From BBC
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BBC climate and science team
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A mosquito-borne disease freshly arrived in Britain has spread large distances, with scientists racing to understand the risks to wild birds.
Infected insects can spread the deadly Usutu virus to blackbirds, raising fears for the famous songsters.
New data shows Usutu has spread across much of southern England in five years, and has been linked to declines in some blackbird populations.
Scientists are monitoring its spread amid warnings that mosquitoes and the diseases they carry may expand their range under climate change.
“We’ve seen that the virus has spread further than we thought it might do, and it’s persisted,” Dr Arran Folly of the Animal and Plant Health Agency (APHA) told the BBC.
Scientists at the APHA in Weybridge, Surrey, have been tracking mosquito-borne diseases in wild birds for decades, amid warnings that climate change is turning Europe into a potential breeding ground for the insects.
Longer summers, hotter temperatures and heavy rainfall are creating conditions for the nuisance insects to move into areas that were previously inhospitable to them.
Until 2020, all results came back clear. Then, after the summer heatwave of that year, Usutu was detected in several blackbirds in Greater London.
“Blackbirds specifically are quite susceptible to the virus and since 2020 we’ve found a decline in blackbirds of approximately 40% in Greater London,” said Dr Folly.
“It gives an indication that in the future we might get other viruses that are transmitted by mosquitoes emerging in the
