Health Alert: Screwworm in Nicaragua (July 7, 2025)
Location: Throughout Nicaragua
Event: Nicaragua’s Institute for Agricultural Protection and Health (IPSA) identified a total of 124 cases of human infection of the New World Screwworm (NWS) in the last year. NWS is a flesh-eating parasite caused by the Screwworm fly, which is similar in appearance to the common housefly.
How Screwworms Infest: Female Screwworm flies lay their eggs in the living tissue of warm-blooded hosts, mainly in open, untreated wounds. Within hours, the eggs hatch into small larvae that feed on the surrounding tissue. Screwworm flies predominantly affect farm animals, including cattle, pigs, and horses, but can affect dogs, cats, and occasionally humans.
When to Seek Medical Attention:
- If you notice unusual wounds or lesions that worsen or contain maggots.
- If you experience severe pain, redness, swelling, or infection of any wound.
Actions To Take:
- Visit the CDC page on New World Screwworm for additional information about the disease, including symptoms, prevention, and treatment.
- Visit the IPSA page for local Spanish-language information on New World Screwworm.
- Refer to our list of local medical providers.
- Check with your medical provider if you have any questions regarding upcoming travel.
- Check with your travel insurance provider about options should you fall ill while overseas.
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