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This fact sheet answers frequently asked questions about Leptospirosis.

Leptospirosis is a bacterial disease that affects humans and animals.

The basics

What is leptospirosis?

In people, it can cause a wide range of symptoms. Some infected people may have no symptoms at all. Untreated infection could cause kidney damage, meningitis, liver failure, and breathing problems. In rare cases, it may lead to death. 

How do people get leptospirosis?

People get this disease through contact with the urine of an infected animal. Outbreaks of leptospirosis are usually caused by touching or swallowing contaminated water or soil. The bacteria can also enter the body through skin or mucous membranes. This risk increases for scratched or cut skin. The disease rarely spreads from person to person.

Where is leptospirosis found?

Leptospirosis occurs worldwide but is most common in temperate or tropical climates. You can find the bacteria in cattle, pigs, horses, dogs, rodents, and wild animals. People who work outdoors or with animals are at a significant risk. Leptospirosis is also associated with contaminated bodies of water. The incidence is also increasing among urban children.


What are the symptoms of leptospirosis?

People become sick between 2 days to 4 weeks after exposure. In humans, leptospirosis can cause a wide range of symptoms, including:

  • High fever
  • Headache
  • Chills
  • Muscle aches
  • Vomiting
  • Jaundice (yellow skin and eyes)
  • Red eyes
  • Abdominal pain
  • Diarrhea
  • Rash

Some infected people may have no symptoms at all.

Leptospirosis occurs in two phases. The first phase can include:

  • fever
  • chills
  • headache
  • muscle aches
  • conjunctivitis
  • vomiting
  • diarrhea

The person may recover for a time but then become ill again. The second phase is more severe. Phase two, known as Weil's disease, may cause liver or kidney failure. People in phase two may also develop meningitis.

The illness can last from a few days to 3 weeks or longer. Without treatment, recovery may take several months.


How can people prevent leptospirosis?

You can reduce the risk of getting leptospirosis by not swimming or wading in contaminated water. Wear protective clothing or footwear if you face exposure to contaminated water.

If your dog has leptospirosis, you should:

  • Keep your dog in your house or yard to prevent the spread of disease
  • Do not let your dog urinate in or near ponds, pools, or puddles
  • Always wash your hands after touching anything that might have your dog's urine on it
  • If you are cleaning where there is dog urine, use an anti-bacterial cleaning solution or a solution of 1 part bleach in 10 parts water
  • Make sure that your dog takes all of its medication


How is leptospirosis treated?

Health care provider treat leptospirosis with antibiotics. People who think they might have leptospirosis should contact a health care provider.

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