The occupational hazards of leptospirosis in the meat industry.

The sera from 1215 meat inspectors and 1248 meat workers were examined for the presence of agglutinating titres of 1:24 or greater to the serovars of Leptospira interrogans known to be endemic in New Zealand. Although 10 percent of meat inspectors and 6.2 percent of meat workers were seropositive, only 9.5 percent of meat inspectors and 4.1 percent of meat workers had titres compatible with occupational exposure to domestic stock. The subgroup of meat workers with the highest prevalence of agglutinins (10.4 percent) were those working on the slaughter floor, and the inspection and processing of pigs were shown to be the most important risk factors. More than 50 percent of those with a history of medically confirmed leptospirosis in the past ten years still had detectable titres. Although the results of this survey demonstrate that leptospirosis is a definite occupational hazard in the meat industry, the risk is threefold less than for dairy farm workers and pig farmers.