Blackbirds under threat from deadly Usutu disease: How you can help save them

ITV News Health and Science Correspondent Martin Stew reports on the virus infecting blackbirds across the UK

Blackbirds are one of the most popular and populous songbirds in the UK.

Around four million of them are now under threat from a deadly mosquito-borne virus.

Usutu, which was first detected in South Africa, spread to Europe in the mid-90s and arrived in London in 2020.

In the past four years, blackbird numbers in the city have fallen by 39%.

To map its spread, the British Trust for Ornithology has today launched the blackbirds in gardens survey, asking us all to record sightings.

You can take part in the survey here.

"It's really important to know what’s happening down south compared to the north in urban areas compared to the countryside," Hugh Hamner, from the British Trust for Ornithology, said.

"It all gives us a good idea of what is happening, why and what we can do about it."

Usutu doesn't appear to be a significant threat to other songbirds or humans. In Europe, blackbird numbers are recovering as natural immunity is built up.

Blackbirds are one of the most populous songbirds in the UK. Credit: PA

The bigger worry for scientists mapping the spread of mosquito-carried viruses is the precedent it sets for other diseases.

West Nile disease is a similar virus but can infect horses and humans - in rare cases causing death.

In The Netherlands, West Nile disease arrived four years after Usutu.

Government scientists from the Animal and Plant Health Agency (APHA) are now mapping the spread of mosquitos and sequences the genomes of viruses they carry to learn more about how best to prepare for the future.

Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know.