Bird flu has been detected in two poultry workers in the UK, it has been confirmed. 

The UK Health Security Agency (UKHSA) said it had detected the Influenza A (H5) virus in two employees in England but that there were no signs of human-to-human transmission.

It follows the introduction of an asymptomatic testing programme for people who have been in contact with infected birds.

A highly pathogenic variant of avian influenza (HPAI) H5N1 has killed tens of thousands of wild birds across the UK over the past two years. 

The two people returning positive tests are known to have recently worked on an infected poultry farm in England.

Neither has experienced any symptoms of avian influenza and both have since tested negative.

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The UKHSA said, based on the timing of exposures and test results, one individual is likely to have had contamination of the nose and/or throat from material inhaled on the farm, whilst for the second individual it is more difficult to determine which is the case.

Further investigation is underway but, meanwhile, precautionary contact tracing has been undertaken for this second individual, the statement said.

Professor Susan Hopkins, chief medical adviser at UKHSA, said it was crucial the public did not touch dead birds. 

“Current evidence suggests that the avian influenza viruses we’re seeing circulating in birds around the world do not spread easily to people," she said. 

“However, we know already that the virus can spread to people following close contact with infected birds and this is why, through screening programmes like this one, we are monitoring people who have been exposed to learn more about this risk.

“Globally, there is no evidence of spread of this strain from person to person, but we know that viruses evolve all the time and we remain vigilant for any evidence of changing risk to the population.

“It remains critical that people avoid touching sick or dead birds, and that they follow the Defra advice about reporting.”