U.S. reports first human case of flesh-eating screwworm in traveler from El Salvador.

The U.S. has reported its first human case of the New World screwworm, a flesh-eating parasite, in a Maryland resident who recently traveled to El Salvador. Though rare in humans, the parasite primarily affects livestock. The patient has recovered, and the risk to public health is considered low. The U.S. had previously eradicated the parasite in the 1960s, but it has been spreading northward from South America. Preventative measures include building a sterile fly production facility in Texas.