Plant Biology. https://doi.org/10.1186/s12870-026-10002-0

Image Credits: AI Generated

DOI: 10.1186/s12870-026-10002-0

Keywords: johnsongrass mosaic virus, Potyvirus, Ethiopia, forage grasses, RT-PCR, coat protein, genetic diversity, phylogenetics, recombination, ICTV species demarcation, plant virus epidemiology, germplasm screening

Chronic lymphocytic leukaemia, or CLL, is a malignancy characterised by the progressive accumulation of monoclonal lymphocytes bearing a distinctive immunophenotype — cells that are CD5-positive, CD19-positive, CD20-dim, CD23-positive and express dim surface immunoglobulin — in the peripheral blood, bone marrow and lymphoid tissues. Unlike many other chronic lymphoproliferative disorders, CLL is defined as much by its immunological consequences as by its malignant ones. Patients frequently present with immune disturbances and recurrent infections, a feature that makes the disease particularly dangerous in the era of a novel respiratory virus. The leukaemic cells crowd out functional immune components, and the humoral arm of the immune system is often left strikingly weakened.

The patient in this report had been diagnosed with CLL four years before she presented with fever. For the two years preceding her COVID-19 illness, she had been receiving ibrutinib, a targeted Bruton tyrosine kinase inhibitor used as maintenance therapy. While ibrutinib has transformed the management of CLL, it adds another layer of immunosuppression to a disease already defined by immune dysfunction. When her symptoms began, a computed tomography scan of the chest revealed a pattern of ground-glass opacities, the hazy radiological signature familiar to clinicians throughout the pandemic, and RT-PCR testing confirmed SARS-CoV-2 infection.

What followed was a clinical course that departed sharply from the expected trajectory. Two weeks after the patient had clinically recovered, repeat RT-PCR testing remained positive. Twenty-eight days later, she returned to medical attention with fever and weakness. On admission, her clinicians discontinued ibrutinib, a common practice for patients with COVID-19 intended to minimise potential drug-related complications and reduce the burden of immunosuppression. She was treated with dexamethasone to manage inflammation and remdesivir as antiviral therapy, both standard interventions for hospitalised COVID-19 patients aimed at curbing viral replication and blunting the cytokine-driven tissue damage that characterises severe disease.

Despite this conventional therapeutic arsenal, the virus would not retreat. Serial RT-PCR tests performed on nasopharyngeal aspirates continued to detect the SARS-CoV-2 genome, with positivity persisting up to 127 days after symptom onset. Throughout this period, the patient remained under quarantine and home observation. Laboratory findings captured the depth of her illness: a white blood cell count of 50 × 10⁹ per litre with 88 percent lymphocytes, reflecting the leukaemic burden; a C-reactive protein level of 200 mg/L and an erythrocyte sedimentation rate of 119 mm/hour, markers of vigorous systemic inflammation; and elevated liver enzymes, with alanine aminotransferase at 87 U/L and aspartate aminotransferase at 75 U/L. Eventually, on day 127, her oxygen saturation declined, and she died in the intensive care unit.

The authors of the report attribute this extraordinary duration of viral shedding to the profound immunodeficiency associated with CLL, further compromised by ongoing chemotherapy and ibrutinib therapy. Central to this vulnerability is hypogammaglobulinemia, a hallmark of CLL in which levels of protective antibodies — IgG, IgA and IgM — fall below the thresholds needed for effective host defence. These immunoglobulins are crucial for neutralising SARS-CoV-2 and preventing its dissemination within the body. When the humoral immune system cannot mount a competent antibody response against the virus, viral replication proceeds unchecked, and shedding continues for months rather than weeks. The patient’s failure to seroconvert, noted by the authors, aligns with a growing body of evidence showing that CLL patients mount suboptimal antibody responses to SARS-CoV-2 infection.

This immunological failure helps explain a broader and troubling pattern. Early reports from China indicated that individuals with cancer are more susceptible to SARS-CoV-2, although initial data on the prevalence and features of COVID-19 across different cancers, including CLL, were limited. Subsequent studies have shown that patients with CLL are more likely to experience severe COVID-19, with higher rates of hospitalisation, intensive care unit admission and mortality compared to the general population. Advanced age compounds the risk, and this patient’s 69 years, combined with ongoing chemotherapy, placed her in a particularly precarious position. Prolonged viral shedding has been documented in other immunocompromised individuals as well, but the distinguishing feature of this case, according to the authors, is the demonstration that early cessation of targeted therapy combined with standard antiviral and corticosteroid administration was entirely insufficient to halt continuous viral replication, ultimately leading to fatal hypoxemia by day 127.

The case also raises uncomfortable questions about the limits of standard COVID-19 therapy in immunocompromised hosts. Remdesivir, a nucleotide analogue prodrug that inhibits viral RNA-dependent RNA polymerase, and dexamethasone, a corticosteroid that dampens the inflammatory cascade, were developed and validated largely in populations with intact immune systems. In a patient who cannot generate neutralising antibodies, the report suggests, these treatments may not suffice to achieve viral clearance. The authors point instead to monoclonal antibodies such as casirivimab and imdevimab, which have shown promise in facilitating rapid viral clearance in CLL patients grappling with persistent infections. By supplying exogenous neutralising antibodies, such therapies can in principle substitute for the humoral response the patient’s own body cannot mount, offering a potential therapeutic avenue where conventional regimens fall short.

Supportive measures aimed at correcting the underlying antibody deficiency may hold similar promise. The authors highlight intravenous immunoglobulin infusions, which replenish circulating IgG and can provide passive immunity against a broad range of pathogens, as an intervention that may improve outcomes among CLL patients infected with SARS-CoV-2. Cited literature includes a reported case of long-lasting SARS-CoV-2 infection with post-COVID-19 chronic interstitial pneumonia in a CLL patient treated successfully with intravenous immunoglobulin, suggesting that addressing hypogammaglobulinemia directly can alter the course of otherwise intractable infections. Robust monitoring of viral shedding in such patients is also emphasised, both to guide therapy and to minimise potential transmission risks from prolonged carriers — a public health consideration, since immunocompromised individuals who harbour replicating virus for months are also environments in which new variants can emerge.

The report’s authors conclude that the prevalence, clinical characteristics and outcomes of COVID-19 in CLL patients have yet to be fully established, and that preliminary data from large patient series remain valuable for understanding and managing these cases. Their central message is a call for tailored strategies that go beyond remdesivir and dexamethasone, particularly given the high mortality linked to comorbidities in this population. For clinicians, the case is a reminder that a positive RT-PCR test in an immunocompromised patient is not merely a lingering molecular echo of a resolved infection; it can reflect genuinely ongoing viral replication. For virologists, it is a vivid demonstration of the delicate equilibrium between host immunity and viral persistence — an equilibrium that, when the immune system fails, can stretch a two-week illness into a 127-day ordeal with a fatal end.

Subject of Research: Prolonged SARS-CoV-2 RNA shedding in a chronic lymphocytic leukaemia patient with impaired antibody responses

Article Title: Persistent SARS‐CoV‐2 RNA Positivity in a Chronic Lymphocytic Leukaemia Patient for 127 Days After Disease Onset: A Case Report

Article References: Khamseh, F., Moghtader‐Mojdehi, A.-H., Nemati, Z., & Haghighi, M. (2026). Persistent SARS ‐ CoV ‐2 RNA Positivity in a Chronic Lymphocytic Leukaemia Patient for 127 Days After Disease Onset: A Case Report. Respirology Case Reports, 14(10), Article e70767. https://doi.org/10.1002/rcr2.70767

Image Credits: AI Generated

DOI: 10.1002/rcr2.70767

Keywords: SARS-CoV-2, chronic lymphocytic leukaemia, viral shedding, immunodeficiency, hypogammaglobulinemia, ibrutinib, remdesivir, dexamethasone, RT-PCR, monoclonal antibodies, COVID-19, case report

The research, conducted at Shohadaye-Khalije-Fars Teaching Hospital in Bushehr and published in BMC Infectious Diseases, examined the medical records of 428 hospitalized patients with RT-PCR-confirmed SARS-CoV-2 infection admitted during 2020, all of whom underwent at least one chest HRCT scan during their stay. Across this cohort, a total of 463 HRCT examinations were performed. The researchers, led by Atefeh Esfandiari and Hedayat Salari of Bushehr University of Medical Sciences, judged each scan against the indications laid out in the Iranian national COVID-19 guidelines, using a structured checklist to extract clinical data from the charts. By these criteria, 188 of the 463 scans, or 40.6 percent, were classified as inappropriate.

The distinction between appropriate and inappropriate imaging rests on well-established principles of radiological stewardship. Reverse transcription polymerase chain reaction remains the reference standard for diagnosing SARS-CoV-2 infection, detecting viral RNA with high specificity. HRCT is meant to serve as a complementary tool, reserved for situations such as diagnostic uncertainty, suspected complications, or significant deterioration in a patient’s respiratory status. When a scan is ordered outside these documented indications, the patient absorbs ionizing radiation without a corresponding benefit, and the health system absorbs the cost. The American College of Radiology and similar bodies worldwide have long warned that indiscriminate imaging of this kind erodes both safety and economic efficiency.

To understand why so many scans fell outside guideline recommendations, the team turned to multivariable logistic regression, a statistical technique that isolates the independent effect of each potential predictor while controlling for the others. The results were striking. The strongest driver of inappropriate ordering was symptom duration of seven days or less at the time the scan was requested, with an adjusted odds ratio of 47.15 and a p-value below 0.001. In practical terms, patients scanned very early in the course of illness were dramatically more likely to have been imaged without a guideline-supported reason, a pattern consistent with clinicians reaching for CT before the disease’s characteristic radiological evolution had even had time to develop.

Two other independent predictors emerged from the analysis. Requests originating from hospital-based general practitioners working in the emergency department carried an adjusted odds ratio of 9.64 for inappropriateness, compared with requests from subspecialists, suggesting that the ordering physician’s level of training shaped adherence to imaging criteria. Patient age also mattered: those younger than 30 years faced an adjusted odds ratio of 8.97 for receiving an inappropriate scan relative to patients older than 65. Younger patients with COVID-19 generally have milder disease and lower baseline risk, which may explain why imaging them often lacked a defensible clinical indication, yet the scanners were still frequently rolled out.

Repeat imaging added another layer of concern. Among the 35 repeat HRCT examinations performed during the study period, 12 were judged inappropriate. Serial chest CT is sometimes justified to track disease progression or response to therapy, but each additional scan compounds the cumulative radiation dose. In the context of a respiratory illness where many follow-up scans yield little actionable information, the finding underscores how easily a resource-intensive test can become routine rather than reasoned.

The economic analysis translated these clinical lapses into monetary terms, calculated from three distinct perspectives. The unnecessary financial burden attributable to inappropriate HRCT utilization was estimated at 56,047,000 Iranian rials, approximately 2,156 US dollars, borne by patients themselves. From the governmental healthcare system perspective, the burden rose to 182,360,000 rials, roughly 7,014 US dollars. Under the private tariff, the figure climbed to 328,812,000 rials, or about 12,646 US dollars. While these sums may appear modest in absolute global terms, they represent pure waste, expenditure on imaging that delivered no clinical value, and they scale rapidly when projected across the thousands of hospitals and millions of admissions that defined the pandemic era.

The study’s methodology deserves attention for what it reveals about health services research during public health emergencies. As a retrospective, analytical, cross-sectional investigation conducted in 2022, it reviewed records rather than prospectively guiding care, which means the findings describe practice as it happened rather than testing an intervention. Descriptive statistics and chi-square or Fisher’s exact tests were used to compare groups, and the appropriateness judgment depended on documented clinical indications in the chart, an approach that ties the assessment to the paper trail each ordering clinician left behind. The work was approved by the ethics committee of Bushehr University of Medical Sciences, with informed consent waived due to the retrospective design and all patient data fully anonymized.

Why does this matter beyond a single hospital in Bushehr? The pandemic placed unprecedented pressure on diagnostic infrastructure everywhere, and the temptation to image broadly, to see what the lungs looked like rather than to answer a specific clinical question, was felt in emergency departments across the globe. Guidelines from national health authorities and professional societies consistently urged restraint, recommending CT primarily when RT-PCR results were unavailable or discordant with clinical findings, or when complications were suspected. The Iranian data provide a quantified case study of what happens when that restraint slips: more than four in ten scans ordered without indication, a clear gradient of risk tied to early symptom duration, junior ordering patterns, and young age, and a measurable bill attached to every unnecessary exposure.

The authors conclude that strengthening adherence to evidence-based imaging indications could reduce unnecessary utilization without compromising clinical care. Their findings point toward practical remedies: decision-support tools embedded in electronic ordering systems, clearer escalation pathways that involve subspecialist judgment before advanced imaging, and audit-and-feedback mechanisms that show clinicians how their ordering behavior compares with guideline expectations. As health systems worldwide continue to digest the lessons of COVID-19, the Bushehr study offers a reminder that the cost of a pandemic is measured not only in lives and lockdowns but also in the quiet accumulation of tests that were never needed, doses of radiation that were never justified, and funds that could have strengthened care elsewhere.

Subject of Research: Clinical appropriateness and economic burden of high-resolution chest CT scanning in hospitalized COVID-19 patients

Article Title: Evaluating the clinical appropriateness of high-resolution chest CT scans in hospitalized patients with COVID-19 and the economic burden: a retrospective study in southern Iran

Article References: Esfandiari, A., Amiri, B., Abbasi, F., Esfandiari, S., & Salari, H. (2026). Evaluating the clinical appropriateness of high-resolution chest CT scans in hospitalized patients with COVID-19 and the economic burden: a retrospective study in southern Iran. BMC Infectious Diseases. https://doi.org/10.1186/s12879-026-14582-y

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14582-y

Keywords: COVID-19, SARS-CoV-2, high-resolution computed tomography, HRCT, RT-PCR, medical imaging, imaging appropriateness, healthcare costs, radiation exposure, Iran, retrospective study, clinical guidelines

Lassa fever presents a formidable diagnostic challenge. Early symptoms, including fever, malaise, headache, and muscle pain, overlap substantially with malaria, typhoid fever, and other common febrile illnesses that dominate the clinical landscape of the region. As a result, many infections are treated empirically as malaria and never confirmed as Lassa, obscuring the true burden of disease and delaying interventions such as isolation, contact tracing, and timely administration of ribavirin, the antiviral most often used in management. Case fatality is highest among patients hospitalized late in illness, which makes early laboratory confirmation not merely an academic exercise but a direct determinant of survival.

Historically, suspected cases in Forest Guinea had to be referred to distant reference laboratories, often outside the country, for confirmatory testing. Transport of samples over long distances on poor roads introduced delays of days or weeks, degraded sample quality, and severed the connection between laboratory results and the clinical decisions that needed to inform them. During that interval, patients could deteriorate, contacts could be exposed, and outbreak signals could be missed entirely. Strengthening in-country and, ultimately, in-region diagnostic capacity has therefore been a central pillar of Guinea’s post-epidemic health security agenda, accelerated by the hard lessons of the 2014–2016 Ebola virus disease epidemic in West Africa.

The advances described in the study center on the establishment and progressive improvement of laboratory platforms capable of detecting Lassa virus and other hemorrhagic fever pathogens at or near the point of patient care. Molecular assays based on reverse transcription polymerase chain reaction (RT-PCR) remain the reference standard for acute case confirmation, targeting conserved regions of the viral S segment genome. Deploying these assays in Guinea required not only equipment and reagents but also reliable cold chains, uninterrupted power supply, quality management systems, and, critically, trained personnel able to perform testing to internationally recognized standards.

Serological methods complement molecular detection in the diagnostic arsenal. Indirect immunofluorescent antibody tests and enzyme-linked immunosorbent assays detecting Lassa-specific IgM and IgG antibodies extend the window of detection beyond the viremic phase and support seroprevalence studies that map the footprint of past transmission. Because antibody responses in Lassa fever can be variable and cross-reactivity with other arenaviruses complicates interpretation, the combination of molecular and serological approaches, applied with careful clinical context, provides the most complete picture of who is infected, who has been exposed, and where the virus is actively circulating.

A decisive element of the capacity-building effort has been the training of Guinean laboratory scientists and technicians in biosafe specimen handling, nucleic acid extraction, assay execution, and result interpretation. Working with Lassa virus requires appropriate biosafety precautions, since the virus can be transmitted through contact with infectious blood, tissues, or bodily fluids, and laboratory-acquired infections are a recognized occupational risk. Building a cadre of locally based experts reduces dependence on external missions, sustains testing throughput between outbreaks, and anchors diagnostic capability within the national public health system rather than in temporary emergency structures.

The study documents how these investments translated into operational gains: more suspected cases tested, shorter turnaround times between sample collection and result reporting, and a higher proportion of Lassa fever cases confirmed within the country. Each of these metrics matters. Faster confirmation enables clinicians to initiate appropriate treatment earlier, triggers more rapid deployment of outbreak response teams, and improves the accuracy of surveillance data used to allocate scarce resources. Improved detection also feeds back into research, since confirmed cases provide the samples and epidemiological context needed to study viral diversity, disease severity, and transmission dynamics.

Genomic surveillance is an increasingly important downstream benefit of strengthened diagnostics. Sequencing Lassa virus genomes from confirmed cases allows researchers to track viral lineages, identify introductions from rodent reservoirs into human populations, and reconstruct transmission chains. In Forest Guinea, where multiple Lassa virus lineages are known to circulate and where the ecological interface between humans and reservoir rodents is intimate, genomic data can distinguish persistent local transmission from repeated spillover events, information that shapes whether interventions should prioritize rodent control, food storage hygiene, community education, or vaccination once candidate vaccines advance through the pipeline.

The Guinea experience also carries lessons for regional health security more broadly. The same laboratory infrastructure, trained workforce, and specimen referral networks that support Lassa fever detection can be adapted for other viral hemorrhagic fevers, including Ebola, Dengue, and yellow fever, as well as for emerging pathogens of unknown origin. Integrated diagnostic platforms that can pivot between pathogens represent a more resilient investment than single-disease silos, a principle reinforced by the COVID-19 pandemic, which tested and in many places benefited from hemorrhagic fever diagnostic networks established in the preceding decade.

Challenges remain. Sustaining funding beyond donor-supported emergency cycles, maintaining reagent supply chains, retaining skilled staff, and expanding testing to peripheral health facilities all require continued commitment. Yet the trajectory documented in Forest Guinea demonstrates that endemic countries can move from being sample-shippers to being diagnostic leaders in the fight against viral hemorrhagic fevers. Every Lassa fever case confirmed quickly and accurately is a patient treated sooner, a contact list initiated earlier, and a piece of evidence added to the regional understanding of one of West Africa’s most persistent viral threats.

Subject of Research: Strengthening diagnostic capacity for Lassa fever and viral hemorrhagic fevers in Forest Guinea

Article Title: Strengthening diagnostic capacity for viral hemorrhagic fevers in Forest Guinea: advances in Lassa fever case detection

Article References: Koundouno, F. R., Sidibe, Y., Millimono, S. L., Ifono, K., Hinzmann, J., Soubrier, H., Kourouma, K., Millimouno, T. E., Tolno, F. M., Kamano, F. M., Barry, M. D., Koulemou, S., Sonomy, B., Traore, M., Keïta, K., Hinrichs, M., Ryter, S., van Gelder, C., Becker-Ziaja, B., … Annibaldis, G. (2026). Strengthening diagnostic capacity for viral hemorrhagic fevers in Forest Guinea: advances in Lassa fever case detection. npj Viruses, 4(1), Article 42. https://doi.org/10.1038/s44298-026-00239-9

Image Credits: AI Generated

DOI: 10.1038/s44298-026-00239-9

Keywords: Lassa fever, viral hemorrhagic fevers, diagnostic capacity, Forest Guinea, RT-PCR, serology, genomic surveillance, biosafety, public health laboratory, case detection, outbreak response, Strengthening

At the molecular level, the circulating strain belongs to the family Orthomyxoviridae and carries a negative-sense, single-stranded, segmented RNA genome that encodes the structural and non-structural proteins required for its replication cycle. The two primary surface glycoproteins, hemagglutinin and neuraminidase, govern the critical steps of host cell attachment, viral entry, and release of progeny virions. Hemagglutinin binds to alpha-2,6-linked sialic acid receptors, which are abundantly expressed on human upper respiratory epithelial cells, anchoring the virus to its preferred portal of entry. Once attached, the virion is taken up by receptor-mediated endocytosis, and the low pH of the endosome triggers a conformational change in hemagglutinin that fuses the viral envelope with the endosomal membrane. This allows uncoating of the viral ribonucleoprotein complexes and their import into the host cell nucleus, where the viral RNA-dependent RNA polymerase executes replication and transcription. Neuraminidase then cleaves terminal sialic acid residues from the host cell surface, preventing newly formed virions from aggregating and permitting efficient budding and dissemination throughout the respiratory tract.

Environmental conditions in the National Capital Region play a decisive role in shaping transmission dynamics, and they differ sharply from the patterns seen in temperate climates. Rather than producing a single crisp winter peak, northern India experiences seasonal viral persistence predisposed by high ambient humidity, monsoon precipitation, and subsequent winter thermal inversions that trap polluted air close to the ground. High humidity and poor air circulation in enclosed spaces facilitate the stability and transport of fine micro-aerosols alongside the larger respiratory droplets generated by coughing, sneezing, and even vocalization. Indoor crowding during spells of inclement weather increases close-contact exposure, while contaminated environmental surfaces serve as secondary vectors for indirect mucosal self-inoculation when people touch their faces after contact with contaminated fomites. Following exposure, the virus exhibits an incubation period of roughly one to four days, a window during which asymptomatic or presymptomatic viral shedding can seed community transmission chains well before the first overt clinical presentation, complicating efforts to contain spread through symptom-based screening alone.

The clinical spectrum of A(H1N1) infection ranges from mild, uncomplicated upper respiratory illness to fulminant, life-threatening systemic disease. Typical uncomplicated cases present with abrupt-onset fever, non-productive cough, pharyngeal erythema, nasal congestion, severe retro-orbital or generalized headache, diffuse myalgia, and profound constitutional fatigue. Pediatric cohorts frequently show prominent gastrointestinal involvement, including nausea, vomiting, and diarrhea, layered on top of systemic febrile illness. In a subset of patients, viral tropism for the lower respiratory tract precipitates rapid tissue damage, characterized by necrotizing tracheobronchitis, diffuse alveolar damage, impaired gas exchange, and eventual acute respiratory distress syndrome. Viral destruction of the respiratory epithelium also strips away a critical innate barrier, leaving the lower airways highly vulnerable to secondary bacterial superinfections, most notably those caused by Streptococcus pneumoniae, Staphylococcus aureus, and Streptococcus pyogenes. These bacterial complications historically account for a substantial share of influenza-related morbidity and mortality, which is why clinicians are urged to watch for clinical deterioration beyond the expected viral course.

Identifying high-risk populations is central to early intervention and rational allocation of scarce clinical resources. Pregnant women represent an exceptionally vulnerable cohort because physiological alterations in cell-mediated immunity, decreased chest wall compliance, and elevated maternal oxygen consumption collectively heighten the risk of rapid pulmonary decompensation. The extreme age groups face elevated danger as well: infants under five years experience heightened morbidity because of immature immune responses, while adults aged sixty-five and older are compromised by immunosenescence, the gradual decline of immune function with age. Individuals with underlying chronic comorbidities, including diabetes mellitus, chronic obstructive pulmonary disease, bronchial asthma, congestive heart failure, chronic renal insufficiency, hepatic dysfunction, neurological disorders, morbid obesity, and active immunosuppression, face significantly higher rates of hospitalization, intensive care unit admission, and death. For these groups, clinicians emphasize that even seemingly mild respiratory symptoms early in an influenza wave warrant a low threshold for testing and antiviral treatment.

Clinical monitoring during the surge must emphasize rapid detection of red-flag indicators that signal acute physiological deterioration. In adults, key warning signs requiring immediate emergency evaluation include progressive dyspnea, tachypnea, persistent central chest pressure, low peripheral oxygen saturation, central cyanosis, acute alteration of mental status, persistent high fever unresponsive to antipyretics, or a clinical relapse following transient symptom resolution. That last pattern, a biphasic worsening after apparent improvement, is particularly concerning because it often heralds secondary bacterial pneumonia. In pediatric patients, critical warning indicators include intercostal retractions, grunting, nasal flaring, lethargy, poor oral fluid intake leading to dehydration, persistent irritability, and breakthrough febrile seizures. Prompt recognition of these signs facilitates timely admission to higher-level care facilities capable of providing advanced respiratory support, including oxygen therapy and mechanical ventilation, which can be decisive in severe lower respiratory tract disease.

Definitive clinical management, the analysis stresses, relies on rigorous diagnostic testing and targeted pharmacological therapy rather than empirical broad-spectrum interventions. Reverse transcription-polymerase chain reaction remains the gold standard diagnostic technique for hospitalized or severe cases, enabling accurate differentiation of H1N1 from co-circulating respiratory pathogens such as SARS-CoV-2, respiratory syncytial virus, adenovirus, and bacterial pneumonia. This differential matters because treatment pathways diverge sharply: antivirals benefit influenza, whereas antibacterial agents are clinically ineffective against a primary viral pathogen and contravene global antimicrobial stewardship principles when used empirically. The authors are emphatic that antibiotics should be strictly reserved for cases with confirmed or highly suspected secondary bacterial co-infections, a discipline that protects both individual patients from unnecessary drug exposure and the broader community from accelerating antimicrobial resistance, an already serious problem in South Asian healthcare settings.

On the therapeutic front, neuraminidase inhibitors, particularly oral oseltamivir, form the cornerstone of antiviral therapy for patients with severe, progressive, or complicated disease, as well as for all high-risk individuals presenting with respiratory illness during the surge. Timing is critical: antiviral treatment provides optimal benefit when initiated within 48 hours of symptom onset, significantly dampening viral replication, shortening the duration of illness, and lowering the incidence of severe complications. Meta-analytic evidence from hospitalized H1N1pdm09 cohorts has linked early neuraminidase inhibitor use with reduced mortality, reinforcing the case for prompt empirical treatment of high-risk patients even before laboratory confirmation returns. Because the drug targets the neuraminidase protein rather than the hemagglutinin antigen that drifts seasonally, it retains activity against the A/Missouri/11/2025-like variant now circulating in India, providing a reliable pharmacological backstop while vaccination programs catch up.

Prevention, ultimately, remains the most cost-effective strategy, and the authors outline a comprehensive, layered framework. Annual seasonal influenza vaccination sits at its core, with the current vaccine exhibiting strong antigenic concordance with the circulating A(H1N1)pdm09 clade, a consequence of the World Health Organization’s strain selection for the 2025-2026 Northern Hemisphere season. Around that pharmacological anchor, the framework integrates non-pharmaceutical interventions: home isolation of symptomatic individuals, frequent hand hygiene, respiratory etiquette, enhanced indoor ventilation, and the use of well-fitted N95 respirators in high-density environments such as public transport, markets, and healthcare facilities. For a densely populated tropical and subtropical megaregion where monsoon humidity and winter thermal inversions prolong viral viability, these measures collectively reduce the effective reproduction number of the virus. The 2026 surge, the analysis concludes, is a reminder that seasonal influenza remains a formidable and recurring public health threat, but one whose trajectory can be substantially blunted by surveillance, vaccination, judicious antiviral use, and disciplined antimicrobial stewardship.

Subject of Research: The 2026 seasonal resurgence of influenza A(H1N1)pdm09 in India and evidence-based strategies for its prevention and clinical management

Article Title: H1N1 seasonal surge in India, 2026: Emerging public health threat and evidence based preventive strategies

Article References: Choudhary, O. P., & Choudhary, P. (2026). H1N1 seasonal surge in India, 2026: Emerging public health threat and evidence based preventive strategies. New Microbes and New Infections, 73, Article 101836. https://doi.org/10.1016/j.nmni.2026.101836

Image Credits: AI Generated

DOI: 10.1016/j.nmni.2026.101836

Keywords: H1N1, influenza A(H1N1)pdm09, India, Delhi-NCR, seasonal influenza, oseltamivir, neuraminidase inhibitors, influenza vaccination, RT-PCR, respiratory transmission, public health surveillance, antimicrobial stewardship