Prevalence and Factors Associated With Hepatitis B Virus Infection in Tigray Region, Northern Ethiopia.

Hepatitis B virus (HBV) infection is a significant public health concern, particularly in low-income countries. This study investigates the prevalence and associated risk factors of HBV in Alamata district of Tigray region, northern Ethiopia, where the HBV vaccine was introduced in the childhood vaccination programme in 2007. A community-based, cross-sectional study was conducted from December 2019 to June 2020. Data were collected using structured questionnaires and hepatitis B surface antigen (HBsAg) was measured using a rapid diagnostic test. Logistic regression analyses were used to determine the associations between socio-demographic, behavioural and health-related variables and HBV infection. A total of 1853 individuals (54.2% females) were included in this study. The age ranged from 5 to 88 years, and the largest age group was from 5 to 14 years (32.0%). The overall HBV prevalence was 5.3% (95% confidence interval (CI) 4.3-6.3) with significant variability between age groups: 5-14 years 3.7%, 15-24 years 6.8%, 25-34 years 10.1%, 35-44 years 4.4%, 45-54 years 3.9% and 55 years and above 3.4%. Being in the 25-34 years age group (adjusted odds ratio (AOR) 4.1, 95% CI: 1.1-16.2, P= 0.042), reporting multiple sexual partners (AOR 4.0, 95% CI: 1.02-15.4, P= 0.047) and family history of hepatitis B (AOR 3.1, 95% CI: 1.2-8.2, P= 0.024) were independently associated with HBV infection. The prevalence of HBV infection was high in this region, underscoring the necessity for targeted public health strategies aimed at reducing transmission rates. Of note, the HBV prevalence was significantly lower among children born after the introduction of the HBV vaccine.