Symptoms and Clinical Features
- Fever, headache, chills, muscle aches, vomiting, nausea, diarrhea, abdominal pain, cough, conjunctival suffusion, jaundice, and sometimes rash.
- Incubation period: 5-14 days with a range of 2-30 days.
- Untreated patients could develop kidney damage, meningitis, liver failure, respiratory distress, and in some cases, may die.
- Leptospires are long, thin, motile spirochetes
- Spreads in the urine of animal hosts, survives for weeks to months in fresh water and wet soil in warm areas
- Leptospiral serovars and species can vary by region
- Classified into over 300 pathogenic serovars based on antigenic properties. However, antigenic properties are not a predictor of species designation.
- Early treatment may decrease the severity and duration of disease.
- In patients with a high clinical suspicion of leptospirosis, initiating antibiotic treatment as soon as possible without waiting for laboratory results is recommended.
- For patients with mild symptoms, doxycycline is the drug of choice (100 mg orally, twice daily), if not contraindicated. Other options include azithromycin (500 mg orally, once daily), ampicillin (500-750 mg orally, every 6 hours), amoxicillin (500 mg orally, every 6 hours).
- For patients with severe disease, IV penicillin is the drug of choice (1.5 MU IV, every 6 hours), and ceftriaxone (1 g IV, every 24 hours) can be equally effective.
Leptospirosis is a nationally notifiable condition. The case report form is available in English and Spanish as a fillable PDF that can be completed electronically or can be printed and done by hand. Completed forms can be emailed, faxed, or mailed to CDC.
Leptospirosis Fact Sheets available in English and Spanish.
Incidence and Trends
- An estimated 1 million cases occur globally each year, resulting in nearly 60,000 deaths.
- In the United States, about 50% of annual cases are reported from Puerto Rico.
- Cases of leptospirosis can increase after hurricanes or flooding when people may have to wade through contaminated water or use it for drinking or bathing.
- Occurring mostly in tropical and subtropical climates, leptospirosis is among the leading zoonotic disease causes of illness worldwide. Health experts believe leptospirosis is underdiagnosed and underreported; true numbers are likely higher.
Find out more about laboratory submissions by visiting Bacterial Special Pathogens Branch Laboratory Submissions.