First Human Case of Flesh-Eating Screwworm Parasite Confirmed in the US

The rare parasite, which can turn into a devastating epidemic, was discovered in a human for the first time in Florida.

The FDA recently confirmed the screwworm parasite, Cochliomyia hominivorax, on a human for the first time ever in the United States. Until now, the parasite was known to infect livestock and other animals in South and Central America, but this is the first known case of a human infestation. The occurrence was reported in Florida, presumably through the bite of a screwworm fly.

What You Should Know

• The parasite, Cochliomyia hominivorax, can burrow into the living flesh of mammals, including humans, to lay eggs.
• The state of Florida is prone to infestations because the climate is ideal for the fly that spreads the parasite.
• Infested animals and humans are not usually able to detect the parasite until tissue damage and myiasis (invasion of the living tissues for egg laying) have occurred.
• Infested areas need to be treated with ivermectin, a drug that is also used to treat demodectic mange and other mange infections in dogs and cats.
• The public is encouraged by health and regulatory agencies to report any suspicious cases of infestation in livestock or humans.