Hepatitis B Vaccination Impact and the Unmet Need for Antiviral Treatment in Blantyre, Malawi

Abstract

Background Hepatitis B is the leading cause of cirrhosis and liver cancer in sub-Saharan Africa. To reduce hepatitis-associated mortality, antiviral treatment programmes are needed. We estimated prevalence, vaccine impact and need for antiviral treatment in Blantyre, Malawi to inform an effective public health response. Methods We conducted a household study in Blantyre in 2016-2018. We selected individuals from a census using random sampling and estimated age-sex-standardised HBsAg seroprevalence. Impact of infant hepatitis B vaccination, which began in 2002, was estimated by binomial log-linear regression comparing individuals born before and after vaccine implementation. In HBsAg-positive adults, eligibility for antiviral therapy was assessed. Results Of 97,386 censused individuals, 6,073 (median age 18 years; 56.7% female) were sampled. HBsAg seroprevalence was 5.1% (95% CI 4.3–6.1) among adults and 0.3% (0.1–0.6) among children born after vaccine introduction. Estimated vaccine impact was 95.8% (70.3–99.4). Of HBsAg-positive adults, 26% were HIV-positive. Among HIV-negative individuals, 3%, 6% and 9% were eligible for hepatitis B treatment by WHO, European and American hepatology association criteria, respectively. Conclusions Infant HBV vaccination has been highly effective in reducing HBsAg prevalence in urban Malawi. Up to 9% of HBsAg-positive HIV-negative adults are eligible, but have an unmet need, for antiviral therapy.

Prevalence and geo-clinicodemographic factors associated with hepatitis B vaccination among healthcare workers in five developing countries

“…A combined hepatitis B vaccine given at 6, 10, and 14 weeks of age as part of National Immunization Schedule were introduced in Nepal, Senegal, Malawi, Afghanistan, and Haiti in 2002 [31,32], 2002 [33], 2004 [34], 2006 [35], and 2012 [36,37] respectively. However, the birth dose was introduced only in 2014 in Afghanistan [35], while Senegal introduced the monovalent birth-dose vaccine in 2016 [34].…”

“…Yet, the Senegalese government lacks vaccination programme for high risk population such as HCWs [31,32]. Contrary to the WHO recommendations, a birth dose of hepatitis B vaccine is not included or implemented in the present vaccination schedule in Haiti [36] and Malawi [33]. Although immunization of HCWs before they come into contact with patients at all levels is recommended by the Malawian Ministry of Health, there is inconsistent adherence to and enforcement of such recommendations [38].…”

Diagnostic performance of non-invasive fibrosis markers for chronic hepatitis B in sub-Saharan Africa: a Bayesian individual patient data meta-analysis

“…We additionally included unpublished data from three sites (Cape Town, South Africa; Thiès, Senegal; and Dakar, Senegal) and data from one additional study published since the search was conducted from Malawi. 46…”

“…We additionally included unpublished data from three sites (Cape Town, South Africa; Thiès, Senegal; and Dakar, Senegal) and data from one additional study published since the search was conducted from Malawi. 46 Overall, contributing centres reported on 3960 HBsAg positive patients from 12 cohorts in eight countries comprising Burkina Faso, Ethiopia, The Gambia, Malawi, Nigeria, Senegal, South Africa, and Zambia (Figure 1). We excluded 411 ineligible participants who were HIV positive or with unknown HIV status, had received hepatitis B antiviral therapy, had positive anti-HCV or anti-HDV serology or had ALT/AST >5x the upper limit of normal (Figure 2).…”

“…45 Two studies had significant loss to follow up between community diagnosis and evaluation. 38,46 Among 3,549 included participants, median age was 33 years (inter-quartile range (IQR) 28-41) and 60% were male (Table 1 APRI and GPR had the best discriminant performance, with AUROC of 0.81 and 0.82 for cirrhosis and 0.75 and 0.76 for significant fibrosis, respectively. FIB-4 had relatively lower AUROC of 0.77 for cirrhosis and 0.68 for significant fibrosis.…”