Changes in the prevalence of hepatitis B and C viral infections in Sindh province, Pakistan: Findings from two sero-surveys in 2007 and 2019.

Pakistan harbours a large burden of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection. We utilised repeat sero-surveys to assess progress achieved towards hepatitis elimination in Pakistan. Multilevel logistic regression evaluated the change in HBV infection (HBV surface antigen (HBsAg)-positive) prevalence and HCV exposure (HCV antibody (HCV-Ab)-positive) prevalence between two sero-surveys from 2007 and 2019 for Sindh province and associated risk factors. Adjusted odds ratios (aORs) were estimated and population-attributable fractions (PAF) for modifiable risk factors for HCV exposure. The 2007 and 2019 surveys included 8855 and 6672 individuals. HBsAg prevalence decreased from 2.6% (95% confidence intervals (95% CI): 2.2-2.9) in 2007 to 1.1% (95% CI: 0.8-1.3) in 2019, while HCV-Ab prevalence increased from 5.1% (95% CI: 4.6%-5.5%) to 6.2% (95% CI: 5.6%-6.8%). The age and gender-adjusted HBsAg prevalence decreased by 80% (aOR = 0.2, 95% CI: 0.1-0.4) among children and 60% (aOR = 0.4, 95% CI: 0.3-0.6) among adults over 2007-2019, while HCV-Ab prevalence decreased by 60% (aOR = 0.4, 95%CI:0.2-0.7) in children and increased by 40% (aOR = 1.4, 95% CI: 1.2-1.7) in adults. HCV-Ab prevalence was lower in adults with secondary (aOR = 0.6, 95% CI: 0.5-0.8) and higher (aOR = 0.5, 95%CI:0.3-0.8) education compared to illiterates and higher among adults reporting blood transfusion (aOR = 1.7, 95% CI: 1.2-2.4), family history of hepatitis (aOR = 2.5, 95% CI: 1.9-3.3), past year medical injection (aOR = 2.1, 95% CI: 1.6-2.7), being tattooed (aOR = 1.4, 95% CI: 1.0-1.9) and shaved by traditional barber (aOR = 1.2, 95% CI: 1.0-1.5). Modifiable risk factors accounted for 45% of HCV exposure, with medical injection(s) accounting for 38% (95%CI,25.7-48.4%). Overall HCV has increased over 2007-2019 in Sindh province, while HBV prevalence has decreased. Medical injections should be an important focus of prevention activities.