The seasonal influenza vaccine helps reduce the severity of avian influenza

To prevent transmission, maintain measures implemented against COVID-19, in addition to avoiding contact with secretions from sick poultry and getting immunized every year.

The seasonal influenza vaccine helps reduce the severity of avian influenza
Avoid contact with secretions from sick poultry and getting immunized every year. Photo: UNAM

H5N1 is an Asian strain of influenza or avian influenza that in 2013 became endemic in China and Thailand; however, its spread has now been facilitated mainly by the migration of birds in Europe and the United States, where the virus was detected in humans, although these infections are rare.

This virus still has low pathogenicity in humans, but precautions should be maintained in the handling of infected birds, for which reason it is recommended not to touch live or dead animals detected in wild areas, because they may be infected, to avoid contact with secretions such as saliva and feces of those that are sick, and to maintain the hygienic measures foreseen for handling poultry.

It is suggested to continue with the measures against COVID-19 such as the use of masks, hand washing, and keeping the areas ventilated, among others. This pathogen alerts the community to foresee any type of situation that could generate zoonosis (animal to human transmission) and trigger a new pandemic.

Although there are variants of the microorganism due to mutations from one year to another, the biological vaccine works quite well and helps influenza (seasonal and possibly against avian influenza) not to be so serious. If you have access to it, it is advisable to be immunized annually and to maintain hygiene measures.

The symptoms of this disease in humans vary from person to person but share some of the symptoms of seasonal influenza such as physical exhaustion, watery eyes, occasional high fever, cough, or cold. When it is severe, pneumonia can develop, and even death.

For several years, avian influenza has infected wild birds and poultry in different parts of the world. In other times, some of these viruses infected humans and produced several pandemics throughout history, such as the Spanish flu in 1918; the Hong Kong flu in 1968; and the H1N1 influenza pandemic in the United States-Mexico in 2009. They are different strains, but they are shaped in a very similar way.

These microbes have a segmented genome, and when there are co-infections of two different strains in a cell, viral replication begins, which contributes to the exchange of some genomic segments and the production of different viruses, which are not recognized by the human immune system because they lack previous contacts, so the response against them begins.

Their rapid neutralization by the immune system before they enter the cells and infect them is not always easy, which can lead to respiratory disease. They develop specific mutations that allow them to evade the previous immune response of the host and manage to remain in nature.

All birds, and mammals in general, produce an immune response to stop these infections efficiently and prevent us from getting sick, but it is a process that takes time. The viruses have a natural host; the avian flu viruses are in certain aquatic wild birds, such as diving ducks, without causing them any harm. But when they jump to other species such as migratory birds, they can cause severe damage and even death to some of these animals or others infected by these migratory birds, as happens in chickens, turkeys, pheasants, and other birds.

When wild birds co-inhabit with domestic species, they can cause infections, and poultry is highly susceptible to several of these highly pathogenic influenza viruses.

The economic devastation in poultry animal production, which affects large producers for human consumption, and small producers, who keep chickens and other animals in backyards for domestic or regional consumption, should be underlined. When this disease is detected on farms, practically everything is lost because the animals have to be slaughtered.

Regarding sanitary filters at customs, there are regional alerts in which the presence of infected birds has been detected. There must always be certain sanitary controls, such as strict monitoring carried out in Europe and the United States on migratory birds (when they leave and arrive from other places), detecting whether they have infections, particularly of avian influence, in addition to determining whether they are bacteria of high or low pathogenicity in birds and the subtype to which they correspond. In the case of Mexico, more information is still needed on these migratory movements.