Sero surveillance of leptospirosis among sewer workers in Pune.

Leptospirosis is an important occupational disease affecting people coming in contact with animals and their discharges. The occurrence of infection in ones workplaces is linked to the environment to which the worker is exposed and the adaptability of the organism in that working environment. Rodents usually abound in underground sewers and are carriers of leptospira. The urine of rodents and other animals present in that area is likely to contaminate these sewers. Leptospira are excreted in the urine of infected animals. Thus sewer workers are at a potential risk of leptospirosis. The prevalence of leptospirosis in these workers could thus indirectly predict the presence of the disease in animals in a particular geographical niche. Total seventy-eight sewer workers from 5 different municipal wards in Pune were examined to find out the evidence of past infection with leptospira using microagglutination test (MAT). The prevalence rate was found to be 16.6%. The serovars to which antibodies were detected include autumnalis (38.4%), pyrogenes (23.0%), canicola (15.3%) and pomona (15.3%). Evidence of leptospiral infection was found to be maximum in sewer workers in the areas of the city that were infested with rodents and stray animals.