The first human screwworm case in the U.S. has been traced to a person in Maryland who traveled from Guatemala.

A human case of a flesh-eating parasite known as New World screwworm has been confirmed in a Maryland resident, the first in the United States in years, according to U.S. and state health officials.

The parasite — the larvae of the new world screwworm fly — can devastate cattle herds and is rife in parts of Central America.