Seroprevalence of and risk factors for leptospirosis in the City of Manaus, State of Amazonas, Brazil.

INTRODUCTION: Leptospirosis is caused by a bacterium of the genus Leptospira. This study aimed at investigating the seroprevalence of and risk factors for leptospirosis in humans in Manaus, State of Amazonas.

METHODS: Interviews were performed, and 1,000 blood serum samples were examined using a microscopic agglutination test.

RESULTS: Forty-three cases were positive; there were 10 serotypes, with coagglutination in 8 cases. The most frequently occurring serotypes were Icterohaemorrhagiae (20.7%), Cynopteri (20.7%), Australis (18.8%), and Copenhageni (16.9%), and the Midwest (54.7%) and South (23.8%) had the most cases; these areas lack basic sanitation.

CONCLUSIONS: Disease occurrence might be reduced through improved basic infrastructural conditions.