An individual in Maryland has been confirmed to have an an infection with the flesh-eating New World screwworm parasite — the primary human case of the an infection in america for the reason that parasite was eradicated within the U.S. over 60 years in the past, in line with the U.S. Division of Well being and Human Providers (HHS).
The Maryland affected person had returned to the U.States. after touring to El Salvador, HHS spokesperson Andrew G. Nixon advised Reuters in an e mail, and the Facilities for Illness Management and Prevention (CDC) confirmed the an infection with the New World screwworm (Cochliomyia hominivorax) by way of photos of the larvae on Aug. 4, in line with Axios.
“That is the primary human case of travel-associated New World screwworm myiasis (parasitic infestation of fly larvae) from an outbreak-affected nation recognized in america,” Nixon mentioned in an emailed assertion to Axios. Nevertheless, “the chance to public well being in america from this introduction may be very low,” he added.
C. hominivorax is a species of parasitic fly that lays eggs contained in the open wounds, eyes, noses or mouths of warm-blooded animals. Feminine screwworm flies can lay as much as 300 eggs at a time. When the eggs hatch, screwworm larvae use their sharp mouths to burrow into the host’s flesh, which causes a painful infestation referred to as myiasis.
New World screwworms primarily have an effect on cattle and different livestock, however they will additionally trigger infestations in people. An infestation will be deadly if left untreated, however a health care provider can normally deal with myiasis by eradicating the larvae. Individuals who work with livestock, have weakened immune programs, open wounds, or who sleep outside are most in danger for creating an an infection, in line with the CDC. However as a result of screwworm is an insect and never a virus, it’s not contagious, Max Scott, a professor of entomology and plant pathology at North Carolina State College, advised NPR.
The New World screwworm is endemic to South America and the Caribbean, and it is not sometimes discovered within the U.S., in line with the CDC. No circumstances of screwworm infestation have been present in U.S. animals to this point. Within the Sixties, the U.S. eradicated New World screwworms inside the nation by releasing male sterile screwworm flies into infested areas. The sterile flies mated with wild feminine flies, however the eggs did not hatch, which brought on screwworm populations to say no.
Since 2023, screwworm populations have been growing in Central America and slowly spreading northward. In November 2024, a screwworm infestation in Mexico prompted the U.S. to quickly pause livestock imports on the southern border. Imports resumed in January, solely to halt once more in Could. Ports at the moment are reopening in phases, in line with the U.S. Division of Agriculture, and a brand new sterile fly dispersal facility is being constructed in southern Texas.
