Leptospira hebdomadis associated with an outbreak of illness in workers on a farm in North Yorkshire

Four cases of illness attributed to Leptospira hebdomadis occurred on a cattle farm in North Yorkshire. The clinical features were a febrile illness that resembled influenza; in one case there was a lymphocytic meningitis. This infection is probably more common than is recognised at present, and prevention of further cases may be possible if diagnosed promptly.