What is screwworm and
what causes it?
Screwworms are the larvae (maggots)of a certain fly species that feed on living tissue of animals.
Although these flies have been eradicated from the United States, Mexico and Central America, they can still be found in some countries of South America,the Caribbean, Southeast Asia, India and Africa.
One of the concerns with this parasite is that it will be reintroduced into the United States from an infested animal.
The larvae cause great damage to the hides of animals as well as have the potential to cause death in affected animals.
Screwworms can infest all warm blooded animals, including birds.
Most cases occur in cattle, goats and sheep.
Screwworms (vector) are transmitted when a female fly lays her eggs on a superficial wound of an animal.
Screwworms can infest a wide variety of wounds (e.g. tick bites, dehorning or branding wounds, wire cuts,and other injuries). Navels of newborn mammals are a common site for screwworm infestation.
Wounds infested by screwworms often attract other female screwworms and multiple infestations are common. Screwworm flies can travel from over 12 miles.