Avian flu occasionally resurfaces in a new form. How dangerous is the new H5N8 strain, where is it spread and what does the future hold?
One of the most famous viral strains of avian influenza is H5N1, a virus that in 2003 caused 862 human cases worldwide and 455 deaths, thus with a very high lethality rate (52.8%). Its characteristic, as well as the characteristic of all other strains of avian influenza of which we’re currently aware, is that it’s not transmitted from person-to-person. This accounts for the low number of individuals who’ve been directly infected, solely by birds.
What do we know about the H5N8 avian influenza strain?
Firstly, we must say that it’s not an unknown viral strain. In fact, it’s been circulating on poultry farms throughout Europe for several years. However, it suddenly became famous on February 21, 2021 when Russia announced that it had detected the first case of transmission of the H5N8 avian influenza strain in humans. Russian researchers from the “Vektor” Center, detected the virus in seven employees of a factory where outbreaks had been reported among its poultry in December 2020.
In the past, several cases of avian influenza caused by the H5N8 strain have been recorded. In 2016, H5N8 was present in eight European countries. In 2017, 83 outbreaks were reported in industrial and rural farms mainly in Veneto and Lombardy. In Italy, the last episode of infection was recorded on January 21, 2021, when the H5N8 strain was isolated in two gray crowned cranes in Lugo di Romagna, near Ravenna.
Despite the numerous cases of infection among birds recorded in recent years, the Russian one is the first case of transmission from birds to humans.
However, if we go back further, we must remember that the flu pandemic of 1900, also known as “the old Hong Kong flu”, was caused by an H3N8 strain. Also, the 1968 pandemic, also originating in Hong Kong, was caused by the H3N2 strain that is still circulating. The greatest fear among experts is that there may be recombination between avian influenza strains, leading to increased infectivity of the virus, and that it may generate a strain that is transmitted from person-to-person.
Should we be concerned about a new “Coronavirus”?
Certainly, it’s not an infection that should be underestimated, especially after the lived-through (and still ongoing) experience triggered by the SARS-CoV-2 pandemic. The case of transmission to humans was reported to the World Health Organization (that immediately spread throughout the news), and the WHO made the appropriate recommendations.
From a scientific point of view, we can say that it’s quite unlikely that a strictly avian strain mutates to the point of being able to infect humans, and the very few cases recorded so far testify to this. However, we must remember that precisely because of their potential danger, virus strains of avian origin are being constantly monitored, and even this news that has spread is further proof that the system of control and monitoring is working.
The WHO has issued a recommendation to more closely monitor poultry farms, markets where live animals are sold, and places where people may come into contact with wild birds. It’s to be hoped that measures to prevent and contain any spread of infection to humans will also function properly. The following video is in Italian.
This post is also available in: Italiano