U.S. Confirms Travel-Related Human Screwworm Case in Maryland
Health officials confirmed the first U.S. case of New World screwworm infection this year. The patient, a traveler returning from Central America—either El Salvador or Guatemala—is being treated in Maryland.
What Is the Screwworm Parasite?
The New World screwworm is a parasitic fly whose larvae infest open wounds of warm-blooded animals and, in rare cases, humans. The larvae consume living tissue, leading to severe injury or even death if not treated. While the parasite was eradicated in the U.S. decades ago, outbreaks have re-emerged in parts of Central America and southern Mexico.
Risk Levels and Livestock Concerns
Officials stressed that the risk to the general public remains very low. However, the greater threat lies in livestock populations. An uncontrolled outbreak could cause billions of dollars in economic losses, with estimates for Texas alone reaching $1.8 billion in damages.
U.S. Response and Preventive Steps
The U.S. Department of Agriculture announced plans to build a sterile fly production facility in Texas to help prevent the parasite’s spread. This approach, which involves releasing sterilized male flies, was used successfully in the past to eradicate screwworm in North America. No animal cases have been detected so far in the U.S.
