First human case of a deadly flesh-eating parasite detected in US. Here's what to know about new world screwworm, what it looks like and symptoms.

W aking up this morning, you may have seen the news that the US has reported its first human case of travel-associated New World screwworm – and most likely, along with the words “flesh eating parasite”. Those are some scary sounding words, but what exactly is New World screwworm, and how concerned do we really need to be?

A Maryland resident who traveled to El Salvador has been diagnosed with New World screwworm — the first reported U.S. case tied to travel to a country with a current outbreak. The Centers for Disease Control and Prevention confirmed the diagnosis on Aug.

Understanding the New World screwworm blowfly and its behavior underscores why it is so dangerous to the livestock industry.