Mexico studies greater than 5,000 instances of screwworm, primarily in cattle and different animals, based on gov’t knowledge.
Revealed On 28 Aug 2025
Mexico has reported a 53 % improve in instances of flesh-eating screwworm in animals over the previous month, because the parasite continues its northward trajectory in direction of america border, based on authorities knowledge.
Mexican authorities knowledge point out that there have been 5,086 instances as of August 17, together with 649 energetic ones, the Reuters information company reported on Thursday, citing up to date knowledge not but made public.
The parasite has been discovered primarily in cattle, in addition to in horses, sheep, and canines, the information outlet mentioned.
There have additionally been dozens of human infections.
Mexico has confirmed 41 human instances over the previous yr, primarily within the state of Chiapas, based on Mexican media. The primary human case was confirmed within the US state of Maryland on August 4 in a affected person who had travelled to El Salvador.
Mexico and the US eradicated screwworm a long time in the past, however the parasite returned round 2023 after transferring northward from Central America.
The infestation has disrupted Mexican cattle exports, with losses valued at $1.3bn over the previous yr, based on the Mexican Nationwide Agricultural Council.
The US Division of Agriculture (USDA) mentioned that left unchecked, screwworm threatens $100bn in financial exercise linked to the cattle and livestock industries.
Screwworm infestations start with parasitic flies that lay their eggs in warm-blooded animals. The eggs hatch into larvae, which burrow into the flesh of their host, killing them if left untreated.
Infections are difficult to deal with, and so is stopping future outbreaks.
The Mexican and US governments are constructing “sterile fly” manufacturing services within the states of Chiapas and Texas to cut back the inhabitants of screw flies.
A sterile fly facility produces a lot of male flies and sterilises them. These are then launched to mate with females within the wild, which reduces the wild inhabitants over time. This technique eradicated screwworm from the US within the Sixties.
The 2 services and one other in Panama might want to produce about 500 million sterile flies every week to push screw flies again to South America, the place the parasite is endemic, based on the USDA.
The US Division of Well being and Human Providers (HHS) has additionally authorised emergency veterinary medication to forestall the parasite from spreading.
They embrace “animal drug merchandise that could be authorised for different functions, or obtainable in different international locations, however not formally authorised” for the screwworm, HHS mentioned.
“The chance to human well being in america stays very low, however the potential future menace to animal populations and the meals provide chain requires proactive motion,” it mentioned.
