Seroprevalence of HBsAg and its risk factors among pregnant women in Jimma, Southwest Ethiopia

Abstract

Abstract Background: Vertical transmission from mother to baby is an important route of transmission for hepatitis B virus infection. Neonates who contract hepatitis B will have an almost 90 % risk of developing chronic HBsAg carriage and chronic liver disease. Neonatal immunization interrupts this vertical transmission. Objective: To determine the sero-prevalence of HBsAg among pregnant women and to identify potential risk factors associated with the infection. Methods: A cross-sectional study was conducted from October, 2002 to March, 2003 in a total of 493 pregnant women attending Mother and Child Health clinics of Jimma university specialized hospital and its Training Health Centers. Serum was collected from each woman and tested for the presence of HBsAg using Bioline Strip, which is a qualitative, solid phase two site sandwich immunoassay (Pacific Biotech, Thailand). A pre-structured questionnaire was used to collect socio-demographic data and to find out possible risk factors. Results: The overall prevalence of HBsAg was 3.7% ranging from 1.4% to 6.4%. It was highest in Jimma and lowest in Shebe town. The socio-demographic status of the study population shows that high proportion of HBsAg positivity was among the illiterate (61%), those whose income <500 Birr / month (88.9%) and among the Oromo ethnic subgroup (83%). Pregnant women who experience abortion had a higher prevalence of HBsAg (7.3%). The odds of having HBsAg was more than twice with those with history of abortion than with other risk factors. When pregnant women of Jimma town were separately analyzed, dental procedure, cesarean section and tattooing are associated with HBsAg positivity, unlike other towns. Conclusion: The prevalence of HBsAg carrier state in the study area was significant enough to start routine antenatal screening for HBsAg. Except for abortion, known risk factors included in the study were not associated with Hepatitis B virus infection. The main route of HBV transmission in Jimma and its neighboring towns could be either through sexual contact or from mother to child. Further studies are required to confirm these modes of transmission. [Ethiop.J.Health Dev. 2005;19(1):45-50]