UK detects H5N1 avian influenza in additional individuals
Starting in March 2023, a program was initiated to monitor individuals who had been exposed to avian influenza but showed no symptoms. As of July 10, 2023, a total of 144 individuals from 8 infected locations were tested, resulting in 4 positive cases (2.7% positivity rate). This indicates an increase of 2 new detections since the previous briefing.
Since 2021, there have been a total of 5 cases of human influenza A(H5N1) detected in the UK, with one of them identified in December 2021 during a surveillance pilot.
The 2 recent detections were found in individuals who had been exposed at 2 different locations where previous detections had already been reported. These detections are now linked to one backyard flock (in 2021) and 3 infected locations (as part of the 2023 surveillance program).
Globally, since December 2021, there have been 15 officially reported human cases of influenza A(H5N1). Out of these cases, 12 belong to the clade 2.3.4.4b. This includes the 2 new detections in England since the last briefing. There is no evidence to suggest human-to-human transmission from these cases.
