My Infectious Disease Follow-Up: What I Learned
After meeting with the Infectious Disease doctor, I left with the understanding that leptospirosis is common after flooding, highly preventable, and very treatable when caught early. This blog summarizes what I learned, researched and answers the key disaster-meeting questions asked.
1. When Should Treatment Start?
Start doxycycline immediately for any suspected case. Do not wait for test results.
First-line treatment:
• Adults: Doxycycline 100 mg twice daily × 7 days
• Children ≥8 years: 2.2 mg/kg twice daily (max 100 mg/dose)
Alternatives for pregnancy and children <8:
• Penicillin G: 1.5 million units IV every 6 hours × 7 days
• Ampicillin: 500–750 mg orally 4 times daily × 7 days
• Amoxicillin: 500 mg orally 3 times daily × 7 days
• Azithromycin: 500 mg day one, then 250 mg daily for 4 days
2. Is There Rapid Testing?
Yes, however, they are most effective when administered a few days after the onset of symptoms.
Rapid tests detect IgM antibodies, which appear after the first few days. The best option in disaster settings is the LEPkit IgM lateral-flow test, which has the highest accuracy, works well in early illness, and is stable in field conditions. If LEPkit is unavailable, Lepto-LF is another strong option from day six onward. More advanced tools, like CRISPR-based molecular assays, exist but are not typically available in field settings. LEPkit remains the most reliable choice for on-site screening.
Best rapid tests for disaster settings:
• IgM lateral-flow tests (LEPkit, Leptocheck-WB, SD Bioline)
Advanced options (if available):
• CRISPR-based RDTs
However, treatment should not be delayed while waiting for the results.
3. Signs & Symptoms (Two Phases)
Early Phase (5–14 days):
• Fever
• Headache
• Chills
• Muscle pain (calves)
• Red eyes
• Nausea/vomiting
• Diarrhea
Severe Phase (Emergency):
• Jaundice
• Trouble breathing
• No urine or dark urine
• Confusion
• Coughing blood
• Weakness
• Swelling
4. Prevention
• Avoid floodwater when possible
• Wear boots, gloves, and protective clothing.
• Cover all cuts
• Wash exposed skin immediately
• Use treated, boiled, or bottled water
• Chemoprophylaxis for responders (Doxycycline 200 mg weekly — not for pregnancy or children <8)
5. Education
The community must know:
• Fever after floodwater exposure needs medical evaluation
• Prompt treatment prevents severe disease
• Children must avoid floodwater
• Wear boots, gloves, and cover all wounds
6. Supportive Care:
• Stay well hydrated
• Control fever (acetaminophen)
• Rest and monitor symptoms
Severe cases: Severe leptospirosis needs hospital care.
The ID MD also suggested the following for personal protection and travel health:
• Complete the Hepatitis A vaccine series
• Receive Typhoid vaccination (Vaccination Information Sheet – CDC attached)
• Check MMR titers, especially with increased travel and airport exposure
• Protect against mosquitoes using clothing spray and skin repellent; permethrin-treated
• Use Pepto-Bismol and keep Azithromycin on hand for traveler’s diarrhea
• Stay hydrated, eat only fully cooked food, drink bottled water, avoid, avoidance of freshwater exposure—should not bathe, swim, wade, particularly in flood-affected areas. Wear an N95 mask when needed, caution around animals, domestic pets.
References
Rajapakse, S., Fernando, N., Dreyfus, A., Smith, C., & Rodrigo, C. (2025). Leptospirosis. Nature Reviews Disease Primers, 11(1), 32.
https://doi.org/10.1038/s41572-025-00614-5
Schafer, I., Galloway, R., & Stoddard, R. (2024). Leptospirosis. In CDC Yellow Book: Health information for international travel. Centers for Disease Control and Prevention.
https://wwwnc.cdc.gov/travel/page/yellowbook-home
Schneider, M. C., Velasco-Hernandez, J., Min, K. D., Corona-Gutierrez, D., Damian, E., Nájera, P., Aldighieri, S., & Hartskeerl, R. (2017). The use of chemoprophylaxis after floods to
reduce the occurrence and impact of leptospirosis outbreaks. International Journal of Environmental Research and Public Health, 14(6), 594.
https://doi.org/10.3390/ijerph14060594
Typhoid Vaccination Sheet – CDC
https://www.cdc.gov/vaccines/hcp/current-vis/typhoid.html