TWO UK poultry workers have tested positive for avian influenza.

The pair were tested as part of routine screening following an avian influenza outbreak on the farm they worked on.

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They have not exhibited any symptoms of avian influenza and have since tested negative​​.

Despite detecting the virus in these workers, the UK Health Security Agency (UKHSA) has said the risk level to human health remains unchanged.

It added there had been no evidence of human-to-human transmission of the virus​​.

Routine screening

Detection of avian influenza in poultry workers can follow contamination of the nose and throat from breathing in material on the affected farm or can be a true infection.

It can be challenging to distinguish these in people who have no symptoms.

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.

In contrast, the UKHSA said it was more difficult for the second individual to determine which is the case.

Investigation

Further investigations are underway, but precautionary contact tracing has been undertaken for this second individual.

The World Health Organization reports that over the past 20 years, nearly 870 cases of human infection with the H5N1 virus have been reported across 21 countries.

The UKHSA said it was monitoring the situation closely and stressed that the risk to the general public remains low, with no signs of human-to-human transmission.

Monitoring

Professor Susan Hopkins, chief medical advisor at UKHSA, said: “Current evidence suggests that the avian influenza viruses we’re seeing circulating in birds around the world do not spread easily to people.

“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 Department for Environment, Food and Rural Affairs (Defra) advice about reporting.”