Bird flu: Expert calls for work to start on vaccine with risk to humans 'increasing'
The virus has already jumped from birds to otters and foxes, and the World Health Organization is warning against complacency in the face of H5N1.
Work should start to create a vaccine against bird flu in case the virus starts to spread between humans, a UK expert has warned.
Professor Ian Brown, head of virology at the Animal and Plant Health Agency, said the rapidly evolving virus was increasingly spreading from birds into mammal species, raising the threat to humans.
"Any spillover event [to other species] on the scale we are seeing increases the risk," he said.
"We know from COVID that pandemic preparation takes time, to get vaccines, antivirals and therapeutics.
"We don't have H5 vaccines ready to vaccinate people.
"We should start the process."
His rallying cry echoed an earlier warning against complacency from the World Health Organization (WHO).
Dr Tedros Adhanom Ghebreyesus, WHO's director-general, said on Thursday that while the current risk to humans is low "we cannot assume that will remain the case and we must prepare for any change in the status quo".
Until recently the H5N1 virus largely infected poultry and migratory birds, including in the UK.
But over the past two years it has become established in many wild bird populations and has started to infect mammals, including farmed mink in Spain, wild sealions in Peru and, sporadically, foxes and otters in the UK.
"The virus is changing faster than we can characterise it," said Professor Martin Beer, head of the Institute for Diagnostic Virology at the Friedrich Loeffler Institute in Germany.
Bird flu has jumped to mammals - so how worried should humans be?
Prof Brown agreed, warning that while there is so far no evidence of the virus spreading between mammals, it needs to be tracked carefully to monitor the effect of new mutations."
"It's a numbers game," he said. "There has been a step-change in the spread of infection.
"We should not sit idle, because we know what happened with COVID."
According to the WHO, 868 people have been infected with H5N1 over the past two decades, with 457 deaths. There has so far been no documented human-to-human transmission.
Prof Brown said the groundwork for vaccines should start now, but they could only be finalised when a specific viral strain was known to be spreading in humans.
-sky news