Health authorities in the United States have confirmed the first human case of infestation by a flesh-eating parasite known as New World screwworm myiasis.
The Department of Health and Human Services disclosed on Monday that the infection was detected in a patient who had recently returned from El Salvador.
Confirmation of the case was made on August 4.
NWS myiasis is caused by the larvae of parasitic flies—commonly referred to as maggots—that feed on living tissue.
The condition is known to primarily affect livestock, but officials have noted that the risk to the general public in the U.S. remains “very low.”
The Centers for Disease Control and Prevention (CDC) partnered with Maryland’s health department to investigate the case.
HHS spokesperson Andrew Nixon stated, “This represents the first human case of travel-associated NWS myiasis from an outbreak-affected country identified in the U.S.”
The parasite, which aggressively targets living tissue, is typically found in South America and the Caribbean. Despite containment efforts, the infestation has now been recorded in every Central American country, including Mexico.
According to the CDC, humans can become infected, particularly those with open wounds. Travelers to outbreak regions and individuals in rural areas with close contact to livestock are considered more vulnerable.
The U.S. Department of Agriculture (USDA)’s Animal and Plant Health Inspection Service is collaborating with agricultural agencies, the State Department, and the Food and Agriculture Organization of the United Nations to manage the situation.
“When NWS fly larvae (maggots) burrow into the flesh of a living animal, they cause serious, often deadly damage to the animal,” the USDA warned. “NWS can infest livestock, pets, wildlife, occasionally birds, and in rare cases, people.”
The USDA also cautioned that an outbreak among livestock could pose significant economic risks, potentially threatening over $100 billion in cattle and livestock-related industries.
