Worldwide, there are more than 200 known serovars of leptospirosis. Dog owners are advised to watch for flulike illnesses in their pets until vaccines are upgraded to include new types of lepto. Today, farmers form the main occupational risk group due to their inevitable exposure to rats and their urine, and to cattle urine. Dairy farmers are being encouraged to take precautions, for their own health. Workers in contact with canal and river water or those who use inland water for recreational activities are potentially at risk, although the risk is judged to be very small.
Simple precautions can significantly reduce the risk.
Immunisation of cattle will reduce the excretion of leptospires in their urine. The rat population should always be reduced, with destruction of their habitats and rat proofing buildings. Those at risk should cover all cuts with waterproof plasters and wear protective clothing or other materials. Immersion in natural waters such as rivers, lakes and canals should be avoided, and individuals should wear footwear and wash or shower after canoeing, windsurfing, swimming or performing other water activites. It is sensible for those in risk groups to carry 'warning cards' to show their doctor if they become ill.