Prevalence and clinical significance of occult hepatitis B infection in The Gambia, West Africa.

OBI is endemic and an independent risk factor of advanced liver disease in The Gambia, West Africa. This implies that HBsAg-negative people with liver disease should be systematically screened for OBI. Moreover, the impact of infant hepatitis B immunization to prevent end-stage liver disease might be higher than previous estimates based solely on HBsAg-positivity.