Photo: Mads Claus Rasmussen/AP
If you wanted to deny as many people as possible and kill them without prosecution, what would you do? You would do well to start with bird flu. Avian flu is responsible for all known influenza pandemics: the great influenza that began more than a century ago, the “Asian flu,” the “Hong Kong flu,” and the “Russian flu,” which have killed tens of millions of people. They also cause many of the annual outbreaks that kill hundreds of thousands of people.
Once you have found a suitable variant, two more components are required to arm it. The first is an amplifier. The best amplifier is a huge shed or factory that packs thousands of birds. These birds should be genetically homogeneous so your virus strain can move freely between them. Intensive poultry farms would do very well. Under these circumstances, a low pathogenic strain should shortly mutate into a highly pathogenic strain.
To ensure maximum transmission, move some of the birds faster than the flu incubation period. You could wear them across borders. Some would be relocated to free range or hobby farms to increase the chance of infecting wild birds.
But it’s difficult for an influenza virus to get directly from birds to humans, so another component is needed: a mixing vessel. This is a species that can simultaneously harbor the newly pathogenic avian virus and a species of influenza already adapted to humans. Then, conveniently brought together, the viruses can exchange genetic material – a process called “reassortment”.
Pigs are sensible mixing vessels. They may have played that role in some previous outbreaks and pandemics. But there’s a much better candidate: mink. Mink easily harbor human and avian influenza viruses. As predators, they can easily contract bird flu through the meat they eat. The distribution of sialic acid receptors – a key factor in infection – in their airways is similar to that in humans. Human flu strains can be transmitted between them by aerosol transmission.
Mink also possess what scientists call “zoonotic potential” to a remarkable degree: in other words, they can be and infect from many different species. In the early stages of Covid-19, they proved to be highly effective mediators, partly because the virus appears to evolve faster in mink than in humans. They seem to have given rise to at least two new variants that have spread to humans, one in Spain and one in Italy. Mink are the only species known to have both received and passed on Covid-19 to humans.
To improve their ability to mix, you would cram together hundreds or thousands of the tiny cages they live in, forcing this normally solitary animal into contact with others. You would reduce genetic diversity by only breeding those with a specific coat type. In other words, you would be doing what mink farms are doing today. Then you would sit back and wait.
The next pandemic might not have been seeded by a murderous psychopath, but if we’re not lucky, the impact could be the same. H5N1 was a relatively harmless bird flu until 1996 when a highly pathogenic variant was hatched in a Chinese goose farm. It’s deadly to humans. In the rare cases in which people have contracted this variant, it has usually ended fatally: 457 of the 868 infected people by October last year died. Fortunately, although it has been devastating to both poultry flocks and wild birds, its transmissibility from birds to most mammals and from human to human is extremely low.
But mink farming provides the mixing vessel it needs. In 2021, an article in the journal Emerging Microbes & Infections reported that about a third of the mink the researchers tested contained antibodies to both avian and human flu. It warned that this common infection could create novel viruses “with high human infectivity”. The public health threat “should not be ignored” as it has “pandemic potential”. Needless to say, it was ignored.
A few days ago, the journal Eurosurveillance revealed the first known case of large-scale mammal-to-mammal transmission of the H5N1 influenza virus. It happened, unsurprisingly, on a mink farm; in Galicia, northern Spain. While the mink were fed poultry products, which scientists have long warned against, the likely cause of the infection seems to be contact with a sick wild bird, which may have fallen against the bars of a cage and was dragged through and eaten. Once in its mixing tank, the virus mutated to become transmissible to the other mink and then quickly spread from cage to cage in this farm of more than 50,000 animals.
This epidemic was contained before it left the farm. All mink were killed and we might have just missed out on a pandemic that might be deadlier than Covid-19. But mink farming for their fur, a cruel and senseless practice, continues in Europe, North America and China. There is a high probability that the next pandemic, whatever it may be, will break out in one of these places. Because of the abhorrent cruelty the animals endure and the serious threat they pose to human life, we need a global treaty banning mink farming.
The H5N1 virus, which acquired its deadly mutations on a poultry farm, is now rampaging through wild bird populations with dire consequences. It kills so many that combined with other threats it could drive some species to extinction. In particular, it destroys colonies of seabirds. Since they reproduce late and slowly, they are particularly threatened with extinction. Wild birds could easily carry the virus to another mink farm.
Related: Bird flu is a huge problem now – but we’re just one mutation away from it getting much worse | Devi Sridhar
Accompanying this menace is grotesque cruelty: the fowl, mink, and pig farms whose horrors we’ve somehow normalized and accepted. If you treated dogs or cats like we treat these animals, you would go to jail. But do this on a large enough scale with farmed species, and you’ll be treated with the special respect accorded a ‘captain of industry’. Governments will wipe the dust off your path. Newspapers will write eulogies such as those once bestowed on emperors.
So who is the murderous maniac in this story? It is a barely studied abstraction that we call “the economy,” a monster to which anything and everything must be sacrificed without question or resistance: farm animals, wild animals, even, if we’re lucky, millions of people. We will only prevent the pandemics of the future if we value life more than money.
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