News: Recently, U.S.A. reported its first human case of New World Screwworm infestation, involving a person who had travelled to El Salvador.
About New World Screwworm
- The New World Screwworm is a type of blue-grey blowfly.
- Scientific name: Cochliomyia hominivorax, which literally means “man-eater.”
- Naming: These flies are called screwworms because their larvae burrow into the tissue in a screw-like way.
- Distribution: They are usually found in South America and the Caribbean.
- Symptoms of infestation: They include wounds or sores that do not heal, bleeding from open sores, movement of larvae under the skin, and a foul odor from the infected site.
- In severe cases, the larvae can invade deeper tissues such as the brain, leading to sepsis and possibly death.
- Life cycle and reproduction
- A single female screwworm can lay up to 300 eggs at a time, and up to 3,000 eggs during her lifespan of 10–30 days.
- The eggs hatch into larvae that feed on tissue, causing infestation.
- After feeding, the larvae fall to the ground, burrow into the soil, and emerge as adult flies.
- Threat: Humans are targeted rarely, but the risk increases when people travel to regions where the parasite is present.
- The parasite poses a serious threat to livestock, especially cattle, because open wounds on animals provide easy entry points for infestation.
- Control and eradication efforts
- The United States eradicated the New World Screwworm in 1966 using the sterile insect technique.
- This method involved rearing billions of sterile male flies and releasing them into the wild.
- When wild females mated with sterile males, they did not produce offspring, which helped reduce the population.
- The United States eradicated the New World Screwworm in 1966 using the sterile insect technique.
