Why cows are dangerous to start an H5N1 pandemic – 2024-07-16 06:09:50

It is a given that there will be a pandemic from bird flu. The question mark is when, emphasizes the pathologist, with a large research project in infections, doctor of the University of Ioannina Giorgos Pappas, in an interview granted to the Fm Agency.

And another question mark is, of course, how ready we will be for this, underlines Mr. Pappas, pointing out that these enormous evolutionary steps of the virus that are occurring are unexpected and cause experts concern, that the next day may be waiting for us around the corner, the next evolutionary step and for the virus to learn to overcome the human defenses, when it starts infecting him. As Mr. Pappas points out, bird flu has for years remained a prime candidate as a potential cause of some subsequent pandemic. “For at least twenty years there have been preparedness scenarios from the US for such an eventuality.

The problem, however, was that this eventuality required several evolutionary stages on the part of the virus. The bird flu virus does not easily infect humans. It cannot be easily transmitted from person to person. Therefore, it does not have two basic elements to create and start a pandemic. However, it has some other characteristics. That very few people are immune to such a flu, because it is caused by strains that we have not encountered before.”

The evolutionary steps of the virus in the last two years

What has happened, however, in the last two years, according to the well-known pathologist, is that the bird flu in the form of H5N1, began to take huge evolutionary steps. “First it started from Europe to show an extension of its seasonality. It wasn’t just hitting the birds and it wasn’t just causing problems in the winter months, but it started to spread over the course of the year. It then began to infect much more heavily some wild waterfowl and cause mass deaths.

Very characteristic was the example we had in Prespes in 2022, where at least 10% of the total population of silver pelicans died. And although it is described as the biggest ecological disaster that happened in Greece, it did not get the attention it deserved. The virus continued to evolve and passed for the first time through waterfowl in the American continent, not only in the US, but slowly began to descend and reach South America, making some recombinations locally with other strains of low pathogenic avian influenza , which may have circulated there.

The problem is that it started infecting mammals, not only in Europe where we had outbreaks on mink farms in Spain and Finland, not only in foxes, bears and animals that happened to eat a dead bird and become infected, not only in cats in Poland, where last summer we had a lot of outbreaks, because they were fed chicken that was infected. It began mass killing populations such as seals, sea lions, from Latin America, to Antarctica. Fortunately, the penguins seemed a little resilient.”

How close the detection of bird flu in cattle brings humans to a pandemic

But the worst thing, as Mr. Pappas points out, is that since March of this year, cases began to appear in cattle herds in the USA and at the moment there are officially 140 detections of confluence of cases in herds in 12 States of the USA. However, he says, that number is expected to rise. But why are scientists so concerned regarding detection in cattle? “Firstly, cows are an animal that we did not expect to be infected by bird flu. So, the virus has made another big evolutionary leap.

Second and worse, the bird flu virus in cows mainly infects the udders. Scientists have discovered, and there are a number of recent publications, that the udders of cows are a very bad place for a flu virus to go and sit. It is a mixing and recombination vessel and usually, such a mixing vessel in an animal or animal organ is “required” to start a pandemic. That is, humans do not easily catch bird flu, because the receptors they have in the respiratory tract are different from those of birds. In the udders of cows, however, there are both receptors, both human and bird. And this means that the virus has already begun to train and love and stick to both receptors. Therefore, the virus has taken the first step of many that are still required to start systematically infecting humans.” It also infects milk and the virus can be detected in huge quantities, says Mr. Pappas, explaining that if the milk is pasteurized there is no danger.

Greece participates in the pre-order made by the EU for the vaccine

Regarding vaccination starting only in Finland to professionals in contact with fur animals, poultry farmers, breeders, veterinarians and close contacts, due to multiple outbreaks in fur farms (mink, foxes and raccoon dogs) Mr. Pappas is asked why something similar is not happening in Greece, which is the number 2 European country in mink production volume. “We don’t have runoff on our own mink farms as far as we know. Greece has not yet taken decisions on vaccination, but it is participating in the pre-order that the EU made to the company that produces the vaccine, so that some quantities can be reserved for our country.

Fifteen countries of the European Economic Area participate in the order.” But how dangerous can this flu be for humans? “If the virus evolves in such a way that it sufficiently attacks the human respiratory system and adapts to our immune defenses, then it will have the potential to cause a pandemic wave, without us knowing the severity of the symptoms. These will depend on the adaptation of the virus to humans, as well as the fact that no one will be immune to this strain.”