US confirms nation’s first travel-associated human screwworm case connected to Central American outbreak

https://nypost.com/ ^ | Aug. 25, 2025 | Reuters

[bitt]

The US Department of Health and Human Services on Sunday reported the first human case in the United States of travel-associated New World screwworm, a flesh-eating parasite, from an outbreak-affected country.

The case, investigated by the Maryland Department of Health and the US Centers for Disease Control and Prevention, was confirmed by the CDC as New World screwworm on August 4, and involved a patient who returned from travel to El Salvador, HHS spokesman Andrew G. Nixon said in an email to Reuters.

Earlier, Reuters reported that beef industry sources said last week that the CDC had confirmed a case of New World screwworm in a person in Maryland who had traveled to the United States from Guatemala.

Nixon did not address the discrepancy on the source of the human case.

“The risk to public health in the United States from this introduction is very low,” he said.

The US government has not confirmed any cases in animals this year.

The differing accounts from the US government and industry sources on the human case are likely to further rattle an industry of cattle ranchers, beef producers and livestock traders already on high alert for potential US infestations as screwworm has moved northward from Central America and southern Mexico.

The government’s confirmation of a screwworm case comes just over a week after US Department of Agriculture Secretary Brooke Rollins traveled to Texas to announce plans to build a sterile fly facility there as part of efforts to combat the pest.

The USDA has estimated a screwworm outbreak could cost the economy in Texas, the biggest US cattle-producing state, about $1.8 billion in livestock deaths, labor costs and medication expenses.

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TOPICS:
KEYWORDS: flesheatingparasite; screwworm

[Openurmind]

True...

[iontheball]

As it is today with the ‘news’, this story is sorely lacking in detail. There is no reporting on how the Maryland resident was infected. We know the vector is a fly. It is attracted to open wounds or mucus membranes and lays a large number of eggs near the wound. The larva hatch in a very short time, crawl to the open wound, and burrow into fresh flesh. It is a worm that feeds on healthy flesh, not like ordinary worms that consume dead flesh, and the wound will grow rapidly larger with time if not quickly and properly treated. Apparently, if the worm is not irradiated from the wound, secondary infections may occur in the body and in some cases even death of the animal. While the resident was in a screwworm infested region, it still would be nice to know how this rare human case of infection occrred.

[Wally_Kalbacken]

Call me a traditionalist, I prefer the Old World Screwworm.

[blackdog]

Skunks, mosquitoes, leaches, ticks, bot-flies, liver flukes (all the parasitic worms you listed), lice, hornets, wasps, and river eels. When I do see God, I want to know just how bad a day can be, that he would make those “things”?.

[Bayard]

maybe, it seems like a bit more on the macro infestation scale though, the larva drill or burrow deep into living tissue such as open wounds or soft flesh to escape and are actively eating the host alive.

[deport]

The New World screwworm fly was the first species upon which the sterile insect technique was tested and then applied in a natural environment, resulting in the control and systematic eradication of this species from the United States, Central America, and parts of the Caribbean beginning in the 1950s.[2] By the early 2000s, it was considered eradicated from North America. However, in 2024 and 2025, the New World screwworm was once again detected in Mexico,[3] leading to renewed efforts to prevent its re-emergence as a threat to agriculture.[4] Meanwhile, the fly is still widespread in tropical and subtropical parts of the Caribbean and South America, so that animals imported from these areas to non-endemic regions must be inspected or treated to prevent the pest’s reintroduction.[5]

https://en.wikipedia.org/wiki/Cochliomyia_hominivorax