A top scientist is calling on governments to start investing in vaccines against all strains of flu circulating among birds and mammals in case the disease spreads to humans.
Sir Jeremy Farrar, who is set to become chief scientist at the World Health Organisation (WHO), said there is already evidence that bird flu has been contracted and spread by mammals, such as minks and seals.
While transmission of avian flu to humans is rare, having only occurred a small number of times in the UK, the fact it has spread to some mammals increasings the risk it could eventually be passed onto people.
There are many different strains of bird flu virus and most do not infect humans, but the NHS warns there are four strains that have sparked concern in recent years. These include H5N1, H7N9, H5N6 and H5N8.
The NHS says that while H5N1, H7N9 and H5N6 do not infect people easily and are not usually spread from human to human, several people have been infected around the world, which has led to several deaths. In February 2021 H5N8 was found to have infected a small number of people for the first time, in Russia.
Speaking at a press conference at the Wellcome Trust on Monday (20 February), Mr Fararr said vaccines against bird flu should be developed. He said: “What I would like to see [and am] pushing for is that we continue what we do with our seasonal influenza [vaccines], and that governments invest in having vaccines for every single other strain of influenza that exists in the animal kingdom through at least phase one and phase two studies, so you know that they’re safe and they’re immunogenic and you know you can manufacture them.”
Mr Farrar went on to say there is “not an unlimited number of influenza strains” circulating among animals, which means it is possible to develop vaccines against all of them. He explained: “If I was worried about my security, that is what I would be doing — to make sure we have those vaccines, a route to regulation, a route to manufacturing. If there were an H5N1 outbreak, we would at least know that we had vaccines available which are safe.
“I would task the industry to say: ‘We want as an insurance policy vaccines against all of these and want them at a stage where we could move to global manufacturing if something happened’.” When asked if there was evidence of mammal-to-mammal transmission of bird flu, Mr Farrar said it is his understanding “that it is spreading.”
Lessons to be learned from Covid
The call for a bird flu vaccine comes as experts have expressed concern about how far across the world the disease is spreading and say its spread should be closely monitored.
Avian influenza has been detected as far away as South America and the virus has also killed mammals such as sea lions, mink, foxes and otters. It is infecting wild bird populations across the globe and could potentially infect some species, perhaps even endangered ones, that have never before been in contact with the flu, creating uncertainty about how they will react to the virus.
Professor Ian Brown, head of virology at the Animal and Plant Health Agency (APHA), told a virtual Science Media Centre press briefing: “I think it is really quite a worry that the virus has already reached so far down into South America. And we have to consider that there are definitely risks for biodiversity in terms of Antarctica.”
Professor Martin Beer, head of the Institute of Diagnostic Virology at the Friedrich Loeffler Institute in Germany, added: “This is a point which is also worrying me most at the moment that it’s reaching areas where this type of virus has never been. And we are talking about a whole continent with a lot of different bird species which never had contact with this kind of virus.” The virus has been detected in North and South America and so far only Africa and Australia have been spared.
Prof Brown said it is important to closely monitor the spread of bird flu, and mutations in the virus, and learn lessons from the Covid-19 pandemic.
He added: “Have we got good systems that are globally set up to track and monitor those concerning events fast? If this virus was to ever, heaven forbid, jump to humans, we need to have done that basic work in the animal and bird sector.
“So it is about global responsiveness here and working together globally to make sure we can track this virus very fast and understand what it’s doing. My biggest concern is have we got that global structure… have we learnt all the lessons from Covid?”