The US has drawn up plans to breed billions of flies to attempt to eradicate a flesh-eating maggot.

The maggot, the larvae of the New World Screwworm fly, is threatening to wreak havoc on the US beef industry, as well as endangering wildlife, household pets and in rare cases, people.

American scientists will breed, and then sterilise hundreds of adult male screwworms, before dumping them from aircraft over Mexico and southern Texas.

The plan is for the female screwworms to have no other choice but to breed with the sterilised males, eradicating the chance of any flesh-eating young being produced.

The larvae hatch shortly after the fly lays its eggs and start devouring anything nearby, before developing into adult flies.

The maggots are endemic in an array of countries in south and Central America as well as Cuba, Haiti and the Dominican Republic.

‘Exceptionally good technology’

The US believed it had eradicated the screwworm from its own territory as far back as 1966, but there are fears that it is spreading north again.

This led to the US banning the import of live cattle, horses and bison across its southern border in September.

Slightly larger than a housefly, they are known as screwworms because of their ability to burrow into flesh.

The US Department of Agriculture is breeding male flies, which are then sterilised with radiation before being released.

They then mate with females, but because the males are sterile, the eggs do not hatch, and it is hoped, the population dies out.

“It’s an exceptionally good technology,” said Edwin Burgess, an assistant professor at the University of Florida who studies parasites in animals, particularly livestock.

“It’s an all-time great in terms of translating science to solve some kind of large problem.”

The screwworm fly factory in Mexico is due to be operational in a year, with the distribution centre planned for Texas.

There is already a fly factory in Panama, capable of breeding up to 117 million flies a week. But that is now considered inadequate by the US, which wants to quadruple production and has earmarked nearly $30 million for the project.

The maggots’ flesh-eating capabilities can also be useful.

In 2019, the UK government funded a programme which would send medicinal maggots to war zones, where they would be used to clean wounds, adopting a technique once used by Australian Aborigines.

They are also being used in the NHS, resurrecting a practice which died out with the advent of antibiotics in the 1940s.