Background and aim: Hepatitis B is a major public health problem in Vietnam; however, estimates of the prevalence of hepatitis B virus (HBV) and hepatitis delta virus (HDV), and risk factors in rural Vietnam are limited. The aim of this study was to determine HBV and HDV prevalence, and identify risk factors for HBV infection.
Methods: A cross-sectional seroprevalence study was undertaken in two rural districts in Thai Binh province. The study population was randomly selected using multistage sampling. Demographic and behavioral risk information and serological samples were obtained from 837 participants.
Results: Mean age was 42.3 years +/- 15.8 (range, 16-82 years), and 50.8% were female. Prevalence of anti-HBV core antibody (anti-HBc) and hepatitis B virus surface antigen (HBsAg) was 68.2% and 19.0%, respectively, and hepatitis B e antigen HBeAg was detected in 16.4% of the HBsAg-positive group. Prevalence of HDV was 1.3% in the HBsAg-positive group. Factors associated with HBV infection (anti-HBc or HBsAg positive) were age 60 years or older (OR, 3.82; 95% CI, 1.35-10.80; P = 0.01), residence in Vu Thu district (OR, 3.00; 95% CI, 2.16-4.17; P < 0.0001), hospital admission (OR, 2.34; 95% CI, 1.33-4.13; P = 0.003) and history of acupuncture (OR, 2.01; 95% CI, 1.29-3.13; P = 0.002). Household contact with a person with liver disease (OR, 2.13; 95% CI, 1.29-3.52; P = 0.003), reuse of syringes (OR, 1.81; 95% CI, 1.25-2.62; P = 0.002) and sharing of razors (OR, 1.69; 95% CI, 1.03-2.79; P = 0.04) were independent predictors of HBsAg positivity. Alanine aminotransferase (ALT) level was elevated (>40 IU/L) in 43% of the HBsAg-positive group; proportion elevated was higher in HBeAg-positive (65%) compared with HBeAg-negative (39%) individuals in this group (P = 0.02).
Conclusion: Hepatitis B virus infection is highly endemic in rural Vietnam. Poor infection control activities in health-care settings contribute to high HBV prevalence in this region. Universal HBV infant vaccination and improved infection control procedures are required for improved HBV control in Vietnam.