Virologist Wendy Barclay: “Wild avian viruses mix their genetics all the time. It’s like viral sex on steroids’ | Infectious diseases

WEndy Barclay is a leading British virologist and head of the Department of Infectious Diseases and President of Medical Research in force of the Imperial College of London. Expert in pathogenesis and the transmissibility of influenza viruses, she sat on the scientific advisory group for emergencies (SAGE) and the Consultative Group of threats of new and emerging respiratory viruses (Nervtag) during the coco-19 pandemic, providing Advice on the risks posed by coronavirus and appropriate medical countermeasures.

What prompted you to study virology?
After obtaining my Cambridge diploma with a diploma in natural sciences, I thought I could find a job with a pharmaceutical company. Then, I saw that the common common unit of Salisbury was looking for a doctorate to work on rhinovirus, the viruses that cause colds. I had not studied viruses before, but the same year – 1988 – the first crystalline structure of a virus was published and it was a rhinovirus. The common cold unit was a steep learning curve.

Were there times when it was difficult to be a woman working in virology?
Yes. There is a famous story of “Téapot Silver” that I tell about my time as a junior speaker, where I was always trained to interview panels as a symbolic woman. On an occasion, the dean of chemistry turned to me and said: “I will take mine with milk and two sugars.” The other men in the room fell out of embarrassment and jump forward to pour the tea before power. I think it is important that women working in science have female models. I am head of the Imperial department and I am proud to say that I have recruited several young teachers, who are all excellent. I firmly believe that it is because they can see that the imperial is a place where women can prosper and become leaders.

Tell us about your research on H5N1 bird flu. What does the virus keep scientists at night?
Bird flu viruses are circulating all the time. The H5N1 subtype which arouses so much concerns at the moment infected humans for the first time in 1997, but although he caused a serious illness, he never took off in pandemic. Then, he withdrew into the population of wild birds, but he has never really disappeared: we saw generalized epidemics in poultry, with human cases, in the early 2000s. Then, in 2014, He raised his head again. The problem is that these wild avian viruses mix their genetics all the time. It’s like viral sex on steroids. At some point, they offer a solution that improves their physical form and their ability to infect new hosts.

So what’s going on now?
In 2020, a new H5N1 variant, known as Clade 2.3.4.4b, emerged. The wild birds distribute it in huge areas and have done what the flu is always doing in wild birds, it mixed its genome. Some strains have also infected a wide range of mammals, including cows. There, it seems to be very concentrated in the bets and mammary glands and when you plunge another cow on the same milking machine, it transfers from one cow to another. The flu has not been reported before in the cows and the virus reproduces so well in them that we suspect that between the birds and settle in these herds, the virus must have undergone adaptive mutations.

I think you have just disseminated a new pre-print document (research document project) describing some of these changes.
Yes, I directed a consortium of influenza virologists based in the United Kingdom by looking for how the virus evolves. In a recent study, we have identified two key mutations that allowed the virus to reproduce more effectively within the cells of infected cattle. What is worrying is that the same mutations also allow the virus to reproduce better in pig and human cells, which means that it has come closer to the adaptation of humans. We also found that the Viruses of the 2.3.4.4.4B viruses picked up a different Neuraminidase gene (N in H5N1) that older viruses of the early 2000s. The new N helps the virus to cut more effectively the human mucus And more easily targets cells in the nose and throat. It is still one more block than the viruses of the Clade 2.3.4.4b have overcome become adapted human.

So, to what extent should we be concerned?
Whenever the bird flu is puts in mammals, it undergoes mutations that can bring it closer to being the type of virus that can spread between humans. To date, we have seen 66 confirmed cases and eight probable human cases of the H5N1 virus of Clade 2.3.4.4b in the United States. Two of them, one in British Columbia, the other in Louisiana, caused serious illnesses. Earlier this month, Louisiana’s patient died.

Does that mean that we should expect a pandemic from H5N1?
Not necessarily. The virus is able to reproduce within human cells but has not acquired the set of mutations in the HA gene (H5N1) required to transmit between people in the air. According to the Laboratory Studies of the flu, we know that, to transmit, the virus must pass to use a human receiver, but the switching of the receivers is not enough for itself to support airborne transmission. You need a second change that makes the h more stable in difficult environments such as the droplets we expire from our respiratory tract. We have not yet seen proof of this, or in people, cows or animals in the wild.

To what extent are we prepared for a pandemic of bird flu? What if the next pandemic was triggered by a “x disease”, a pathogen unknown to science?
The good news is that the World Health Organization has followed the pace of the evolution of the bird flu virus and that we have stumps of vaccine seeds which could be used to do a lot of vaccination in the event of an epidemic . We also tried and tested approved antiviral drugs, such as Tamiflu and Relenza. And thanks to the technology of mRNA vaccines, pharmaceutical companies are also much better for making vaccines against a new virus, including a new influenza or another new coronavirus.

If there was a pandemic of bird flu and we had to use locks, do you think that people would be as conforming as before?
No, I think they would have trouble. If there is a reversal of two to three days to get a diagnosis and people must miss the work when they need to earn money, it is naturally a very difficult decision. But one of the great things we have learned during the cocvid is that people are able to use diagnostic kits at home – listen to the nose and throat to test the infection. Maybe I have an optimistic vision of humanity, but my vision is for a test in everyone’s bathroom cabinet. Then, when you hear a new virus spreads, you can make a socially responsible decision to test and go out or not.