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

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

“This is the first human case of travel-associated New World screwworm myiasis (parasitic infestation of fly larvae) from an outbreak-affected country identified in the United States,” HHS spokesperson Emily G. Hilliard told NBC News in a statement.