Screwworm? What’s the flesh-eating parasite found in a human in the US?

Parasitic flies have been found in the United States, following an outbreak of screwworm in Central America last year.

The United States has reported its first human case of New World screwworm, according to its Department of Health and Human Services (HHS).

The flesh-eating parasite usually eats cattle and other warm-blooded animals, and is fatal if left untreated.

The case, investigated by the US Centers for Disease Control and Prevention (CDC), was confirmed on August 4 and involved a patient who returned from El Salvador to the US state of Maryland, HHS spokesman Andrew Nixon said in an email to the Reuters news agency.

Nixon did not address an earlier report that said a case had been confirmed in Maryland in a person who had travelled from Guatemala. The US government has not confirmed any cases in animals so far this year.