Spain has alerted the World Health Organisation of what it ‌believes to be a person-to-person transmission of the swine flu virus in its A(H1N1)v ‌variant.

The Catalan health department said the risk assessment for the population was considered "very low".

The person infected did not exhibit flu-like respiratory symptoms, it said, and tests on direct ‌contacts showed the ‌virus had ⁠not re-transmitted.

An earlier report by newspaper El Pais ​citing Catalan health department sources said the patient, who has since recovered, had no contact with pigs or pig farms, leading experts to conclude it was a human-to-human transmission of the pathogen.

This set off alarm bells ⁠due to the pandemic potential of ‌the ​swine flu virus if it re-combines with a human flu virus, which ​could happen ‌if a pig is infected with both at the same time, ​the El Pais report added.

The WHO did not immediately reply to a Reuters request for comment.

In 2023, the Netherlands notified ​the ​WHO of a confirmed human ​infection with a swine influenza A(H1N1)v ‌virus in an adult with no history of occupational exposure to animals.

In 2009, the swine flu pandemic in humans infected millions of people.

It was caused by a virus that contained genetic material from viruses ​that were circulating in pigs, birds and humans.