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What is leptospirosis?

Leptospirosis is a disease caused by bacteria (germs). It can affect humans and animals.  In people, it may cause a wide range of symptoms. However, some infected people may have no symptoms at all. Untreated infection could cause kidney damage, meningitis (inflammation of the lining around the brain and spinal cord), 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 water or soil that has been contaminated with the urine of infected animals. The bacteria can also enter the body through skin or mucous membranes (eyes, nose, or mouth), especially if the skin is broken from a cut or scratch. The disease rarely spreads from person to person.

Where is leptospirosis found?

Leptospirosis occurs worldwide but is most common in temperate or tropical climates. The bacteria have been found in cattle, pigs, horses, dogs, rodents, and wild animals. People who work outdoors or with animals (i.e. farmers, sewer workers, veterinarians, fish workers, dairy farmers, or military personnel) are at a significant risk. Leptospirosis has also been associated with swimming, wading, and whitewater rafting in contaminated lakes and rivers. 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, and diarrhea.  The person may recover for a time but then become ill again.  The second phase is more severe.  In the second phase, people may experience kidney or liver failure or develop meningitis.  This phase is called Weil's disease.

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

How is leptospirosis treated?

Leptospirosis is treated with antibiotics. People who think they might have leptospirosis should contact a health care provider immediately.

How can leptospirosis be prevented in people?

The risk of getting leptospirosis can be greatly reduced by not swimming or wading in water that is contaminated with animal urine. Protective clothing or footwear should be worn by those exposed to contaminated water or soil because of their job or recreational activities.

If your dog has been diagnosed with leptospirosis, you should:

  • Keep your dog in your house or yard to prevent 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 medicine.
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