Leptospirosis Risk in Outdoor Activities

Leptospirosis is a disease caused by bacteria. These bacteria are carried in the urine of infected animals. If an infected animal urinates in a body of fresh water (e.g., lake, river, stream) or soil, the disease can live there for weeks to months.
Leptospirosis exists all over the world, but it is more likely to be found in tropical climates. The risk is higher after a hurricane, flood or heavy rain.

How People Get It

Photo: Two people walking though a stream.

People may come into close contact with fresh water or damp soil when they participate in outdoor activities. For example, they might accidentally swallow some water while swimming in a lake or have an open cut that gets dirty during a muddy hike.
Participating in activities such as kayaking, canoeing, hiking, climbing, and other similar types of outdoor activities can increase the risk of leptospirosis infection. These activities – sometimes called "adventure racing" – often involve entering bodies of fresh water and/or contact with soil for long periods of time.
If the water or soil was contaminated with leptospirosis bacteria, that person could be at risk for developing the disease. The bacteria can enter the body through the eyes, nose, mouth or broken skin.

Symptoms

Symptoms may appear anywhere from two days to four weeks after exposure to the bacteria. Many cases result in mild, flu-like symptoms or no symptoms at all. When symptoms occur they can include:

Chills
Vomiting
Diarrhea
Stomach pain
Rash

More serious cases, however, can cause life-threatening infections in the kidneys, liver, brain, lungs and heart.

How You Can Reduce Your Risk

If your outdoor activities will involve fresh water or damp soil, you can take steps to lower your chances of getting leptospirosis.

Research the area in which you will be spending time outdoors, and be aware of potential risks—especially if you're going somewhere new on vacation. (See CDC's Travelers' Health Yellow Book.)
Wear protective clothing and shoes.
Wait until cuts or scrapes are healed before going into fresh water or damp soil. (If you can't wait, cover cuts and scrapes with watertight bandages.)
Try to avoid going under water or swallowing water in lakes, rivers or swamps.

If you develop symptoms of the disease, be sure to see a doctor. This is especially important if you have recently been in fresh water, damp soil or mud. The doctor can give you testing and treatment.
Head out and enjoy the great outdoors this summer, and take it all in—just not leptospirosis!