Many cows in the stables and dozens of birds died from bird flu. Could Galicia be the source of a new pandemic?

Health authorities in California (USA) announced two new cases of avian influenza in humans this week. A total of 17 people have become ill in the United States in recent years, six of whom came into contact with dairy cows, and the rest, except one, became infected with the H5N1 virus after contact with poultry. In one case, there is no evidence of contact with animals, suggesting a possible mutation that allowed the virus to jump from person to person. A nightmare scenario that epidemiologists have been warning about for years: Another Covid-like virus, of animal origin, that becomes infectious between people, is beginning to take shape.

North American authorities have classified the risk to humans as “moderate”. The alarming aspect of this issue is that all types of livestock can become carriers of this virus.

Until now, it has affected populations of other species, in particular the American mink raised on fur farms. In fact, in Galicia, the Carral farm had to sacrifice thousands of animals a few years ago after transmitting a virus from wild birds to caged minks.

Among farmed birds, some vectors are known to originate from wild fauna (eg mallards) and can transmit the virus to poultry populations.

The first human death from bird flu occurred in China in the late 90s. 900 cases worldwide with almost 500 deaths.

Given the large cattle population in Galicia and the constant discovery of dead wild birds with avian influenza, with several dozen cases, is it possible that the infection could have occurred in humans similar to those in the United States?

FOR A MOMENT, CALM

Oscar Pose, member of the Agrarian Unions (UUAA), points to the state of calm in Galicia’s livestock sector. In relation to these cases, it is indicated that “These are specific cases” and that the Galician herd of cattle is now out of danger. Moreover, Pose insists that there are few cases in the United States, although they confirm that transmission of avian influenza viruses between birds and ruminants is possible.

“It is known that the first virulent cases occurred in China, and the problem is the mutation of the virus strain that made it virulent.says Ignacio Munilla, biologist.

Recent cases in America have occurred in livestock kept in stalls, especially livestock destined for milk production, which are kept indoors 24 hours a day, much like poultry. That is, A very closed environment and high population density are risk factors for the transmission of this influenza.

ORIGIN AND RESEARCH

There is no certainty about the exact origin of the avian influenza virus, also called bird flu, although it has been known since the late 19th century through cases identified in Italy. Despite this, The first human cases occurred in Asia several decades ago, and from there they gradually spread to the rest of the world.

Viral mutation may accelerate during colonization of new habitats that function as biological reservoirs for all types of species, including viruses and their natural antidotes.

The appearance of humans simplifies the environment and reduces it, which opens up the possibility of the virus strengthening both itself and its carriers (vectors), since there are fewer competitors capable of counteracting them. A reduced ecosystem, such as a stable, is not as reliable as a complete one, and resistance to various diseases is significantly reduced.

Against this background, German and American scientists conducted a series of experiments in high-security laboratories in Kansas. The goal is to find out the cause of the infection in cattle. For this, The virus was experimentally inoculated into calves and cows, as a result of which it concentrated in the udder and milk of cows.According to Jurgen Richt, a scientist at Kansas State University.

European health authorities have not yet reported any possible outbreaks of avian influenza on EU dairy farms. Actually, EFSA (European Food Safety Authority) has not provided any documents or news on this issue to date.

Finally, scientific publications indicate that airborne transmission of H5N1 to humans would mean that the virus would be more virulent. It would be necessary to break down all the barriers of the human immune system, but at the moment it seems that this is not the case.

Regarding milk consumption, EU health authorities note that the pasteurization process eliminates the possibility of human infection through consumption of this product.

At the moment, in Europe and specifically in Galicia there has not yet been any alarm and the authorities are calling for calm.