Two people suspected of contracting bird flu from a poultry farm in England did not spread the virus to other people, an official investigation has found.

Contact tracing was carried out for both cases but all close contacts tested negative, the UK Health Security Agency said.

Neither person experienced symptoms and they have both since tested negative.

The findings confirm there is still no evidence of human-to-human transmission of the H5N1 strain of avian influenza, which is highly infectious in wild birds and poultry and has led to the deaths of millions of birds worldwide since autumn 2021.

The UKHSA says the risk to human health remains at level 3, which means there is evidence of changes in the virus genome that could make infection in mammals more likely, but the risk to humans is low.

There have been no confirmed bird flu infections in mammals since March.

The two poultry workers were the first cases in people in the UK for nearly 18 months. There have only been a total of 10 cases in people of the H5N1 strain since the outbreak began.

They were detected following a pilot screening programme of poultry workers at farms with bird flu outbreaks in England.

A total of 85 poultry workers have been tested for bird flu since March, with only the two cases detected.

The first person did not appear to have a sustained infection, and only traces of the virus were found in their nose and throat, which could have occurred due to environmental contamination. Close contacts were observed for any symptoms, but none occurred.

The second person showed results that were “compatible with infection” but they remained asymptomatic throughout, the UKHSA said. Twenty contacts were identified and 15 of these were tested, all of whom were negative. All remained asymptomatic.

Dr Meera Chand, deputy director at UKHSA, said: “The evidence suggests that the avian influenza viruses we’re seeing circulating in birds around the world do not spread easily to people. Globally, there is no evidence of human-to-human transmission having occurred.

“However, viruses evolve all the time and UKHSA continues to closely monitor the situation for any evidence of changing risk to the public, including through our surveillance of people who have come into contact with infected poultry. Our latest risk assessment shows that the risk to the general public remains very low.”

By admin