The UK’s first human case of swine flu strain H1N2, very similar to what has been circulating in pigs, has been detected in North Yorkshire.
The person involved went to their GP in North Yorkshire with respiratory symptoms and is not known to have worked with pigs.
They have fully recovered.
Routine surveillance of doctor’s surgeries picked up the case after the person suffered a mild illness.
The source of the infection remains unknown and under investigation.
It is not known at this stage how transmissible the strain is or if there could be other cases in the UK.
It is also too early to say if the strain could have pandemic potential.
The UK Health Security Agency (UKHSA) said it was “monitoring the situation closely and is taking steps to increase surveillance within existing programmes involving GP surgeries and hospitals in parts of North Yorkshire.”
Close contacts of the person involved are being followed up by the UKHSA and its partner organisations and people have been urged to test if asked to do so to help with the detection of cases.
They will also be advised on further care if they have symptoms or test positive.
The UKHSA has notified the World Health Organisation (WHO) of the latest case.
There have been about 50 reported human cases worldwide of the H1N2 virus since 2005, none of them related genetically to this strain.
The patient was tested by their GP in North Yorkshire after experiencing respiratory symptoms. The strain was identified via polymerase chain reaction (PCR) testing and genome sequencing.
The UKHSA said people with respiratory symptoms should continue to follow the existing guidance – avoiding contact with other people while suffering symptoms and taking particular care around vulnerable people and the elderly.
Meera Chand, incident director at the UKHSA, said: “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.
“We are working rapidly to trace close contacts and reduce any potential spread.
“In accordance with established protocols, investigations are under way to learn how the individual acquired the infection and to assess whether there are any further associated cases.”
Chief veterinary officer, Christine Middlemiss, said: “We know that some diseases of animals can be transferred to humans, which is why high standards of animal health, welfare and biosecurity are so important.
“Pig-keepers must also report any suspicion of swine flu in their herds to their local vet immediately.”
H1N1, H1N2 and H3N2 are major subtypes of swine flu A viruses in pigs and occasionally infect humans.
Based on early information, the UKHSA said the strain detected in the UK differs from recent human cases of H1N2 elsewhere in the world, but is similar to viruses in UK pigs.
In 2009, there was a pandemic in humans caused by flu strain H1N1, commonly referred to as swine flu.
This now circulates in humans seasonally.