H5N1 outbreak warned

H5N1, better known as avian flu, is part of the influenza A class. The strains of this virus mainly attack birds, both wild and farmed, but can also infect mammals such as weasels, foxes, sea lions, among others.

In January, the Pan American Health Organization (PAHO) issued an alert on outbreaks of avian influenza in birds in countries on almost every continent; the World Health Organization says the situation is “worrying”. The news of several outbreaks of this virus spreading in several countries may characterize one of the worst outbreaks of avian flu ever seen in animals. But, before understanding whether another pandemic could be close at hand, what is the H5N1 virus and what is its mode of transmission?

H5N1
“The name bird flu is the popular name. But for the H5N1 virus, the correct name is influenza A virus. It is called by that name because it has two proteins in its composition: one called hemagglutinin and the other called neuraminidase. These two proteins are what give the names to these viruses, so when I have, for example, the H1N1 virus, I have the glycoprotein hemagglutinin type 1 and the neuraminidase type 1”, explains professor Jansen de Araújo, from the Laboratory for Research on Emerging Viruses at the Institute of Biomedical Sciences at USP, and also a participant in the PREVIR Network (Virus Surveillance Network Project) of the Ministry of Science, Technology and Innovation

There are several combinations that can be made with the rearrangement of these and, in the case of avian flu, it is seen that some subtypes of type 5 hemagglutinin are highly pathogenic and cause diseases, as Araújo puts it. The popular name of this disease comes from its great ability to spread among birds and also from its high mortality rate in these species.

On the transmission of the virus, the professor points out: “It is transmitted through the air, much like the coronavirus, by aerosol. The animals that become infected are common birds or, in this case, we are seeing a lot of cases in wild wild birds. And who gets contaminated? Anyone who comes into close contact with these animals, whether in the backyard, the handler, the owner of the animal, or on large farms, those people who work, who are in direct contact, can end up becoming infected”. However, the similarity with the coronavirus is not only in the mode of transmission, the concern of a pandemic in humans is also a relationship between the two viruses.

Pandemic
“In this epidemic, a pandemic is almost being declared in relation to animal cases, it is already spreading in almost all continents. We have outbreaks, outbreaks, already confirmed”, says Araújo about the situation of the animals. The professor believes that a pandemic in humans is more difficult to occur, since a mutation in the virus is necessary to increase dissemination in humans: “This virus of the H5N1 subtype does not have such great ease of transmission from human to human, so much is it that several cases are occurring in aviaries, in migratory birds, in wild birds, with high mortality and few cases, until now, registered with infection in humans . For now, our concern is that, if such a virus manages to adapt to the human population, then yes, we could think of a next pandemic ”.

In addition to the sanitary part, which is extremely important, Araújo highlights the impact that the transmission of the virus can have on the Brazilian economy: “I think it is fundamental for us to pay attention, here in Brazil, to the economic part. This virus causes great damage to large productions of chicken, poultry and eggs in general. We have never followed a scenario so fast and getting so close to our country. We have a strong economy, Brazil is considered the largest exporter of chicken meat on the planet. Other powers such as the United States and China lost market share when cases of avian influenza were identified in the country and Brazil today is one of the only major producers of chicken meat that is still free of this virus in poultry“. Brazil is currently the largest chicken exporter in the world.and the presence of the H5N1 virus in its territory can immensely harm this position and, consequently, the entire production and consumption chain of poultry and its derivatives.

care
So far, Brazil has not registered any cases of H5N1 contamination. However, this is only possible thanks to constant monitoring and study by laboratories and institutions, such as the Laboratory for Research on Emerging Viruses at USP.

Professor Araújo explains the importance of these observations: “I would like to point out that we are working, in fact, we have never stopped doing this work of monitoring and surveillance of wild birds in different biomes of Brazil, from North to South, on migratory routes, in breeding sites, places where the birds stop here in Brazil before returning to the Northern Hemisphere, or when they come here on their migration. So, we have been doing this work for a long time, we have a lot of experience with it and we continue to do this surveillance and any information, any detection or any new virus that we find, this will be notified to the responsible bodies, such as the Ministry of Agriculture, the Ministry of Health, so that measures are taken as soon as possible“.