US is now scrambling to use aerial bombs of sterilized flies to halt the spread.

We're on the verge of being screwwormed.

The biological barrier was breached, they're slithering toward our border, and the US Department of Agriculture is now carpet-bombing parts of Mexico with weaponized flies to stave off an invasion.

This is not a drill. Screwworms are possibly the most aptly named parasites imaginable, both literally and figuratively. Screwworms—technically, New World Screwworms—are flies that lay eggs on the mucous membranes, orifices, and wounds of warm-blooded animals. Wounds are the most common sites, and even a prick as small as a tick bite can be an invitation for the savage insects.