Leptospirosis (Weil's Disease)

What is leptospirosis?

Leptospirosis is a bacterial infection that can spread to humans from animals and is caused by a type of bacteria called Leptospira. Cattle, dogs, pigs and rats can carry leptospirosis. You can catch it when soil or water contaminated with animal urine gets into your eyes, mouth and nose or into your skin via cuts or scratches. It can also be passed on by direct contact with animal blood or body fluids.

Where is it found?

Leptospirosis is found all over the world, including the UK. It is most common in places with regular heavy rainfall and flooding. Higher risk areas include Brazil, the Caribbean, China, India, Malaysia, the Pacific islands, Seychelles, Sri Lanka, Thailand and Viet Nam.

In 2010, there were 39 cases of Leptospirosis reported in the UK, with 17 infections caught abroad. Most of these travellers had been to South East Asia.

What is my risk?

Any activities involving contact with fresh water increase your risk; for example swimming, canoeing, rafting and fresh-water fishing. Your risk is higher after lots of rain, as the earth gets soaked and soil contaminated with leptospirosis bacteria floods into rivers and lakes. In 2000, an outbreak was reported in Eco-Challenge tourists in Borneo, Malaysia. Events during this Challenge included sailing, swimming, kayaking and canoeing in rivers after heavy rainfall.  

Any work involving contact with soil, animals and their blood or body fluids also puts you at risk e.g. abattoir workers, butchers, farmers, sewage workers, soldiers and vets.

What are the symptoms?

Symptoms can appear from two to 30 days after you come into contact with the bacteria. Most people (about 90%) have a mild flu like illness or no symptoms at all. Unfortunately, the other ten percent can develop a serious, potentially fatal illness. Older people, very young children and anyone with significant health problems are much more likely to develop severe problems.

Early symptoms include:

  • Fever, chills and muscle ache.
  • Headache.
  • Nausea and loss of appetite.
  • Stomach pain. 

Symptoms then usually disappear, but can return one to three days later. A rash may then also develop. Complications of severe illness include brain infection, inflamed heart muscle and liver or kidney failure, which can be fatal.  

How can I reduce my risk?                                  

  • Avoid contact with animals, fresh water and soil as much as possible.
  • Cover cuts and grazes with waterproof plasters. Wash wounds carefully if you think you have been in contact with fresh water, animal fluids or soil.
  • Follow good food and water hygiene advice.
  • If you are camping, keep your site clean and rubbish free, to avoid attracting rats and other rodents.
  • Wash your hands thoroughly after any contact with animals.
  • Wear protective clothing like goggles, masks waterproof gloves and boots, if your job increases risk of exposure.

Is there a vaccine?

There is no vaccine. Antibiotics can be prescribed to prevent infection. However, this is usually only in exceptional circumstances, when people cannot avoid contact with rodents, soil, water or sewage, often during work in high risk regions.

Can it be treated?

Leptospirosis can be treated with antibiotics. However, if you develop a severe form, you usually require urgent hospital treatment; often in a high dependency ward or intensive care unit and you may need kidney dialysis.

After recovery, you will be immune to the strain of leptospirosis you were infected with, but are unlikely to be protected against different types. Therefore, it is important you take care not to become infected again.



The National Travel Health Network and Centre (NaTHNaC) is commissioned by the Health Protection Agency to provide health information for both healthcare professionals and travellers. Information is compiled by the NaTHNaC clinical and scientific team, and updated regularly. Further advice on health risks and disease outbreaks is available at www.nathnac.org.

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