An unpleasant parasite spread by flies was kicked out of the U.S. decades ago — but now it seems to be making its return. As a result, the U.S. Department of Agriculture is changing strategies to confront it.
New World screwworm is a livestock pest that can be a parasite of any warm-blooded animal, laying its eggs in even the tiniest of open wounds or cuts, including the bellybuttons of newborn animals, and in mucous membranes anywhere in the body.
