Definition of Leptospirosis:

Leptospirosis is a rare and severe bacterial infection that occurs when people are exposed to certain environments.

Causes, incidence, and risk factors:

Leptospirosis is caused by exposure to several types of the Leptospira bacteria, which can be found in fresh water that has been contaminated by animal urine. It occurs in warmer climates.

It is not spread from person to person, except in vary rare cases when it is transmitted through breast milk or from a mother to her unborn child.

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

Leptospirosis is rare in the continental United States. Hawaii has the highest number of cases in the United States.

Symptoms:

Symptoms can take 2 - 26 days (average 10 days) to develop, and may include:

• Dry cough
• Fever
• Headache
• Muscle pain
• Nausea, vomiting, and diarrhea
• Shaking chills

Less common symptoms include:

• Abdominal pain
• Abnormal lung sounds
• Bone pain
• Conjunctivitis
• Enlarged lymph glands
• Enlarged spleen or liver
• Joint aches
• Muscle rigidity
• Muscle tenderness
• Skin rash
• Sore throat

Signs and tests:

The blood is tested for antibodies to the bacteria.

Other tests that may be done:

• Complete blood count (CBC)
• Creatine kinase
• Liver enzymes
• Urinalysis

Treatment:

Medications to treat leptospirosis include:

• Ampicillin
• Ceftriaxone
• Doxycycline
• Penicillin

Complicated or serious cases may need supportive care or treatment in a hospital intensive care unit (ICU).

Expectations (prognosis):

The outlook is generally good. However, a complicated case can be life-threatening if it is not treated promptly.

Complications:

• Jarisch-Herxheimer reaction when penicillin is given
• Meningitis
• Severe bleeding

Calling your health care provider:

Contact your health care provider if you have any symptoms of, or risk factors for, leptospirosis.

Prevention:

Avoid areas of stagnant water, especially in tropical climates. If you are exposed to a high risk area, taking doxycycline or amoxicillin may decrease your risk of developing this disease.