Assessment of mother-to-child HBV transmission at the prenatal consultation in Vientiane, Laos

Abstract

Chronic infection with hepatitis B virus (HBV) remains highly endemic in Laos, mainly related to mother to child transmission. Despite the introduction of the vaccination against HBV in the Expanded Programme on Immunization in 2001 and the administration of a vaccine birth dose as part of a 3-dose schedule since 2004, infant immunization coverage remains inadequate because most mothers are not aware of the risks. A survey was conducted in early 2013 in Vientiane capital among women who undergo serologic screening for hepatitis B at the prenatal consultation, to assess their knowledge and risk factors of HBV infection. It included the administration of a standardized questionnaire divided into four parts (socio-demographic data, knowledge about hepatitis B, risk factors and immunization status) and a screening test for the HBV surface antigen (HBsAg). A total of 200 pregnant women were recruited consecutively in Mahosot hospital. They were aged 14-39 years (mean 27 ± 4.76 years), civil servants (37%) or housewives (33.5%) with a secondary or higher education level (80%). Most were multiparous (68.5%) and attended antenatal care in the third trimester of pregnancy (61%). Sixteen (8%) tested HBsAg positive. The HBsAg seroprevalence was higher in the 26-30 years age group, among women above the primary school education level and women practicing the profession of shopkeeper or civil servant, but these differences were not significant. Hepatitis B was known by a small majority (53%) but 26% could name the routes of transmission, 28% considered it as a serious illness and 24.5% were aware of the HBV vaccine. No risk factor for blood or sexual exposure to HBVinfection was significantly linked to the HBsAg carriage. In this sample of pregnant women mostly urban, educated and multiparous with access to a central hospital, the high rate of HBV infection and the low level of knowledge about the risk of mother-to-child HBV transmission reveals a major gap in information and advice that should be provided during prenatal visits. A large scale program of health education focused on the prevention of vertical transmission of HBV should be implemented, parallel to the extension of HBV vaccine coverage including a birth dose for the Lao children.