Seroprevalence of hepatitis B virus infection and associated factors among prison inmates in state of Mato Grosso do Sul, Brazil.

INTRODUCTION: This study aimed to estimate the prevalence of HBV infection and associated factors among prison inmates in Campo Grande, MS. METHODS: A total of 408 individuals were interviewed regarding sociodemographic characteristics, associated factors and HBV vaccination using a standardized questionnaire. Blood samples were collected from all participants and serological markers for HBV were detected by enzyme-linked immunosorbent assay. Hepatitis B surface antigen (HBsAg) and/or antibodies against hepatitis B core antigen (anti-HBc) positive samples were tested for HBV-DNA by polymerase chain reaction. RESULTS: The overall prevalence of HBV infection was 17.9% (95%CI: 14.4-22.0). The HBsAg carrier rate was 0.5%; 56 (13.7%) individuals had been infected and developed natural immunity and 15 (3.7%) were positive for anti-HBc only. Ninety eight (24%) prisoners had only anti-HBs, suggesting that they had low vaccine coverage. An occult HBV infection rate of 0% was verified among anti-HBc-positive individuals. Multivariate analysis of associated factors showed that age > 35 years-old, low schooling level and illicit drug use are significantly associated with HBV infection. CONCLUSIONS: Analysis of the data showed HBV infection prevalence similar or slightly lower than that reported in other of Brazilian prisons. Independent predictors of HBV infection in this population include older age, low schooling level and illicit drug use.

Seroprevalence of hepatitis B virus infection and associated factors among prison inmates in state of Mato Grosso do Sul, Brazil / Soroprevalência e fatores associados à infecção pelo vírus da hepatite B em população encarcerada no estado do Mato Grosso do Sul, Brasil

INTRODUCTION: This study aimed to estimate the prevalence of HBV infection and associated factors among prison inmates in Campo Grande, MS. METHODS: A total of 408 individuals were interviewed regarding sociodemographic characteristics, associated factors and HBV vaccination using a standardized questionnaire. Blood samples were collected from all participants and serological markers for HBV were detected by enzyme-linked immunosorbent assay. Hepatitis B surface antigen (HBsAg) and/or antibodies against hepatitis B core antigen (anti-HBc) positive samples were tested for HBV-DNA by polymerase chain reaction. RESULTS: The overall prevalence of HBV infection was 17.9 percent (95 percentCI: 14.4-22.0). The HBsAg carrier rate was 0.5 percent; 56 (13.7 percent) individuals had been infected and developed natural immunity and 15 (3.7 percent) were positive for anti-HBc only. Ninety eight (24 percent) prisoners had only anti-HBs, suggesting that they had low vaccine coverage. An occult HBV infection rate of 0 percent was verified among anti-HBc-positive individuals. Multivariate analysis of associated factors showed that age > 35 years-old, low schooling level and illicit drug use are significantly associated with HBV infection. CONCLUSIONS: Analysis of the data showed HBV infection prevalence similar or slightly lower than that reported in other of Brazilian prisons. Independent predictors of HBV infection in this population include older age, low schooling level and illicit drug use.

INTRODUÇÃO: O presente estudo teve como objetivo investigar a prevalência da infecção pelo HBV e os fatores associados a esta infecção em população encarcerada de Campo Grande, MS. MÉTODOS: Quatrocentos e oito encarcerados, provenientes das populações encarceradas do Instituto Penal de Campo Grande, Presídio de Segurança Máxima e Presídio Feminino Irmã Irma Zorzi, foram entrevistados sobre dados sociodemográficos e fatores associados à infecção pelo HBV. A seguir foram coletadas amostras sanguíneas para detecção dos marcadores HBsAg, anti-HBs e anti-HBc total por ensaio imunoenzimático. O HBV-DNA foi detectado pela reação em cadeia da polimerase nas amostras HBsAg e anti-HBc reagentes. RESULTADOS: A prevalência global para infecção pelo HBV foi de 17,9 por cento (IC 95 por cento: 14,4-22,0), 13,7 por cento (56/408) para o anti-HBc total associado ao anti-HBs e em 15 (3,7 por cento) indivíduos foi detectada a presença do anti-HBc isolado. HBsAg foi encontrado em 0,5 por cento (2/408) dos indivíduos estudados, evidenciando uma baixa prevalência de casos crônicos. Em 24 por cento (98/408) dos indivíduos, verificou-se positividade isolada ao marcador anti-HBs, sugerindo baixa cobertura vacinal ao HBV. Após análise multivariada, ter idade maior que 35 anos, baixo nível de escolaridade e uso de droga ilícita permaneceram associados significativamente à infecção pelo HBV. CONCLUSÕES: A prevalência da infecção pelo HBV encontrada foi similar às reportadas em outros estudos conduzidos em populações encarceradas do Brasil. Os fatores de risco associados a esta infecção foram aumento da idade, baixo nível de escolaridade e uso de droga ilícita.