[Hepatitis B and D virus infection within Amerindians ethnic groups in the Brazilian Amazon: epidemiological aspects]. / Infecção pelos vírus das hepatites B e D entre grupos indígenas da Amazônia Brasileira: aspectos epidemiológicos.

ABSTRACT

Several studies describe very high prevalence rates of infection and disease of hepatitis B and D within Native American population. This is a review of what has been described among Amerindians of Brazilian Amazon. Some groups show low prevalence rates of HBsAg, whereas, others of the same region reveal high endemic pattern, even among individuals less then 10 years of age. HDV is only found in groups of Amazonas province. Transmission may occur by interfamilial dissemination or sexual contact among young adults. Socio-cultural, genetic, and ecological factors are described as determinants of this unique pattern. Nevertheless, the origin of these two viruses is yet to be disclosed. Amerindians population and their genetic memory are a live experiment, which demands a broad investigation, weighting with modern tools, as molecular biology, the influence of historical, genetic, medical and anthropological factors.