Three-year Dhaka study tracks hepatitis C genotypes and viral load

Hepatitis C virus genotype 3 accounted for 90.35% of the genotypes identified in a three-year study of 435 hepatitis C virus-positive patients in Dhaka, Bangladesh. Researchers used real-time polymerase chain reaction to examine genotype distribution and viral load from 2023 through 2025. Genotype 3 remained predominant throughout the observation period, but the overall distribution changed significantly across the three years, while the viral-load measurements showed a decreasing trend that did not reach the level of statistical significance reported by the authors.

The study identified five HCV genotypes among the 435 patients. In addition to genotype 3, the researchers detected genotype 1a in 5.29% of participants, genotype 1b in 3.91%, and genotypes 2 and 6 in 0.23% each. Genotype 3 was therefore the most frequently observed genotype, followed by 1a and 1b. Patients aged 31–50 years constituted the largest age group. The recorded distribution between males and females was nearly even, with 50.35% and 49.65%, respectively. These percentages characterize the genotypes and participants included in the study rather than establishing the prevalence or distribution of HCV infection in Dhaka or across Bangladesh.

Viral load varied in relation to both sex and genotype. Multivariate linear regression estimated viral load to be approximately four times higher in males than in females, with a reported coefficient of β = 0.60 and p < 0.0001. This was an association measured by the model, not evidence that sex caused the difference. When results were divided into viral-load categories, genotype 3 had a higher overall viral load than genotypes 1a and 1b. Genotype 1b, however, had higher proportions of patients in the high- and medium-viral-load categories than either genotype 1a or genotype 3, a difference reported at p = 0.02. The findings thus distinguished the continued numerical predominance of genotype 3 from the way viral-load categories were distributed among the different genotypes.

Year-by-year analysis found a significant change in genotype distribution from 2023 to 2025, reported at p = 0.04. Genotype 3 remained the leading genotype during the study period, followed by genotypes 1a and 1b, but the composition was not unchanged: genotype 1b was not detected in 2025. The researchers also observed a decreasing trend in viral load over the three years, although the reported value was p = 0.06. The supplied findings do not identify the cause of either the temporal shift in genotype distribution or the decreasing viral-load trend, nor do they provide a basis for attributing the absence of genotype 1b in 2025 to any specific transmission, treatment, or surveillance factor.

The results provide a measured description of viral characteristics among 435 HCV-positive patients in Dhaka over 2023–2025. The authors identify genotype and viral load as variables with clinical and epidemiological implications for hepatitis C management and describe the findings as a basis for further research into viral behavior across time and between sexes. Because the research focused on the included patients and their measured genotypes and viral loads, it does not by itself establish population-level prevalence, explain the observed trends, or demonstrate differences in disease progression, treatment response, or transmission. Its clearest findings are that genotype 3 dominated the sample throughout the three years, genotype distributions shifted measurably, and viral load was associated with sex in the regression analysis.

Subject of Research: Temporal distribution of hepatitis C virus genotypes and viral load among 435 patients in Dhaka, Bangladesh, from 2023 to 2025

Article Title: Temporal trends of the genotype and viral load of hepatitis C virus among patients in Dhaka, Bangladesh

Article References: Haque, S., Hossain, M., Nila, N. N., Nazneen, S., Kabir, M. M., & Ahmed, M. (2026). Temporal trends of the genotype and viral load of hepatitis C virus among patients in Dhaka, Bangladesh. BMC Infectious Diseases. https://doi.org/10.1186/s12879-026-14267-6

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14267-6

Keywords: hepatitis C, HCV genotype 3, viral load, real-time PCR, genotype distribution, temporal trends, sex differences, Dhaka, Bangladesh, viral epidemiology, Temporal, trends