Seroprevalence and risk factors of hepatitis B virus infection in tribal population of Himalayan district Lahaul and Spiti, India.

Hepatitis B virus (HBV) infection is an important health issue across the world. With 4% to 7% prevalence of HBV, India is designated as an intermediate endemic country. However, HBV prevalence is significantly high in some pockets of the country, especially among tribal populations. HBV prevalence and associated risk factors in residents of far-flung two Himalayan valleys, Lahaul and Spiti of Himachal Pradesh (HP), were estimated. This was a community-based cross-sectional study. Blood samples were collected and tested for the presence of hepatitis B surface antigen (HBsAg) using ELISA. Data was collected in a predesigned semi-structured format. Univariate and multivariate analyses of risk factors were done using software SPSS 25. Samples from 1,327 individuals residing in 32 villages were tested, of these 141 (10.6%) were found positive for HBsAg. High prevalence (17.2%) of HBV was recorded in Spiti valley but not in Lahaul valley (3.1%). Both sexes were equally affected. Positivity was higher in adults than in children. High risk sexual behavior (OR = 2.0; 95% CI: 1.1-3.6), having an HBV positive person in the family (OR = 2.4; 95% CI: 1.4-4.3), being a student (OR: 11.2; 95% CI 3.9-32.1) and preacher (OR = 9.0; 95% CI: 3.6-22.4) were the most prominent risk factors associated with HBsAg positivity. Mass immunization for HBV along with information, education, communication and behavior change communication for curtailing risk behavior for avoiding risk factors is essential in the area.