Seroprevalence of hepatitis B virus and hepatitis C virus in Monte Negro in the Brazilian western Amazon region.
OBJECTIVE
This study was carried out in Monte Negro (state of Rondônia), a village in the Brazilian western Amazon region, where a University of São Paulo Medical School program for medical student training in rural assistance took place. It aimed to determine the prevalence of hepatitis B virus and hepatitis C virus, to investigate risk factors for infection, and to evaluate the State immunization program against hepatitis B virus in the region.


METHODS
The study is a cross-sectional seroprevalence survey, comprising 267 volunteers who answered a comprehensive questionnaire and had blood samples collected, which were analyzed in São Paulo for the presence of antibodies against hepatitis B virus (Hbs Ag, anti-Hbs, and anti-Hbc) and hepatitis C virus using commercial kits. Data were stored in a specific data bank, and the association between seropositivity and potential risk factors was analyzed by means of uni-, bi-, and multi-variate analysis, considering +/- 5%.


RESULTS
The seroprevalence of hepatitis B virus was 61.79% and of hepatitis C virus was 0.38%. Statistical analysis on the data bank showed that the prevalence of hepatitis B virus rose significantly with age, especially after adolescence. Infection was higher in those coming from outside the state of Rondônia. Exposure to vaccination against hepatitis B virus was higher in younger individuals and in those who were born in Rondônia.


CONCLUSIONS
Monte Negro is a highly endemic region for hepatitis B virus but not for hepatitis C virus. Our results also provide indirect evidence indicating a significant improvement in the immunization program in Rondônia in recent years.
El Khouri
Marcelo
M
Laboratory of Infectious Disease and Central Laboratory Division, Hospital das Clínicas, Faculty of Medicine, University of São Paulo, São Paulo, SP, Brazil.
Duarte
Leandro Savoy
LS
Ribeiro
Rafael Bernadon
RB
da Silva
Luis Fernando Ferraz
LF
Camargo
Luis Marcelo Aranha
LM
dos Santos
Vera Aparecida
VA
Burattini
Marcelo Nascimento
MN
Corbett
Carlos Eduardo Pereira
CE
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay; D004812:Epidemiologic Methods; D005260:Female; D016174:Hepacivirus / Q000276:immunology*; D006508:Hepatitis Antibodies / Q000097:blood*; D006509:Hepatitis B / Q000097:blood / Q000453:epidemiology* / Q000276:immunology; D006510:Hepatitis B Antibodies / Q000097:blood; D017325:Hepatitis B Vaccines / Q000276:immunology; D006515:Hepatitis B virus / Q000276:immunology*; D006526:Hepatitis C / Q000097:blood / Q000453:epidemiology* / Q000276:immunology; D018937:Hepatitis C Antibodies / Q000097:blood; D006801:Humans; D017589:Immunization Programs / Q000592:standards*; D008297:Male; D008875:Middle Aged; D015397:Program Evaluation; D012424:Rural Population; D012959:Socioeconomic Factors
D015415:Biomarkers; D006508:Hepatitis Antibodies; D006510:Hepatitis B Antibodies; D017325:Hepatitis B Vaccines; D018937:Hepatitis C Antibodies