Leptospirosis is an infection caused by leptospira bacteria.
These bacteria can be found in fresh water that has been soiled by animal urine. You may get infected if you consume or come in contact with contaminated water or soil. The infection occurs in warmer climates. Leptospirosis is not spread from person to person, except in very rare cases.
Risk factors include:
- Occupational exposure -- farmers, ranchers, slaughterhouse workers, trappers, veterinarians, loggers, sewer workers, rice field workers, and military personnel
- Recreational activities -- fresh water swimming, canoeing, kayaking, and trail biking in warm areas
- Household exposure -- pet dogs, domesticated livestock, rainwater catchment systems, and infected rodents
Weil disease, a severe form of leptospirosis, is rare in the continental United States. Hawaii has the highest number of cases in the United States.
Symptoms can take 2 to 30 days (average 10 days) to develop, and may include:
- Dry cough
- Muscle pain
- Nausea, vomiting, and diarrhea
- Shaking chills
Less common symptoms include:
Exams and Tests
The blood is tested for antibodies to the bacteria. During some phases of the illness, the bacteria themselves can be detected using polymerase chain reaction (PCR) testing.
Other tests that may be done:
Medicines to treat leptospirosis include:
Complicated or serious cases may need supportive care. You may need treatment in a hospital intensive care unit (ICU).
The outlook is generally good. However, a complicated case can be fatal if it is not treated promptly.
Complications may include:
- Jarisch-Herxheimer reaction when penicillin is given
- Severe bleeding
When to Contact a Medical Professional
Contact your health care provider if you have any symptoms of, or risk factors for, leptospirosis.
Avoid areas of stagnant water or floodwater, especially in tropical climates. If you are exposed to a high risk area, take precaution to avoid infection. Wear protective clothing, shoes, or boots when near water or soil contaminated with animal urine. You can take doxycycline to decrease the risk.
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
Galloway RL, Stoddard RA, Schafer IJ. Leptospirosis. CDC Yellow Book 2020: Health Information for the International Traveler. Centers for Disease Control and Prevention. wwwnc.cdc.gov/travel/page/yellowbook-home. Updated July 18, 2019. Accessed October 7, 2020.
Haake DA, Levett PN. Leptospira species (leptospirosis). In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 239.
Zaki S, Shieh W-J. Leptospirosis. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 307.