The first human case of swine flu (strain H1N2), similar to the virus that has been circulating among pigs, has been reported in the UK according to the UK Health Security Agency (UKHSA). 

The case was picked up during a routine surveillance in GP surgeries. 

The person, who is not known to have worked with pigs, suffered a mild illness and has made a full recovery.

The UKHSA said it is now carrying out contact tracing of close contacts to prevent further spread of the virus.

It is not known at this stage how transmissible the strain is or if there could be other cases in the UK.

The UKHSA also added it is too early to say if the strain could have pandemic potential.

There are around 50 reported cases worldwide of the H1N2 strain in humans.

First case human case of swine flu detected in UK

The case was detected as part of routine national flu surveillance undertaken by UKHSA and the Royal College of GPs, which was in place even before the Covid pandemic.

The patient was tested by their GP in North Yorkshire after experiencing respiratory symptoms.

This is Oxfordshire: The first human case of the flu strain H1N2 – which has been circulating in pigs – has been detected in the UK.The first human case of the flu strain H1N2 – which has been circulating in pigs – has been detected in the UK. (Image: Getty Images)

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.

The 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".

This was to "assist in the detection of cases and assessment of transmission, those people who are contacted and asked to test are encouraged to do so.”

Incident director at the UKHSA, Meera Chand, 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.

“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.

“Through our animal and human surveillance systems we work together to protect everyone.

“In this case we are providing specialist veterinary and scientific knowledge to support the UKHSA investigation.

“Pig-keepers must also report any suspicion of swine flu in their herds to their local vet immediately.”

What is Swine Flu? 

The NHS says swine flu is “a respiratory disease caused by a new strain of flu virus. The seasonal flu vaccines that are already available don’t protect against swine flu, so a new flu vaccine has been developed.”

Influenza A(H1) viruses are usually found in swine populations in most regions of the world, according to the UKHSA.

UKHSA adds: "When an influenza virus that normally circulates in swine is detected in a person, it is called a ‘variant influenza virus'.

"H1N1, H1N2 and H3N2 are major subtypes of swine influenza A viruses in pigs and occasionally infect humans, usually after direct or indirect exposure to pigs or contaminated environments."

In 2009, there was a pandemic in humans caused by swine flu (influenza A H1N1(pdm09)).

That virus, UKHSA says, contained genetic material from viruses that were circulating in pigs, birds and humans in the 1990s and 2000s.

It added: "Influenza A H1N1(pdm09) is now circulating in humans seasonally and is no longer referred to as swine flu. It is distinct from the viruses currently circulating in pigs."

This is Oxfordshire: In 2009, there was a pandemic in humans caused by swine flu (influenza A H1N1 (pdm09)).In 2009, there was a pandemic in humans caused by swine flu (influenza A H1N1 (pdm09)). (Image: Getty Images)

What are the symptoms of swine flu?

Swine flu symptoms, according to the NHS, include fever, tiredness, a cough and a sore throat.

Other symptoms can include a headache, aching muscles, chills, sneezing, a runny nose, loss of appetite.

You might also experience vomiting and diarrhoea.

Some people are at a higher risk of becoming seriously ill with swine flu, including pregnant women so it’s important to have the vaccine.