[Serological survey on arbovirus infection in residents of an ecological reserve].
OBJECTIVE
Serological inquires conducted in the Ribeira Valley, S. Paulo State, Brazil, showed an intense circulation of pathogenic arboviruses in the region. The goal was to verify the prevalence of arboviral infections in people living at the local ecological, and its potential association with these population' individual and familiar characteristics.


METHODS
The study was carried out among 182 persons of 58 families to identify the presence of antibodies to the following viruses: Rocio (ROC), Ilheus (ILH), Eastern equine encephalitis virus (EEE), Western equine encephalitis virus (WEE), Venezuelan equine encephalitis virus (VEE) and St. Louis encephalitis virus (SLE). Inhibition hemagglutination test and plaque reduction neutralization test were the laboratory assays of choice. MAC-ELISA was used to identify IgM antibodies to ROC, ILH and EEE viruses.


RESULTS
The prevalence of antibodies was 26.9% (21. 4% to alphavirus and 12.6% to flavivirus). There were no antibodies to WEE virus. IgM antibodies were not observed suggesting no recent infection in study population. Among the characteristics investigated, age, occupation, place of birth and the habit of going into the forest were shown to be statistically associated with arboviral infection (p<0.05).


CONCLUSIONS
It was observed an intense circulation of pathogenic arboviruses, especially VEE. It seems the habit of going into the forest is the most important factor to this population exposure to the mosquito vectors of arboviruses. The results suggest the need of further investigation to clarify the role of birds as arbovirus infection amplificators indoors.
Departamento de Prática de Saúde Pública da Faculdade de Saúde Pública da Universidade de São Paulo, São Paulo, SP, Brasil. nicolina@usp.br
N S
NS
Romano-Lieber
L B
LB
Iversson
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000914:Antibodies, Viral / Q000302:isolation & purification; D001102:Arbovirus Infections / Q000175:diagnosis / Q000453:epidemiology*; D001103:Arboviruses / Q000276:immunology / Q000302:isolation & purification; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D009033:Culicidae / Q000276:immunology; D005260:Female; D006801:Humans; D007223:Infant; D007303:Insect Vectors / Q000276:immunology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D014197:Trees
D000914:Antibodies, Viral