The research team, led by Manel Mansouri of the Institute of Urban and Environmental Technology Management at the University of Saleh Boubnider Constantine 3, together with Brahim Brahamia and Nabil Mega of the University of El Oued, conducted a retrospective observational cross-sectional study using routinely collected surveillance data from Khenchela Provincial Hospital. Their dataset comprised 652 laboratory-confirmed HCV cases recorded between January 2018 and December 2022. From each medical record, the team extracted demographic information, clinical details, and geographical data, allowing them to link every confirmed infection to the municipality in which the patient resided. This geographic anchoring of clinical data is what made the subsequent spatial analysis possible, and it reflects a growing recognition in epidemiology that where a disease occurs can be as informative as who it affects.

Methodologically, the study employed a two-stage spatial statistical approach that has become a standard of rigor in disease mapping. First, the researchers applied Global Moran’s I, a statistic that tests whether the overall spatial pattern of HCV incidence across the province deviates from randomness. A significant result from this test indicates that neighboring municipalities tend to have similar incidence rates, a phenomenon known as spatial autocorrelation, and justifies the search for localized clusters. The team then deployed the Getis-Ord Gi* statistic, run with a fixed distance band and 999 permutations, to pinpoint exactly where those clusters lie. The Gi* statistic works by comparing the local sum of values for a municipality and its neighbors with the expected sum under a random distribution; when the observed concentration is far higher than chance would predict, the area is flagged as a hotspot, with confidence levels expressed through Gi_Bin scores ranging from 90 percent to 99 percent certainty.

The results were striking. Four municipalities emerged as statistically significant hotspots of HCV incidence. Ouled Rechache showed the strongest signal, with a Gi_Bin value of +3 corresponding to 99 percent confidence and an incidence rate of 43.7 cases per 100,000 population. Ain Touila followed with a Gi_Bin of +2 at 95 percent confidence and a rate of 32.7 per 100,000. El Mahmel and Ensigha were each identified at 90 percent confidence with Gi_Bin values of +1, though their incidence profiles differed dramatically: El Mahmel recorded 74.7 cases per 100,000, the highest absolute rate in the province, while Ensigha registered only 3.5 per 100,000. The authors emphasize that Ensigha’s inclusion reflects statistical significance rather than a high case burden, a nuance that matters greatly for interpretation. In sparsely populated areas, even a small number of cases can produce a statistically unusual local concentration, whereas El Mahmel’s elevated rate represents a genuinely heavy transmission load.

Complementing the hotspot findings, the analysis identified two cold spots, Remila and Kais, each at 90 percent confidence with Gi_Bin values of −1. Cold spots are areas where incidence is significantly lower than the provincial norm, and their identification is more than a statistical footnote. By contrasting the demographic, healthcare, and environmental characteristics of hotspots and cold spots, public health officials can generate hypotheses about what drives transmission in high-incidence areas and what protective factors may operate elsewhere. In a province where resources for screening, counseling, and antiviral treatment are limited, such contrasts provide an evidence-based rationale for prioritization rather than relying on uniform, untargeted campaigns that dilute impact across the entire population.

Beyond geography, the demographic and clinical profile of the 652 cases revealed patterns with direct implications for prevention. Women accounted for 60.6 percent of confirmed infections, or 395 cases, compared with 39.4 percent for men, or 257 cases. The age distribution was heavily skewed toward middle age: people aged 46 to 60 years made up 37.7 percent of the cohort, followed by those aged 30 to 45 years at 29.9 percent. This middle-aged, female-predominant pattern differs from the profiles often seen in settings where injection drug use dominates transmission, and it points instead toward healthcare-associated and community exposures accumulated over years or decades. Because chronic HCV infection progresses slowly, many of these individuals may have acquired the virus long before diagnosis, underscoring the importance of retrospective surveillance data in reconstructing transmission dynamics.

The comorbidity data added another layer of concern. End-stage renal disease was the most frequently reported comorbidity, present in 24.5 percent of cases, followed by diabetes mellitus at 20.9 percent. Both conditions intersect with HCV in clinically meaningful ways. Patients on hemodialysis face elevated risk of nosocomial HCV transmission through contaminated equipment or lapses in infection control, and diabetes has been associated with accelerated liver fibrosis in people chronically infected with the virus. The high proportion of dialysis patients among confirmed cases in Khenchela thus serves as a warning signal about infection control practices in renal care settings, while the diabetes burden suggests that many infected individuals face compounded risks of severe liver and metabolic complications if their hepatitis remains untreated.

When the researchers examined reported potential exposures, two categories stood out. Dental procedures were the most commonly reported, cited by 59.8 percent of cases, and traditional practices accounted for 15.8 percent. Dental care has long been recognized as a plausible route of HCV transmission when instruments are inadequately sterilized, because the virus can survive on surfaces and is efficiently transmitted through blood. The prominence of dental exposure in this cohort, combined with the dialysis connection, led the authors to conclude that enhanced infection control measures are needed particularly in dental and dialysis settings. Traditional practices, which in some communities involve procedures such as cupping or circumcisions performed with non-sterile instruments, represent a more culturally sensitive but equally important target for education and safe-practice interventions.

Algeria has a moderate overall prevalence of HCV, but Khenchela Province has consistently recorded elevated rates, which is precisely why the authors undertook this detailed epidemiological investigation. Their conclusion is direct: HCV incidence in the province exhibits significant geographical clustering concentrated in four primary municipalities, and the predominance of female and middle-aged patients alongside frequent comorbidities highlights key at-risk groups. The study’s practical recommendations follow logically from its data. Targeted screening campaigns should be concentrated in Ouled Rechache, Ain Touila, El Mahmel, and Ensigha, where statistical evidence of clustering is strongest, rather than spread thinly across all municipalities. Simultaneously, infection control audits and training in dental clinics and dialysis units could interrupt the healthcare-associated transmission routes that the exposure data implicate.

The study also demonstrates the value of spatial epidemiology as a tool for regions with limited public health infrastructure. By leveraging routinely collected hospital surveillance data rather than expensive population-based serosurveys, the researchers extracted actionable geographic intelligence at minimal cost. The approach, combining Global Moran’s I with Getis-Ord Gi* hotspot detection, can be replicated in other Algerian provinces and across the broader Middle East and North Africa region, where HCV burden remains substantial and national elimination goals under the World Health Organization’s 2030 targets demand precisely this kind of granular, location-specific evidence. As antiviral therapy for HCV has become shorter, safer, and more effective, the bottleneck has shifted from treatment to finding the infected, and maps like the one now drawn for Khenchela show exactly where the search should begin.

Subject of Research: Spatial epidemiology and hotspot detection of hepatitis C virus incidence in Khenchela Province, Algeria

Article Title: Spatial epidemiology of hepatitis C in Khenchela Province, Algeria: identifying HCV incidence hotspots and implications for regional public health

Article References: Mansouri, M., Brahamia, B., & Mega, N. (2026). Spatial epidemiology of hepatitis C in Khenchela Province, Algeria: identifying HCV incidence hotspots and implications for regional public health. BMC Public Health. https://doi.org/10.1186/s12889-026-29537-w

Image Credits: AI Generated

DOI: 10.1186/s12889-026-29537-w

Keywords: hepatitis C virus, HCV, spatial epidemiology, hotspot detection, Getis-Ord Gi*, Moran's I, Algeria, Khenchela Province, public health surveillance, infection control, dialysis, dental procedures