Leptospiral exposure in Detroit rodent control workers.

Antibody levels to L. icterohemorrhagiae of rodent control workers and two control groups were compared with antibodies against five other leptospiral serotypes carried predominantly by species other than rats. Rodent control workers contact urban rats, 77 per cent of which are carriers of leptospiral organisms. Rodent control workers had higher antibody levels against L. icterohemorrhagiae than control groups (OR 4.37, 99 per cent CI = 3.0, 6.3 and OR 11.08, 99 per cent CI = 5.6, 22). Antibodies against the other five serotypes were almost non-existent in the study group.