Hepatitis B epidemiology and cultural practices in Amerindian populations of Amazonia: The Tupí-Mondé and the Xavánte from Brazil

Hepatitis B infection and disease are highly endemic in South America. Prevalences of positivity are particularly high in Amazonia, and among Amerindian peoples in particular. This paper reports the results of a seroepidemiological survey for hepatitis B virus (HBV) carried out among four Amerindian populations from the Brazilian Amazon region: Gavião, Suruí, Zoró and Xavánte. Rates of positivity to HBV serological markers (HBsAg, anti-HBs and/or anti-HBc) are very high for the four groups, ranging from 62.8 to 95.7%. It is argued that the high rates of positivity in the Amerindian groups dealt with in this study, as well as for other Amazonian populations, are related to a complex of cultural practices which enhance the likelihood of HBV transmission (bloodletting, scarification, tattooing and orally processed food, among others). The authors suggest that, due to unique patterns of interaction between sociocultural and environmental factors, HBV infection assumes a specific profile in native Amazonian societies.