However, the source of their infection is still unknown and is currently under investigation. UKHSA, along with partner organizations, is closely monitoring and following up with close contacts of the case. The contacts of the person will be tested if necessary. The UK Health Security Agency has advised individuals experiencing respiratory symptoms to adhere to guidelines, which include avoiding contact with others, especially the elderly or those with pre-existing medical conditions, until symptoms subside.
To enhance the detection of cases and evaluate transmission, UKHSA is increasing surveillance efforts. Meera Chand, Incident Director at UKHSA, said: “It is thanks to routine flu surveillance and genome sequencing that we have been able to detect this virus. This is the first time we have detected this virus in humans in the UK, though it is very similar to viruses that have been detected in pigs.”
Investigations are underway to learn how the individual acquired the infection and to assess whether there are any further associated cases, she said.
Influenza A(H1) viruses are enzootic in swine populations in most regions of the world. When an influenza virus that normally circulates in swine is detected in a person, it is called a ‘variant influenza virus’. Swine influenza A viruses, including H1N1, H1N2, and H3N2, are the main subtypes in pigs and occasionally infect humans through direct or indirect exposure to pigs or contaminated environments.
According to UK Health Security Agency, there have been a total of 50 human cases of influenza A(H1N2)v reported globally since 2005; but influenza A(H1N2)v has not previously been detected in humans in the UK.