American livestock farmers are facing an old foe, one previously banished for decades — the New World screwworm fly.
This parasitic fly was once a scourge to farmers in the Southern United States for decades until eradication efforts in the 1950s and 60s successfully exterminated the species here. The efforts consisted of breeding sterile male flies, and introducing them into the population, interfering in the breeding cycle of females, as female screw worm flies only breed once in their brief lifespan.
However, reports of screw worm infections spreading north through Mexico were reported in 2024. Now, as of last week, 12 cases of screwworm infection have been reported, 11 in Texas and one in New Mexico.
Despite the new cases being largely relegated to areas near the southern U.S. border, speculation is growing about the possible impact it could have in beef prices. In response to this outbreak, the federal government has begun putting quarantine zones in place, and has been preparing sterile flies since February.
Local cattleman Gordon Cole “GC” Ganas of Cole ANGUSBeef gave his insight on the issue.
“Local farmers at present have no immediate concern if managing a closed herd,” Ganas said. “Those that purchase animals at market should be very diligent in knowing the animal’s history and source. Close physical inspection should be completed to detect any potential signs of any wounds.”
Ganas was reassuring about the risk to local markets, saying “It’s not likely animals purchased in our regional markets will have any animals that originated from Texas or further West.”
He also emphasized the local role in managing the pest.
“Local markets will become involved in managing this to control further expansion. What to do with animals discovered will most likely be elimination in some controlled manner.”
Ganas concluded that, in regard to screwworm, Georgia farmers have “no need to panic at this currently.”
Dr. Hank Wheeler of Satilla Animal Hospital emphasized the importance of cleanliness and good hygiene in pets.
“Livestock owners should have a good fly control program in place in order to prevent the spread of many diseases including the screwworm,” he said.
He also encouraged regular checking for open sores and wounds, and disinfecting any found.
“If maggots are present then I would recommend the animal be examined by a veterinarian,” Dr. Wheeler added.
The threat a new screwworm outbreak poses to the cattle industry has prompted a response not just from the federal government, but from state governments as well, including Georgia.
