Prevalence of hepatitis B and D virus infection in a district of Mato Grosso, bordering Amazonas and Rondônia states

Abstract

Introduction: Brazil's western Amazon basin has the highest prevalence of hepatitis B virus (HBV) infection in the country. Coinfection with hepatitis D virus (HDV) is also endemic. To estimate the prevalence of HBV and HDV markers in a population inhabiting the northwest portion of Mato Grosso state in the western Amazon. Methods: We performed a cross-sectional study of the seroprevalence of antibodies against HBV core antigen (anti-HBc) in the Três Fronteiras District northwest of Mato Grosso. Anti-HBc-positive subjects were tested for HBV surface antigen (HBsAg). Those positive for this marker were tested for HDV antibodies. Anti-HBc-negative participants were tested for anti-HBsAg. All tests were performed by EIA. Results: A total of 623 individuals in the community were assessed; the majority (67.6%) were male, with a mean age of 30.8 ± 15.4 years. Two hundred and fourteen individuals (34.3%) were anti-HBc-positive, and 47 (7.5%) were HBsAg carriers. Only one individual was anti-HDV-positive. Among the 409 individuals without HBV infection, 18.3% were anti-HBsAg-positive. There was no association between HBV infection and known risk factors. Conclusions: The study area had intermediate-to-high endemicity for HBV infection, but a low prevalence of HDV. Our serological results suggesting low vaccinationinduced protection indicate a need for reinforced immunization programs in the populations of northwest Mato Grosso.

Prevalence, Risk Factors and Vaccine Response against Hepatitis B in People Aged 50 Years or Older

“…On the other hand, high rates of exposure to HBV in older individuals can be observed in different regions of Brazil. For example, in the midwest, an investigation carried out in a district in the interior of Mato Grosso estimated the prevalence of anti-HBc at 46.7% (95% CI: 32.8%–55.2%) in 71 individuals aged equal to or greater than 50 years [ 25 ]. In the north region, in Tocantins, a study carried out with individuals residing in a small municipality and with Amerindian tribes in the eastern Amazon determined a rate of exposure to HBV of 34.1% (95% CI: 25.2%–44.3%) in 91 older adults (>60 years) [ 26 ].…”

Tendências e distribuição espacial da hepatite D no Norte do Brasil, 2009-2018: um estudo ecológico

“…4,5 No Brasil, casos fora da região Norte são reportados esporadicamente, sendo mais comuns em estados fronteiriços à região. 6,7 Baixa escolaridade, falta de acesso à saúde e ausência de sintomas são alguns fatores que retardam o diagnóstico e o cuidado para populações vulneráveis. 4,6,8,9 Apesar das dificuldades regionais, esforços têm sido feitos para controlar o agravo, assegurando-se a oferta de vacinas e medicamentos às comunidades mais remotas.…”