Right now that the cases of Covid are continuously decreasing and all the restrictions have disappeared, there is a new alarm, also confirmed by theWorld Health Organization (WHO): it’s about thebird flu. To worry is the infection, caused by virus responsible for type A influenza among chickens (hence the name ‘avian’), but also among birds and some mammals, such as minks. In fact, experts fear that the disease could also affect themanas the WHO director-general said, Tedros Adhanom Ghebreyesus. To explain a Virgil News what it is, how it is transmitted and what the risks are Massimo Andreoni, scientific director of the Italian Society of Infectious and Tropical Diseases (Smit). What do we know about virus H5N1.
What is avian flu
L’bird flu in itself it is not new, because the H5N1 virus, responsible for the infections, has always circulated between wild and domestic or farmed birds, for 20 years now.
Now, however, what is alarming is the jump of species, with a diffusion also among the mammals such as mink, otters, foxes and sea lions, and especially the possible transmission from man a man.
WHO alarm
L’epidemiologo dell’Oms, Richard Peabody, stated that he feared that the virus H5N1 acquires the ability to spread from person to person, and in a sustained manner, causing a new pandemic.
In this sense, the scientific community is studying the genetic sequence of these viruses in order to monitor them and also develop gods vaccines.
The interview with Massimo Andreoni on flu
Below, the interview granted to Virgilio News from Massimo Andreoni, scientific director of the Italian Society of Infectious and Tropical Diseases
Bird flu has been around for years: is the possible human-to-human transmission of concern?
“Exactly, together with the numbers regarding the mortality of this virus. We bear in mind that there have also been several cases in the past, both in the world and in Italy: the H5N1 virus, which has begun to circulate in the early 2000s, is responsible for over a thousand cases with 500 deathstherefore it has a mortality higher than 50%, to be exact by 53%. It is extremely high: just think that Covid had it below 1%”.
What are the chances that it could become a human-to-human transmissible virus?
“That’s the point. Up to now it hadn’t happened yet, except in one case reported by the England journal of Medicine of 2005, but never confirmed again and therefore in fact remained as an exceptional case of direct human-to-human transmission. The leap of species, the so-called game over, there has already been, but mostly the infections occur between birds. What is worrying is precisely the transition to mammals, because the transition to humans becomes potentially easier and, finally, from man to man. This perspective, which is averted, is the most dangerous one because it would potentially give rise to a pandemic. To be clear, with a mortality of 53% and making due proportions with the Spanish flu, an estimated 380 million deaths worldwideimpressive numbers”.
The virus that causes bird flu is not just one. There was also talk of H7N9: what’s the difference?
“Also in this case there has been a passage from birds to mammals and mortality is still high, even if lower: we are talking about just under 2 mila cases reported for about 15 years now, with 700 dead and therefore one 40% mortality rate. But it is fair to remember that generally these micro-epidemics are linked to the attendance of live animal markets, in which there are many animals and especially birds, as happens in Asia. It is difficult to find similar contexts in Europe and, in particular, in Italy, where there is no tradition of markets so crowded with animals and, specifically, birds.
What are the measures to prevent the risk of a large-scale epidemic?
“The first is the check and the monitoring grasp of what is happening. For example, when they are found dead birds the causes must be investigated to understand whether they are consequences of the circulation of avian virus, especially in large farms. The second measure, where the avian influenza virus enters a farm, is theslaughter of infected animals. The third necessary action is the control of possibly subjects sick people, to understand the cause of the infection, whether it was an infection from a bird that was in turn sick due to the avian virus. It must also be said that today we have the necessary technology to develop any vaccines in the event of an epidemic”.
On a practical level, what should one pay attention to? Is there a risk of getting infected, for example by eating infected animal meat?
“In addition to the natural precaution of not touching or picking up dead or sick wild animals, we clarify that there are no risks in eating meat, such as chicken. The viruses that cause bird flu are extremely heat labile: cooking destroys them. I am other respiratory tract viruses, who live where the temperature is lower than the rest of the body. Greater precautions must be reserved for workers in the sector, such as veterinarians or employees of large farms, where the virus can be transmitted through animal secretions”.
What are the symptoms of a possible bird flu virus infection? How is it different from the one commonly found in the human species?
“Clinically there are no distinctions, because the symptoms are identical (fever, cough, sore throat, body aches, general malaise and tiredness, difficulty breathing up to pneumonia), but what should alarm is the severity of the disease, especially in younger subjects. However, there are diagnostic tests, which can be administered in particular and selected cases”.
When should I seek medical attention and how is bird flu treated?
“In the event, in fact, of particular seriousness, it is advisable to consult a doctor before going towards one pneumonia. The treatments available are those of the flu season, in addition to some antiviral drugs such as l’oseltamivir o lo zanamivir, for the type A flu virus, but they have a limit: they must be administered within the first three days, which is not always possible. In any case, I repeat, should a pandemic event break out, today we know how to behave both for the preparation of a vaccine and in the choice of drugs with which to treat the disease”.
Photo source: ANSA