Leptospirosis is an illness caused by the bacteria Leptospira. You can get leptospirosis after getting water or soil contaminated by animal pee (urine) in your nose, your mouth, your eyes or a break in your skin. Leptospirosis can cause flu-like symptoms that can worsen into Weil’s syndrome, a life-threatening illness, in a small number of people.


Symptoms of leptospirosis include high fever, red eyes, headache, muscle aches, abdominal pain, yellow skin or eyes and more.
Symptoms of leptospirosis start two days to four weeks after exposure. Your symptoms may go away and come back as more severe illness.

What is leptospirosis?

Leptospirosis is an illness caused by an infection with the bacteria Leptospira. You can get infected with Leptospira through abrasions or cuts in your skin, or through your eyes, nose or mouth.

Leptospirosis is a zoonotic disease, which means it’s transmitted between animals and humans. You can get infected through:

  • Direct contact with pee (urine) or reproductive fluids from infected animals.
  • Contact with contaminated water or soil.
  • Eating or drinking contaminated food or water.


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Who is most at risk for leptospirosis?

You can get leptospirosis no matter where you live, but it’s most common in tropical areas and warmer climates with lots of rainfall each year. You’re at an increased risk for leptospirosis if you live in or travel to these areas, including:

  • Oceania (Australia, New Zealand and the Pacific Islands).
  • The Caribbean.
  • Parts of sub-Saharan Africa.
  • Parts of Latin America.
  • South and Southeast Asia.

Outbreaks of leptospirosis have occurred in the U.S. after flooding in Hawaii, Florida and Puerto Rico. Recreational freshwater activities, especially ones that put you in contact with contaminated water for long periods of time, put you at increased risk. This includes activities that put your head underwater or cause you to swallow water (for instance, white water rafting, swimming and boating). Your risk is even greater after heavy rainfall or flooding.

How common is leptospirosis in humans?

It’s estimated that more than 1 million people worldwide get leptospirosis each year. Almost 60,000 of those die from it.


What are the phases of leptospirosis?

Leptospirosis consists of two phases: the leptospiremic (acute) phase and the immune (delayed) phase. You may have mild symptoms or no symptoms in the leptospiremic phase. Some people develop severe symptoms in the immune phase.

Leptospiremic phase

During the leptospirosis phase (also called the septicemic phase) you may experience a sudden onset of flu-like symptoms. This usually starts within two to 14 days after a Leptospira infection. It lasts between three and 10 days.

In this phase, bacteria are in your bloodstream and moving to your organs. Blood tests will show signs of infection.

Immune phase

In the immune phase, Leptospira bacteria has moved from your blood to your organs. The bacteria is most concentrated in your kidneys, which make pee (urine). Urine tests will show signs of the bacteria and you’ll have antibodies to Leptospira in your blood.

A small number of people will get very sick with Weil’s syndrome in this phase. Weil’s syndrome causes internal bleeding, kidney damage and severe yellowing of your skin and eyes (jaundice).

Symptoms and Causes

What are the symptoms of leptospirosis in humans?

Some people have flu-like symptoms of leptospirosis and some have no symptoms at all. In severe cases of leptospirosis, you have symptoms of internal bleeding and organ damage.

In acute leptospirosis, symptoms come on suddenly, including:

Severe leptospirosis (Weil’s syndrome) symptoms may start three to 10 days later, including:


What causes leptospirosis?

The bacteria Leptospira causes leptospirosis. Bacteria get into your body through your mouth, nose or eyes or through breaks in your skin. They travel through your blood to your organs, collecting in your kidneys (the organ that “cleans” your blood).

Your kidneys get rid of unnecessary or toxic matter in your pee (urine). Bacteria from your kidneys leaves your body in your pee, which can spread leptospirosis to other people or animals.

How does leptospirosis spread?

Leptospirosis is usually spread to humans from animal pee containing the bacteria Leptospira. Almost any mammal (like rats, dogs, horses, pigs or cows) can get leptospirosis. They may have few or no symptoms of illness.

Animals with leptospirosis can contaminate water or dirt (soil), which spreads the bacteria to other animals or humans. You can get leptospirosis from:

  • Directly touching pee or other body fluids from an animal with leptospirosis.
  • Getting contaminated water or soil in your eyes, nose or mouth or in a break in your skin.

A lot of people can get leptospirosis at once (an outbreak) after heavy rains and flooding. The floodwaters wash into rivers, lakes and canals, bringing bacteria with them.

Leptospirosis is rarely contagious from one person to another.

Diagnosis and Tests

How is leptospirosis diagnosed?

Your healthcare provider diagnoses leptospirosis with a physical exam, blood tests and urine tests. Your provider will ask you about your symptoms, your travel history and whether you could’ve been in contact with anything contaminated. If you’re very sick, you may have a chest X-ray or CT scan.

What tests will be done to diagnose leptospirosis?

  • Blood or urine tests. Your provider will get a blood sample from your arm with a small needle or you’ll pee in a cup for a urine sample. A lab will test the samples for signs of Leptospira.
  • Imaging. If you are showing signs of severe leptospirosis, your provider may use a chest X-ray, CT scan or other imaging. They’ll use a machine to take pictures of the inside of your body to look for damage to your organs.

Management and Treatment

How is leptospirosis treated?

Your healthcare provider will treat leptospirosis with antibiotics. If you have a mild case, they may have you keep an eye on your symptoms to see if you get better without treatment.

If you have severe leptospirosis, you’ll stay in the hospital. Your provider will give you antibiotics directly through an IV (a needle connected to a tube that brings medicine to your blood). Depending on which of your organs are affected, you may need additional medications or procedures.

What medications and procedures are used to treat leptospirosis?

  • Antibiotics. Types of antibiotics that treat leptospirosis include doxycycline, amoxicillin, ampicillin, penicillin-G and ceftriaxone. Your provider will decide which to use based on how sick you are and your medical history.
  • Mechanical ventilation.If your lungs are infected with bacteria, you may have a hard time breathing and need the help of a machine to breathe for you. Your provider will give you medication to keep you asleep while you’re connected to the machine.
  • Plasmapheresis. Also called plasma exchange, plasmapheresis might help you if you’re at risk for organ damage from leptospirosis. During this procedure, your provider removes your blood using a tube attached to a vein. A machine separates your plasma from your blood and replaces it with a plasma substitute. Your blood is then returned to your body through another tube.

How do I manage the symptoms of leptospirosis?

For mild symptoms, your healthcare provider can recommend treatments to help you feel better. Over-the-counter medications like ibuprofen (Advil®, Motrin®), naproxen (Aleve®) or acetaminophen (Tylenol®) can help aches and pains and reduce your fever.


How can I prevent leptospirosis?

A vaccine for leptospirosis isn’t available in the U.S. The best way to prevent leptospirosis is by not swimming or wading in water that might have animal pee in it. This includes floodwaters. Other ways you can reduce your risk include:

  • Taking preventative medication. If you’re traveling and at high risk for leptospirosis, ask your provider about taking medication to keep from getting sick (prophylaxis).
  • Avoiding animals that could have leptospirosis.
  • Wearing protective clothing and shoes if you work with or around animals.
  • Wearing protective shoes and clothing if you have to be in contact with water or soil that might be contaminated with bacteria.
  • Avoiding water sports and swimming in lakes and rivers after floods.
  • Drinking only treated water. Don’t drink water from lakes, rivers and canals without boiling it first.
  • Wearing gloves if you have to touch dead animals. Don’t touch them with your bare hands and wash your hands thoroughly afterwards.
  • Covering open cuts or wounds with waterproof dressing.

Outlook / Prognosis

What can I expect if I have leptospirosis?

Most cases of leptospirosis are mild and don’t need treatment. Your healthcare provider will still keep a close eye on your symptoms.

If your symptoms worsen or you have new symptoms, don’t hesitate to contact your provider. Go to the ER if you have any symptoms of Weil’s syndrome.

How long does leptospirosis last?

Mild cases of leptospirosis last a few days to a few weeks. If you have severe leptospirosis, you can be in the hospital for about two weeks. It can take several months to fully recover from severe leptospirosis.

When can I go back to work/school?

Leptospirosis is rarely contagious from person to person, so you can go back to work or school as soon as you feel better.

Can humans survive leptospirosis?

Yes, you can survive leptospirosis. Most cases of leptospirosis have no symptoms or have very mild symptoms that go away on their own.

Only about 1% of people with leptospirosis get severely ill with Weil’s syndrome. Weil’s syndrome is often deadly if not treated or if you delay treatment. But if treated promptly, it’s very likely you’ll recover.

Living With

How do I take care of myself with leptospirosis?

If you’ve been diagnosed with leptospirosis, keep an eye on your symptoms. Contact your healthcare provider if any of them worsen or if you have new symptoms.

When should I see my healthcare provider about leptospirosis?

Contact your healthcare provider if you’ve been in water or soil that could’ve been contaminated with bacteria and you have any symptoms of leptospirosis.

When should I go to ER?

Go to the nearest ER if you have symptoms of severe leptospirosis, including:

  • Coughing up blood.
  • Chest pain.
  • Trouble breathing.
  • Yellow skin or eyes.
  • Black, tarry poop (stool).
  • Blood in your pee.
  • Decrease in the amount you pee.
  • Rash-like red spots on your skin.

What questions should I ask my doctor?

  • How did I get sick?
  • When should I follow up with you?
  • What symptoms should I contact you about?
  • When should I go to the ER?

A note from Cleveland Clinic

Leptospirosis is an uncommon disease that usually causes mild symptoms but can cause serious illness in a small number of people. It’s important to know if your job or hobbies put you at risk, but you don’t need to hang up your kayak or work boots just yet. Knowing your risks, taking precautions and recognizing symptoms can help keep you healthy and safe wherever life takes you.

Medically Reviewed

Last reviewed on 08/16/2022.

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