The USA announced yesterday the first case to a man of the “worm of the new world”, a parasite eating the host flesh.

The case was recorded in Maryland and involved a patient who had returned from a trip to El Salvador, according to a statement from the US Department of Health’s spokesman to Reuters.

These are parasitic flies, whose females lay eggs in animal wounds. When the eggs hatch, hundreds of larvae “dig” the animal’s tissue, eventually killing the host if the infection is not treated.

The worm can be catastrophic for cattle and wild fauna. It rarely affects people, though an infection, whether in an animal or human, can be lethal.

The treatment is painful and involves the removal of hundreds of larvae and thorough disinfection of the wounds. However, infections are usually curable if treated in time.

By 2023, this worm has been traveling north via Mexico, coming from Central America. They are endemic parasites in Cuba, Haiti, the Dominican Republic and in South America, according to the US Department of Agriculture.

Mexico reported a new case in July, about 595 kilometers south of the US border in Veracruz. USDA immediately ordered the closure of the entry points for animal trading from the south, having already suspended imports in November and May.

The United States usually imports over a million cattle from Mexico each year for thickening of breeds and processing in beef.

These worms were eliminated in the US during the 1960s, when authorities liberated large numbers of sterile males, blocking the production of new larvae.