Arthropod-borne encephalitis virus in northeastern South America. Part I. A serological survey of northeastern Surinam

ABSTRACT

Sera from 492 adults and children were collected in northeastern Surinam in January 1960 and examined in haemagglutination-inhibition and neutralization tests for the presence of antibodies to 11 arboviruses. Neutralization tests results with sera from the 76 adults bled in the coastal towns (Paramaribo, Lelydrop, and Marienburg) and 216 adults bled in settlements in the forested interior were compared. Neutralizing antibody rates for Mayaro, yellow fever, and Ilheus viruses were higher in the forested interior and there higher in males than in females. Antibody rates for V.E.E. virus were also higher in the interior, but in both environments the rates for the sexes were about equal. Antibody rates for dengue type 2 and St Louis viruses were simliar for the two environments and difference between the sexes were not considered significant. Cache Valley virus antibody rates were about the same in the town and the forest, but in both environments were higher in males. Only nine persons immune to E.E.E. virus were encountered, all living in the interior. No antibodies were found against W.E.E. and Manzanilla viruses. Test with Trinidad group C virus, 34053-1, related to Caraparu, provide evidence of group C immune reactors among inhabitants of the interior. Neutralization test results with sera from 93 children in forested environments and 107 who lived away from the forest were in accordance with the results obtained with the sera from adults. In the village of Matta, in the white sand zone, 32 of 34 adults and 10 of 14 children had V.E.E. neutralizing antibodies in their sera. Limited tests with 32 sera from the hinterland Amerindians collected in 1959 gave results similar to those obtained in the 1960 survey (Summary)