Leptospirosis (including Weil disease)
Cause
Various spirochaetes of the genus Leptospira.
Transmission
Infection occurs through contact between the skin (particularly skin abrasions) or mucous membranes and water, wet soil or vegetation contaminated by the urine of infected animals, notably rats. Occasionally, infection may result from direct contact with urine or tissues of infected animals or from consumption of food contaminated by the urine of infected rats.
Nature of the disease
Leptospiral infections take many different clinical forms, usually with sudden onset of fever, headache, myalgia, chills, conjunctival suffusion and skin rash. The disease may progress to meningitis, haemolytic anaemia, jaundice, haemorrhagic manifestations and other complications, including hepatorenal failure.
Geographical distribution
Worldwide. Most common in tropical countries.
Risk for travellers
Low for most travellers. There is an occupational risk for farmers engaged in paddy rice and sugar cane production. Visitors to rural areas and in contact with water in canals, lakes and rivers may be exposed to infection. There is increased risk after recent floods. The risk may be greater for those who practise canoeing, kayaking or other activities in water. Outbreaks associated with eco-sports activities have occurred.
Prophylaxis
Doxycycline may be used for prophylaxis if exposure is likely. Vaccine against local strains is available for workers where the disease is an occupational hazard, but it is not commercially available in most countries.
Precautions
Avoid swimming or wading in potentially contaminated waters including canals, ponds, rivers, streams and swamps. Avoid all direct or indirect contact with rodents.