The first infestation of screwworms found in Effingham County was on July 18, 1934. By 1959, the entire southeastern U.S. became free of screwworms due to eradication.
It was believed that it came to the South in cattle shipped into this area.
The screwworm is a parasitic fly known for its ivory colored screw shaped larvae that infest open wounds. It became a serious threat of livestock, domestic and wild animals in the southeast in the 1930s. Incidence peaked in warm weather.
The larvae are about seven-tenths of an inch long. The fly is a species of blowfly that is bluish green with a reddish yellow face and three black stripes on the upper thorax between the wings.
Flies lay eggs on the skin of the animal host near open wounds in a shingle like manner that resembles fish scales. The larvae hatch into maggots within a day and use their hook like mouth to tear into wounded flesh and then to invade healthy tissue. Wounds that attract screwworms are: barbed wire cuts, ear marks, branding, bruising or scratches from thorns or fights, castration, dehorning, tick bites, shearing, sore mouths in sheep and shedding of velvet in deer. Navels of newborn animals are a common site and the occasional human was infested.
Wounds often looked swollen and movement could be seen under the skin.
Quickly the larvae fed and the wound became bigger usually killing the animal within a few days to two weeks unless treatment was begun. The wild animal population, including deer, was also much depleted by the screwworm.
This was very costly to the farmers and ranchers in the nation. An estimate of loss in the years of infestation was at $400 million annually in the U.S. The USDA set up guidelines for treatment.
The Springfield Herald reported in August 1934 that County Agent L. V. Cawley gave a demonstration at Egypt on proper methods of treatment where forty interested farmers attended.
Supplies for treatment were distributed at cost with the farmers providing their own containers for storage.
The wounds were cleaned with benzol by irrigation without enlarging the wound, removing the maggots and then Pine Tar Oil was applied. The supplies were available at: the Union Store in Springfield, Sweats Pharmacy in Guyton, Powers Pharmacy in Guyton, Rountree’s Store in Egypt, Z. J. Dasher’s Commissary on Louisville Road, Mallory’s Store in Clyo and Fischer’s Garage in Rincon.
Later on, according to Bill Rahn, the remedy was a product called Formula MS62, also known as Smear 62. You would remove as many worms as possible while cleaning the wound without cutting or further opening the wound and then apply the salve.
Much of the early treatment was aimed at prevention. Animals had to be inspected daily for any broken skin, bruises, wounds or drainage, including the ears.
In the days of no fence laws with roaming livestock foraging for food, this proved especially difficult and time consuming. Many livestock losses occurred. It was recommended that animals infested and being treated be kept shut up in a pen for regular treatment and close observation.
Some animals needed the services of a veterinarian but often the cost versus value of the animal negated what was probably necessary because the nation was also in a depression and later on during the infestation we were at war. It was recommended to avoid ear marking, dehorning, castration and branding during warm weather. Recommendations were that animals be bred to give birth in cooler months.
When infested animals died, proper disposal was recommended. Dig a trench near the carcass, make a good fire of wood in the trench and turn the animal into the pile of burning wood and burn. Deep burial was the less desired alternative. Early preventive treatment of any minor scratch or wound was necessary to prevent animal loss.
Some men in the Springfield Methodist Church tell of the late Harris Rahn apologizing for being late coming into Sunday school one Sunday morning stating that he had been busy treating just about every animal on his place for screwworms. He said that he had not looked at his wife Mary, but if he had she might have had them, too. See the photo.
The first research done in Georgia was in Valdosta at a research lab. Since the flies lay as many as 2,800 eggs through a 31-day life cycle, the wounds could be infested over and over with new larvae hatching at intervals in as little as every 12 hours.
It was determined that biological control was necessary. By developing sterile male flies with releases of new male sterile flies in each location of the country targeted for eradication on a careful schedule that the flies eventually would result in only sterile offspring.
This plan was tried on the island of Curacao with good results. A lab to grow the flies was built in Florida and the sterile fly releases proved effective, there, too, and then other areas of sterile fly releases followed including Georgia.
The South was free of the screwworm by 1959, although it was later in Texas and the Southwest before eradication was accomplished. Mexico played a role in this due to its proximity. International collaboration brought good results.
A plant was built to breed the flies in Texas and later timed sterile fly releases and a plant in Mexico brought eradication. Gradually the control has spread into Panama and other countries south of Mexico.
In 1966, the U. S. was free of the screwworm.
Even now animals imported into the U.S. are carefully inspected and elaborate treatment of infested horses or dogs is done to prevent reoccurrence of the terrible pest that drained our economy. Huge financial losses certainly were eliminated with the vital research and solution of the sterile flies that eradicated this problem.
Many months ago I received a call from Mr. Alvin “Doc” Rahn asking me to do a story on screwworms. With help from former County Agent Wingard W. “Bill” Rahn, and the U.S. Department of Agriculture bulletins along with old issues of the Springfield Herald the story finally came to fruition.
This article was written by Susan Exley of Historic Effingham Society. If you have comments, photos or information to share contact her at 754-6681 or e-mail: susanexley@historiceffinghamsociety.org
