In early October, New World screwworms were detected in Key Deer in South Florida. The screwworm is a scourge that plagued cattlemen in Florida into the 1950s, and the detected pest has thrown the ag industry into serious action. Commissioner of Agriculture Adam H. Putnam has declared an agricultural emergency. Find out what’s going on, and what you need to know, about the New World screwworm.

Screwworm Information

The New World screwworm is a parasite that has two main life stages: the destructive maggot that gives the pest its name and the adult fly that spreads the insect by laying eggs. The adult fly, a member of the blow fly family, lays eggs in open wounds on cows and horses and other livestock, warm-blooded animals and pets, and even humans. The hatched maggots feed on the wound, which makes the wound bigger and attracts more screwworm flies to lay more eggs.

The resulting wound is a source of infection and blood loss. A screwworm infestation can easily kill the host animal. Many of the Key deer infected died from the infestation. The screwworm was once a major pest in Florida, but it was eradicated from this country—but not the world—by massive efforts. The current detection of the pest in Florida is a huge concern.

There is currently an ongoing quarantine of the Keys, and all animals coming out of the Keys must be inspected for infestation. Additionally, USDA Incidence Response Teams are surveying the infestation and releasing sterile male flies, the successful method used to eradicate the screwworm from Florida in the 1950s.

The FL Dept. of Agriculture and Consumer Services urges everyone in Florida with warm-blooded pets and livestock to check their animals thoroughly and often for signs of infestation.  Potential cases can be reported to 1-800-HELP-FLA or referred by your veterinarian. If the infestation is found soon enough, the larvae can be removed and the animal will recover. Wounds that won’t heal or that are draining excessively should be looked at by a veterinarian. Only trained entomologists can determine if the larvae or maggot is in fact that of the New World screwworm fly.

With vigilance and the cooperation of all involved, the screwworm can once again be a pest eradicated from Florida.

Griffin Fertilizer is committed to helping both growers and ranchers make sound agronomic and economic decisions in order to maximize the health of their grove and pasture. As a full-service custom dry & liquid fertilizer blender and crop protection product distributor, we will continue our mission to further advance Florida agriculture. For questions or concerns about your farm or pasture, contact us and one of our team will be in touch.