The invading parasitic New World screwworm (Cochliomyia hominivorax) is digging its sharp mouth hooks deeper into the United States.

This week, federal and local officials in Texas confirmed the first known infestation of screwworm in wildlife since the parasite reemerged in the country this year—a female elk killed by hunters. Though total cases of screwworm are still low, this month has seen an increase.

“We encourage all hunters and landowners to be vigilant for signs of New World screwworm while they are out in the field this season,” said Alan Cain, Wildlife Division Director in the Texas Parks and Wildlife Department, in a statement released Wednesday.

The screwworm is actually a species of fly, though its larval form is the real cause of concern. Unlike many species, screwworm maggots love feeding on the living flesh of warm-blooded animals. The flies lay eggs on a host via open wounds or mucous membranes, and then the maggots use their screw-like bodies and sharp mouth hooks to burrow themselves deeper into the animal. This can cause extensive, even life-threatening tissue damage to the host, as well as raise the risk of serious secondary infections.

S. and other countries in the Americas had pushed back the screwworm for decades, creating a barrier as far down as Panama. Recently, however, this barrier has fallen, and the parasite has steadily reestablished itself northward. S.

Source link