A person in North Yorkshire has tested positive for a strain of flu that is similar to a virus circulating in pigs, according to the UK Health Security Agency (UKHSA).
This is the first time that this virus has been detected in humans in the UK.
Here is what you need to know:
What is the virus?
The virus is called influenza A(H1N2)v and it is similar to a strain of flu that is currently circulating in pigs in the UK.
What do we know about the first case?
A person in North Yorkshire visited their GP with breathing problems and was diagnosed with the illness as part of routine national flu surveillance.
It is unknown how they contracted the virus and they are not known to have had contact with pigs.
The individual had a mild illness and has since fully recovered.
Close contacts of the case are being monitored by UKHSA and will be offered testing and treatment if they test positive.
Have there been cases in other parts of the world?
There have been 50 human cases of A(H1N2)v reported globally since 2005, but none of them have been this exact strain.
The UKHSA states that this strain is a “distinct clade” that is different from other human cases reported worldwide, but similar to viruses found in UK pigs.
An 18-year-old in the US was diagnosed with A(H1N2)v in August after being in contact with pigs at an agricultural fair, but no other cases were reported and there was no human-to-human transmission.
Is this swine flu? Bird flu? Both?
This virus is not the same as H1N1, which caused the 2009 swine flu pandemic.
H1N1 contained genetic material from viruses that were circulating in pigs, birds, and humans in the past, but it is now referred to as seasonal flu in humans and is different from the viruses currently circulating in pigs.
A(H1N2)v is a subtype of the influenza A virus and normally circulates within its specific species, including humans, birds, and pigs.
According to the World Health Organization, animal influenza viruses are distinct from human influenza viruses and do not easily transmit to and among humans.
A(H1N2)v is not linked to birds. The current dominant bird flu strain is H5N1, which has spread to mammals.
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What happens now?
UKHSA is closely monitoring the situation and plans to increase flu surveillance in parts of North Yorkshire.
The agency is also investigating how the person contracted the virus and has notified the WHO of the latest case.
What should I do if I have symptoms?
If you have respiratory symptoms, the UKHSA advises avoiding contact with other people, especially older individuals or those with existing medical conditions.