Leptospira interrogans serovars hardjo and pomona: causes of infections in dairy cows and humans in Florida.

Leptospirosis was diagnosed in 11 milkers on 3 dairy farms in a Florida county. Serologic test results identified Leptospira interrogans serovar hardjo as the infecting organism in milkers and cows on one farm, and hardjo was isolated from two cows. On the second farm, serovars hardjo and pomona were implicated serologically in the cows and milkers, and pomona was isolated from two milkers. On the third farm, hardjo infection was identified by serologic tests in one milker, and hardjo was isolated from another.This was the first isolation of hardjo from a human being reported in the United States. Leptospiral infection is an occupational hazard for dairy milkers in some areas of the United States. Thus, the authors recommend that preventive measures should be taken. These measures should include boots and other protective clothing and protection from urine spray for the eyes and nose.