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  • Writer's pictureThe San Juan Daily Star

Cats with bird flu? The threat grows.

By Zeynep Tufekci

The global H5N1 bird flu outbreak, already devastating wild birds and poultry, keeps spreading to mammals, bringing it one step closer to a potential human outbreak.

Of course, since the coronavirus pandemic taught us the importance of responding early and aggressively to outbreaks …

Sorry, I’m joking, we don’t seem to have learned much from the COVID outbreak, and it’s not funny.

Not enough has been done about an out-of-control H5N1 outbreak at fur farms in Finland, or a mystery outbreak among domestic cats in Poland.

Finland, one of Europe’s biggest fur producers, is battling outbreaks among its captive minks, foxes and raccoon dogs — species that scientists warn have been identified as more likely to evolve a variant that can infect people, leading to a human outbreak.

Even the Finnish Food Authority, in its announcement of animals being culled, noted that minks are susceptible to both human and bird flu. If one animal is infected by both, the viruses can mix genes and give rise to an avian flu that can infect humans. Fur farms in Finland, however, aren’t being closed. Instead, the Finnish Wildlife Agency allowed fur breeders to kill wild birds near their farms in large numbers. The agency told me the killings were authorized “to prevent contacts between infected birds and animals at fur farms,” but scientists point out this is the wrong approach and likely futile — and more fur farms in Finland have since announced further outbreaks.

Meanwhile, officials said a sizable outbreak of H5N1 among pet cats in Poland this summer killed at least 29 animals, though cat owners have compiled lists with as many as 89 sick animals. The outbreak has many unusual features that makes it especially concerning, and yet there still hasn’t been an explanation to how exactly it happened, or a vigorous investigation.

The affected cats lived in different areas of Poland, yet their viruses had almost identical genetic sequences. They obviously couldn’t have infected one another. Wild birds are unlikely to be the source, especially since some of the cats never went outside and the outbreak was not detected in Poland’s neighbors. It seems clear that the outbreak originated from a source in Poland.

Scientists and cat owners suspect cat food.

In a further twist, the virus from all the sick cats in Poland had two specific genetic mutations found almost exclusively among mammals, so either all the cats were infected and then their viruses independently developed these mutations, or the two mutations were already in whatever infected them.

Tom Peacock, who studies influenza at Britain’s Imperial College, told me the most likely scenarios were that either the cats were eating mammal meat from sick animals or meat from birds where the virus had somehow developed these mutations that are normally associated with mammalian adaptation.

Either of these options is alarming, and we still lack answers about how all these geographically separated cats got infected with H5N1.

Scientists in Poland were able to test only five samples of food, and a single sample — chicken meat meant for human consumption that was also being fed to the cat — turned out to be positive for H5N1. However, as the scientific report notes, it’s only one sample, which could have been contaminated after the animal got sick in the household.

H5N1 was also detected recently in two cat shelters in Seoul, South Korea. Authorities suspected cat food as the source and recalled two varieties from one brand. While the investigation there may yield some answers, the situation differs from Poland’s since the Korean cats lived in the same place.

There needs to be extensive testing up and down the food chain, to identify the actual source.

If any such investigation is happening in Poland, however, authorities haven’t provided information about it to the public.

Poland is the European Union’s biggest exporter of poultry, so anything implicating the poultry food chain would be economically concerning.

Poland is also the EU’s biggest operator of mink farms. One obvious worry is whether the minks are getting sick with H5N1, and mink meat somehow contaminating the food chain and eventually reaching the cats.

Unfortunately, though, mink farms in Poland have become wrapped up in the country’s culture wars. A previous attempt to ban mink farms in 2020 almost brought down the government, despite widespread support for the ban. The far right especially mobilized against it. One member of the family that controls the vast majority of the mink farms in Poland said the proposed ban was supported by the same people “who promote LGBT, same-sex marriage, abortion, euthanasia and so on.” The conservative government backed off.

Such shortsightedness isn’t the monopoly of the far right. In the United States, a provision banning mink farming made it out of the House last year, only to be killed in the Senate in a bipartisan effort — with many Democratic senators joining Republican Ron Johnson of Wisconsin, where many mink farms still operate, to strip the ban from the legislation.

What’s going on in Poland’s mink farms? Maybe Poland is doing an exceptional job and avoiding mink outbreaks. But maybe it’s not even noticing them, which is possible even simply by not looking hard enough. A mink outbreak in Spain last year showed that H5N1 isn’t as deadly to minks as it is to poultry — where it can kill 80% to 90% of the infected animals — so an outbreak could go under the radar unless there was a proper effort at surveillance. There’s a danger such milder outbreaks could spark a pandemic, since the early stages may be harder to detect.

Fur animals like minks and foxes are carnivorous mammals that ordinarily hunt in solitude. Caging them together in cramped quarters not only facilitates epidemics, it’s especially cruel.

Such fur species are highly susceptible to many human respiratory illnesses, and not just H5N1. In late 2020, Denmark — then the world’s largest mink farmer — was unable to contain COVID outbreaks in its farms despite much effort, and discovered the minks were generating new variants that were infecting humans. Alarmed, Denmark suspended its mink farms, but they’re now allowing them to start operating again.

We should ban fur farms, which are cruel, dangerous and unnecessary, and increase the surveillance and reporting requirements for H5N1 mammal outbreaks.

Paying off fur farmers in Europe and the United States could be cheaper than dealing with a human outbreak, especially since the industry is already naturally shrinking. Challis Hobbs, the executive director of Fur Commission USA, an association representing mink farmers, told Roll Call that about 100 farms are in operation, down from 257, as consumers move away from fur. China also operates fur farms, but an international deal could be pursued for increased surveillance and, hopefully, even a global ban.

In addition, a situation like that of the mystery cat outbreak in Poland shouldn’t be allowed to pass without a thorough and transparent investigation.

As we’ve sadly found out, borders and jurisdictions are niceties that viruses don’t care about, but the lessons remain unheeded globally.



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