36 million dead birds later, the world begins to end the bird flu outbreak
The toll from the H5N1 avian flu has exceeded 36 million dead birds this year in the United States alone, and the same order of magnitude has been reached in France. Spain has concluded the epidemic after having registered in recent months a total of 31 outbreaks on farms in Andalusia and Castilla y León (with more than one million birds affected) and 37 outbreaks detected in wild birds.
Although this flu has a high mortality rate in birds, most of the birds considered affected are slaughtered before contracting it. The virus also does not currently present a considerable risk to people.
Little danger to human health.
Despite the high number of infected birds, last week only the second case of transmission to people was detected, an American inmate who worked on a large farm. Infections in humans are extremely rare and occur only in cases of close contact between people and infected birds. The first case detected corresponded to a worker in the British poultry sector who did not develop symptoms due to the infection.
According to the US Centers for Disease Control and Prevention (CDC), just over 880 people have contracted the disease since 2003. Current strains of H5N1 are not as dangerous to humans as those seen in previous outbreaks. The main danger of these outbreaks is that the virus mutates to more easily infect humans and other mammals.
Economic losses not only for farmers.
The effects of these outbreaks also have an economic dimension. One of them is its possible impact on inflation, since the US was already warning about the increase in egg prices caused by these outbreaks. That in addition to the economic losses that they suppose for ranchers and insurers.
Controlling the virus is therefore necessary, not only to avoid possible damage (health and economic) to humans, but also due to the damage that the virus causes in birds. Not only is its mortality rate high, but it also causes respiratory problems, diarrhea and sometimes inflammation.
Controversy over the sacrifices.
In the United States, the tools to control this infection have generated some controversy, as farms often resort to a technique called vent closure (ventilation shutdown), a method that involves raising the temperature of the enclosure in which the birds are kept until they die from the heat or excess CO2.
It is a process that was approved by US authorities during the bird flu epidemic that devastated the country’s farms in 2014-15 and left 50 million birds dead. The level of industrialization of the breeding process in the American country generates a perfect breeding ground for the spread of the virus: On the one hand, due to the size of livestock farms, which can reach a million birds; and on the other because the low genetic diversity of birds makes them more vulnerable.
How does bird flu get on farms?
Once a case is detected on a farm, the infection can spread very easily through the farm, but how the first cases reach the farms does not seem so obvious. Those responsible are usually wild birds. Direct contact between farm birds and wild birds is not necessary for these infections to occur. It is enough for the birds to fly over the environment so that the virus enters the livestock farms through their depositions.
