Viral Hepatitis: The African Experience

Abstract

It is estimated that chronic viral hepatitis affects nearly 550 million people worldwide. While previous studies report approximately 350 million individuals are infected with hepatitis B virus (HBV), 185 million with hepatitis C virus (HCV) and 15 million with hepatitis delta virus [1, 2], recent updates from the World Health Organization (WHO) have revised estimates placing worldwide burden of chronic HBV at 257 million individuals. Viral hepatitis causes substantial mortality, globally accounting for more than 1 million deaths each year. Chronic viral infection is the primary cause of hepatocellular carcinoma (HCC), which is one of the most common cancers in developing countries and the second cause of cancer-related mortality worldwide [3].

Summary Table of Landmark Literature

Study title and authors	Study design	Summary results	Main limitations
Lemoine M, et al. Lancet Glob Health. 2016;4(8):e559–67	Population-based prospective study from December 7, 2011 to January 24, 2014 evaluating the effectiveness of point of care HBsAg testing among individuals in randomly selected communites in western Gambia and potential blood donors in the central hospital of Banjul.	• Among the community-based cohort that underwent testing, HBsAg prevalence was 8.8%. • Among the cohort of potential blood donors, HBsAg prevalence was 13.0%. • HBsAg prevalence was significantly higher in men compared to women (10.5% vs. 7.6%, p = 0.004)	• Single country study among select populations may not be generalizable to populations in other African countries. • Overall test acceptance rates were 68.9% among the community-based cohort and 81.4% among the blood donor-based cohort
Kirk GD, et al. Hepatology 2004;39:211–9	The Gambia Liver Cancer Study (GLCS) was conducted in conjunction with The Gambia Hepatitis Intervention Study, an international collaborative project designed to evaluate the efficacy of phased introduction of hepatitis B vaccine into The Gambia’s national immunization program in preventing chronic HBV infection, chronic liver disease, and HCC from September 1997 through January 2001	• 216 incidence cases of HCC and 408 controls were recruited into the study. • HBsAg prevalence was 61% among incidence HCC patients and 165 among non-HCC controls. • Overall, 57% of HCC cases were attributed to chronic HBV infection	• Single country study among select populations may not be generalizable to populations in other African countries • Relatively small sample size and may not reflect larger population-based HBV prevalence
Lemoine M, et al. J Hepatol 2015;62:469–76	Review paper highlighting the burden of viral hepatitis in Africa and discussion on potential strategies to achieve eradication among this high prevalence region	• According to WHO, HBV infection affects more than 5% of the local population in Sub-Saharan Africa and more than 8% in West Africa, reaching up to 15% in some areas • WHO estimates that very few countries have implemented an HBV birth dose vaccine strategy and that only 23% of children born in the African continent benefit from the early birth dose • Nosocomial transmission is another major route of viral hepatitis transmission in Africa. WHO estimates that 24% of blood donations in low-income countries are not systematically screened for HBV	• Review paper is limited by the lack of epidemiological data in many parts of the African continent. • Lack of epidemiological studies prevents an accurate assessment of HBV prevalence in many regions of Africa.