As Australia lifts its ban on US beef, Mexican cattle ranchers are battling a flesh-eating parasite outbreak

Just as Australia lifts its biosecurity ban on US beef, including cattle raised in Mexico and Canada but slaughtered in the States, ranchers in southern Mexico are fighting against a flesh-eating parasite infecting livestock.

The Albanese government insisted the decision was made purely for scientific reasons after a decade-long review, and not to appease US President Donald Trump, who had complained about Australia's restrictions.

At the same time, Mexican cattle has again been barred from the US over fears of the spread of the New World screwworm fly.

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The flesh-eating parasite burrows into animals and can cause serious to deadly damage, according to the US Department of Agriculture.

It can cause devastating impacts to livestock and is currently rapidly spreading across the southern Mexican state of Chiapas, which borders Guatemala and Central America.

The US Department of Agriculture has issued an alert about the outbreaks.

Mexico is building a plant with US support in Chiapas to produce sterile flies, which have proven effective at stopping the spread, but it won’t be ready until next year.

Meanwhile, the price of medicines used to treat livestock infected with the screwworm has soared.

That has led some to fall back on home remedies like applying gasoline or lime to open wounds to coax out the worms.

In addition to the cost of the medicine, treatment requires careful monitoring and usually involves multiple courses.

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Any open wound, even very small ones, are an invitation to the fly to lay its eggs.

The outbreak comes as Australian farmers have been raising concerns about the risk of importing Mexican beef via the United States following the relaxation of biosecurity controls.

"I wouldn't think that Mexico would have the best biosecurity so why take that risk?" Macka's Angus director Robert Mackenzie said on Thursday.

The Nationals and Cattle Australia have called for an independent scientific review of lifting the biosecurity ban.

"There is simply too much at stake when it comes to Australia's world-leading biosecurity status not to get a second opinion," Cattle Australia chief executive Will Evans said.

"If the department and the government are confident in that decision they've made, they have nothing to fear," Nationals leader David Littleproud said.

US companies wanting to export beef to Australia will need to apply for accreditation from the Department of Agriculture, which will assess whether they meet the nation's tough biosecurity standards.

A blanket ban was placed on beef imports from the US more than 20 years after an outbreak of mad cow disease.

In 2019, that ban was partially lifted for cattle raised and slaughtered in the US, but not for cattle raised in Canada and Mexico but slaughtered in the US – which effectively still barred American beef from Australia.

Yesterday, the Albanese government confirmed it will lift the biosecurity restriction.

Ahead of Australia lifting its ban, the US has put improved cattle tracing protocols in place recently, allowing local authorities to better react to disease outbreaks.

Trump reacted to the news by saying the US is going to "sell so much to Australia", but the Australian beef industry does not expect the foreign exports to have much impact on the domestic market.

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Mexican ranchers fight against outbreak of flesh-eating bacteria

Veterinarian Alfredo Chávez left Chiapas to study in 1989, so he says he missed seeing the effects of that outbreak, but now he has seen cases multiply in his corner of the state over the past month.

He has heard of dozens of cases in the area now and treated about a dozen himself.

It’s not just cows either — sheep, pigs, cats, and dogs are targets as well.

Armed with a pair of blue tweezers and an aerosol spray that helps draw the maggots out, Chávez moves from animal to animal.

He puts maggots in plastic tubes as samples, which he provides to agricultural authorities.

But beyond providing the tubes and encouraging ranchers to report cases, he said that the government hasn't provided much help.

“We’ve faced it alone,” he said on Wednesday.

The US had just gradually started to reopen the border to cattle imports this month after an earlier suspension in May, when the Trump administration said that it would close it again after an infected animal was found in the Gulf coast state of Veracruz.

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While prevalent in Central America, the concern is that the fly is moving north.

US officials worry that if the fly reaches Texas, its maggots could cause large economic losses, something that happened decades ago.

Ranch caretaker Edi Valencia Santos said that Mexican government officials have come to his community to talk to people with livestock, but so far without resources.

He has had five infected animals on the ranch.

Despite cattle in this region going to domestic consumption rather than to the US, the presence of the screwworm in Mexico has frozen cattle exports to the US nationwide.

Valencia said that he remembers the small planes distributing sterile flies during those earlier outbreaks, so is optimistic they will eventually help, but for now the costs are piling up on ranchers.

“It’s a big, big problem in Chiapas,” he said.

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