Prevalence of leptospirosis in various risk groups.

Two hundred and twenty seven patients were included in the study. The test group included 55 patients of pyrexia of unknown origin (PUO), 42 veterinary workers, 38 hepatitis patients and 25 village farmers. The control group comprised of 27 Syphilis controls and 40 healthy controls. Of the total study entrants, 186 were tested for Leptospira antibodies by IgM ELISA and 41 by microscopic agglutination test (MAT). ELISA results of 45 patients were further tested by MAT for comparative evaluation. Out of 160 patients of the test group 56(35.0%) were positive for Leptospira antibodies. The positivity was 18(32.73%) amongst PUO patients, 15(35.71%) of the farm workers, 15(39.47%) of hepatitis patients and 8(32.0%) farmers. Leptospira antibodies were not detected in any of the controls. The antibody positivity was seen in 33(32.04%) of the 103 urban patients and 23(40.35%) of 57 rural patients. Out of 56 Leptospira cases, in 39(69.64%) history of animal contact was present. The common clinical features in these patients included fever in 51(91.07%), myalgia 48(85.71%), headache 42(75.0%), Anorexia 31(55.35%), Jaundice 24(42.86%) and nausea/vomiting in 21(37.5%). Of the 45 ELISA results compared with that of MAT, there was 86.67% agreement between the tests.