Leptospirosis & Weil’s Disease

Leptospirosis is a bacterial infection carried in rat’s urine which may contaminate water in lakes, rivers, etc. The bacteria does not survive long in dry conditions or salt water. The risk of infection is greater in stagnant or slow-moving water but cases have occurred in swift moving streams and lowland rivers. There is an enhanced risk where flash floods have washed out rat runs.

The infection is caught by direct contact with the urine or polluted environment. Bacteria enter through skin abrasions or via eyes, nose or mouth.

The usual incubation is 2 to 12 days. Usually a ‘flu’ like illness occurs which resolves in 2-3 weeks. There may be fever, severe headache, pains in the back and calf and prostration. A few cases develop Jaundice, when the condition is known as Weil’s disease.

Each year an average of 3 canoeists contract Leptospirosis. It is very rare and it’s deterioration into Weil’s disease even more rare. Weil’s disease is however, a serious ilness and must be swiftly diagnosed and treated. Death may occur in about 15% of Weil’s disease cases (i.e. jaundiced patients) but death without jaundice is virtually unknown. Antibiotics during the first few days help in limiting infection. Many cases recover without specific treatment.

If you think you may have the infection go to your doctor and explain that their may be a risk of leptospirosis. The diagnosis is by clinical suspicion. Blood tests can rarely confirm the illness in time to affect treatment but are needed to subsequently confirm it.

Further information is available from The Leptospirosis Reference Unit, Public Health Laboratory, County Hospital, Hereford, HR1 2ER