A culprit moving our way from the south could devastate livestock and cost the U.S. economy billions of dollars.

The New World screwworm — or NWS — fly produces maggots that cause severe soft tissue injuries. Unlike those of other flies that eat dead tissue only, NWS maggots burrow into live tissue. Untreated animals often develop secondary infections and can die in a week or two.

The U.S. government is taking this threat seriously. The Food and Drug Administration has been granted emergency use authorization for certain animal drugs to treat or prevent NWS infestations. In addition, a planned $750 million dollar facility in Texas is expected to produce millions of sterile flies to reduce the NWS population.

Livestock producers and veterinarians on the front lines are also key players in the fight.