Prevalence of hepatitis B infection among the accessible tribes

Hepatitis B infection is found to be high in tribal population worldwide. There was no information about the status of hepatitis B infection among the primitive tribes of Andaman and Nicobar Islands. Hence, the Centre carried out a sero-survey among the accessible tribes of these islands viz. Great Andamanese, Onges, Nicobarese and Shompens. The Jarawas and Sentinelese were not accessible when the study was carried out. The sampling details are given in table 1

Fig 1. Prevalence of HBsAg and anti-HBs among primitive tribes of Andaman and Nicobar Islands

Sera samples were collected from different tribes and analyzed for Hepatitis B surface antigen (HBsAg) and antibodies to HBsAg (anti-HBs). Findings of the survey showed that HBV infection is highly endemic among the tribes of these islands with HBsAg rates ranging between 3.7% in Great Andamanese to 37.8% in Shompens (Fig 1) .  The rates of HBsAg reported from the tribes of these islands are the highest reported rates in India.