The strain of influenza or avian flu called H5N8 is not new, but on February 20 it was detected among employees of a farm in the Russian Federation, and this confirms that it is a variant with, like others of this pathogen, zoonotic capacity; it can be acquired by humans if they have direct contact with infected birds or contaminated surfaces. Despite this, the transmission of this flu from one person to another is still not ruled out.
That is why, considering that this subtype of the virus, which is very contagious among poultry, and has never been detected in people, an official pronouncement from the World Health Organization (WHO) is expected, and to be treated certainly from an animal-to-human contagion, it would be an unprecedented novelty that occurs in the midst of the covid-19 pandemic derived from Sars-Cov-2 that has left at least 2 fatalities on a global scale.
The organization is still collecting all the relevant information on the case, but the WHO's criteria on avian influenza is that the transmission of this flu occurs very rarely in people, precisely because it requires close contact. However, he warned that this virus must continue to be monitored, since it has great "mutation potential", that is, another variant may emerge and have a greater impact on humans.
"The circulation of certain variants of avian influenza in poultry around the world is of public health concern, because they can cause serious diseases in humans, who have little or no immunity to the virus," indicates the international body.
In the same vein, Anna Popova, head of the Federal Surveillance Service for the Protection of Consumer Rights and Human Welfare of Russia, emphasized that, despite the fact that the microorganism has already overcome the barrier between species, with the H5N8 variant "It is not transmitted from person to person today." But he agreed with the WHO, said that the rapidity of mutations can allow it to evolve and it is possible that it "learns" to be transmitted between humans.
The flu is classified into three types: A, B and C. The first type occur in people and animals with different manifestations, while the type B circulate only among people causing seasonal epidemics. On the other hand, type C viruses are those that slightly affect people and pigs.
In this sense, the WHO has clarified that humans can contract the avian influenza virus and other zoonotic viruses of subtypes A, specifically, the strains: H5N1, H7N9 and H9N2, in addition to the variants of the swine flu AH1N1 and AH3N2.
But what is the zoonotic capacity of a virus?
It derives from zoonosis, which refers to those diseases that can be transmitted from animals to humans, and there are two forms of infection: direct and indirect. The first corresponds to those that are spread between animals and humans through saliva, bites or air, while the second, are transmitted by a species that is a carrier of the pathogen.
They are classified into four types: viral, among the best known are yellow fever, rabies, Ebola or Zika, and avian flu itself; fungal infections such as ringworm and cryptococcosis; bacterial ones, such as salmonellosis, tuberculosis or bubonic plague; and parasitic ones associated with fleas, leishmaniasis, scabies or toxocariasis.
From the point of view of public health, the doctor Juan José Celis, from the J Soteldo Group, explains that what was released by the Russian authorities is not a new flu, it is a common cold among birds, but not yet the consequences that this strain can cause in humans are known.
"What is known is that there are similar strains that have generated epidemics and endemics, so the scientific value is important to help us understand the virus, the damage they cause to human beings and produce a possible vaccine", express.
In conclusion, avian influenza is a viral disease that is constituted by a virus composed of two proteins that have hemagglutinin and neuraminidase on their surface, they refer to H and N, respectively. It is a rapidly spreading pathogenic influenza, causing high mortality in most species of poultry.
There are 18 hemagglutinin subtypes and 11 neuraminidase subtypes, specifically, from H1 to H18 and from N1 to N11, with multiple combinations such as H5N8. Before this, only two strains had infected humans: AH5N1 and AH7N.
We are not facing another pandemic
Until now, the virus is not a cause for alarm for health authorities, because it is known that it is not transmitted from person to person, a carte blanche to prepare an adequate and timely response to future scenarios, taking into account the circumstances in those that the global society is still with the covid-19.
This discovery paves the way "to develop test systems and organize vaccine platforms before this virus becomes more pathogenic, dangerous for humans and acquires the ability to transmit from person to person," explained Anna Popova of the Russian center.
Although there is no indication of a crisis with this variant, it is important to know that influenza pandemics are unpredictable and have high consequences on health and economic systems, as well as social ones.
There are several factors that come together in an influenza epidemic: the appearance of an influenza virus of zoonotic origin capable of mutating from person to person, and the lack of immunity of the population against it, considering the social interconnectivity that cancels a effective response to the crisis.
Juan José Celis added that, generally speaking, in epidemiological terms, we speak of four segments: endemics, outbreaks, epidemics and pandemics. "Actually, we are not facing an endemic or epidemic, much less a pandemic, it was simply announced of an outbreak that was generated and affected a group of workers," he says.
In fact, in 2015, the US Centers for Disease Control and Prevention (CDC) noted that the risk of a pandemic that “has a significant impact on public health if - H5N8 - achieve a sustained transmission from person to person, it is low-moderate ”.
Since 2019, several nations in Europe have detected avian influenza viruses of the H5N8 subtype, such as Poland, the Czech Republic, Hungary, Germany, Romania. Hungary and Slovakia, forcing governments to slaughter thousands of birds as a preventive measure.
Only between December 30, 2019 and January 18, 2020, European countries reported more than 20 outbreaks of the H5 flu virus. In the spring of 2017, an outbreak of the AH5N8 subtype was also recorded in poultry and wild birds, affecting the same territories. Millions of birds were slaughtered.
The World Organization for Animal Health (OIE) reports that H5N8 from avian influenza was known in the 80s, while since 2014, cases have been reported in birds in the northern hemisphere. Russia also had wild-type outbreaks in 2020, as did China, Iran, Japan, and South Korea, and more recently in nations in Africa.
Recommendations for prevention
The OIE also ensures that there is no relationship between influenza strains and the current pandemic of the covid-19 disease, according to the characterization of influenza made by the WHO. Although the existence of this variant is a situation that has occurred mainly in Europe, it is important to put into practice basic preventive methods, which have become very common in the current health situation.
- It is recommended that agricultural workers, veterinarians and others, use means of sanitary protection and maintain good hand hygiene.
- It is important to avoid having direct contact with sick or dead birds; It is also essential to expose yourself without the proper means of protection to contaminated spaces.
- Individual responsibility has an impact on the collective conscience: if you know of a case of suddenly dead birds, inform the health authorities as soon as possible.
- Use gloves or plastic bags if it is essential to collect a dead bird; quickly wash your hands with soap and water.
- It is also essential to make a safe use of food, such as cooking enough poultry and wild birds that you destine or acquire for consumption.