Don’t freak out

The chances are low, but not zero.

The tip of a screwworm fly larvae.

Ravenous, flesh-eating flies have busted through containment barriers and have now reemerged in the US. On Monday and Tuesday, the US Department of Agriculture reported three new cases, bringing the tally to five.

One of the cases is in a dog, though it’s unclear where it became infected; the dog lives in New Mexico, had its infection reported in Texas, and may have recently traveled to Mexico, where the flies are also spreading. But the other four US cases were all in Texas—and all in calves—two in Zavala County and two in La Salle County.