The person, who received treatment in Maryland, is the first confirmed case in the U.S. of New World screwworm, a parasite that eats cattle and other warm-blooded animals alive, since an outbreak began to escalate and move northward from Central America and southern Mexico late last year.

A Maryland resident has been treated for the New World screwworm, a rare flesh-eating parasite, after returning from Guatemala. This marks the first confirmed human case in the US since the parasite began spreading northward in late 2023.