ABSTRACT Children have an increased likelihood of becoming carriers of the chronic hepatitis B virus. A total of 1,381 children and adolescents were assessed in five municipalities of Maranhao State, Brazil, for detection of anti-HBc, HBsAg and anti-HBs serologic markers and sociodemographic and behavioral features. Among those who were HBsAg negative and anti-HBc negative, the proportion of anti-HBs positives was calculated after the individuals had completed the vaccination schedule. The robust variance of the Poisson’s regression model was used in order to have adjusted tables and calculate the prevalence ratio. Multivariate analysis was performed to identify the factors associated with the prevalence of anti-HBc with or without HBsAg and the vaccine response. It was observed that 163 children were anti-HBc positive and nine individuals were HBsAg positive. The factors associated with the infection were: municipality of residence (residing in Morros municipality or Humberto de Campos municipality), residence in a rural area, aged between 13 and 15 years old, and illicit drug use. The percentage of individuals who were anti-HBc negative and received all three doses of the vaccine was 48.5%. Among these, only 276 (38.9%) had antibodies at protective concentrations. In an adjusted analysis, Morros municipality presented an increased positivity of vaccine response (p < 0.001), and the age ranging between 6 and 10 years old presented a reduced frequency of response. This study reveals a high prevalence of current and past HBV infection within the targeted age group which, in addition to the low vaccination coverage and serological responses, raises concerns about the management of prevention measures, especially the quality of vaccination in these locations.

Resumo Introdução: A vacinação é a medida mais efetiva na prevenção da transmissão do vírus da hepatite B (HBV). O portador de doença renal crônica (DRC) em diálise apresenta maior risco de se contaminar com este vírus e não tem a mesma resposta vacinal quando comparada com indivíduos sem uremia. Objetivos: Avaliar os resultados da vacina para o HBV e identificar fatores associados à resposta, em portadores de DRC em hemodiálise. Metodologia: Foram avaliados indivíduos com HBsAg e anti-HBc negativos, que estavam sob hemodiálise em duas unidades de São Luís, Maranhão e que haviam sido submetidos ao esquema completo de vacinação para o HBV. Foram distribuídos em dois grupos: anti-HBs < 10mUI/mL e anti-HBs ≥ 10mUI/mL e comparados quanto à idade, gênero, presença de diabetes mellitus (DM), tempo em diálise e status do anti-HCV. Análise de regressão logística foi realizada para identificar fatores independentemente associados à resposta vacinal. Anti-HBs ≥ 10mUI/mL(OR = 5.239 IC:1.279-21.459, p = 0.021) Conclusões: A taxa de resposta vacinal ao HBV em portadores de DRC em diálise foi de 70% e a ausência do anti-HCV foi associada à soroconversão do anti-HBs, sugerindo que a infecção pelo vírus da hepatite C pode ser um fator que diminui a resposta da vacina para o HBV em indivíduos portadores de DRC em diálise.

Abstract Introduction: Vaccination is the most effective tool in preventing transmission of Hepatitis B Virus (HBV). The patient with chronic kidney disease (CKD) on dialysis appear to be at greater risk of becoming infected with this virus and does not show the same vaccine response when compared to patients without uremia. Objectives: To evaluate the results related to the HBV vaccine and identify factors associated with the response in patients with CKD on hemodialysis. Methods: Individuals with HBsAG and negative anti-HBC, under hemodialysis were assessed in two units of São Luis, Maranhão and were undergone full vaccination schedule for HBV. They were divided in groups: anti-HBs10 mUI/mL and compared as to age, gender, presence of diabetes mellitus (DM), time on dialysis and anti-HCV status. Logistic regression analysis was performed to identify factors independently associated with the vaccine response. p10mUI/Ml (or = 5.239 IC: 1.279-21.459, p = 0.021). Conclusion: The rate of vaccine response to HBV in patients with CKD on dialysis was 70% and the lack of anti-HCV infection was associated with seroconversion of anti-HBs suggesting that infection by the hepatitis C virus may be a factor that decreases the response of the HBV vaccine in dialysis CKD patients.