We are still “a long way” from being in a situation where bird flu could infect humans and spread in a similar way to Covid-19, an expert from the UK’s Animal and Plant Health Agency (Apha) has said.
Scientific director Professor Ian Brown was speaking after it emerged otters and foxes have been found in the UK with avian flu.
The animals are believed to have eaten dead wild birds that were infected with the virus. However, health officials have said the risk to humans is low.
The UK Health Security Agency (UKHSA) said in December it had been told by Apha that 20 mammals had been tested in the UK, of which eight (foxes and otters) were positive for avian flu. This figure has since been updated to nine.
Prof Brown told BBC Radio 4’s Today programme there was evidence the flu had now jumped to other species.
“We’ve recently detected events both here and around the world, evidence that this virus can on certain occasions jump into other species. To be clear, though, this is still a bird virus essentially, that wants to be in birds,” he said.
“These are wild mammals, animals that scavenge on sick and dead birds, and there’s a lot of dead wild birds at the moment due to the bird flu presence around the globe.
“Those animals are consuming and being exposed to very high quantities of virus, and that’s leading to some spillover infection.
“What we don’t have any evidence of is that it can then go from fox to fox or otter to otter, so these are what we call dead-end infections.”
Asked about potential spread to humans, Prof Brown said: “We need to understand the consequence of this infection. Does it make the virus change by jumping its host? We’re aware those events can sometimes lead to that.”
Asked if there was a possibility bird flu could become a virus that infects humans, like Covid-19, he said: “At the moment, we’re a long way from that. We’ve seen this jump, we’ve not seen maintenance in a mammalian species and we haven’t seen a succession of changes in the virus that tell us it’s moving more towards a virus that can infect humans.
“This still is a spillover, but we need to be watchful.”