Officials are racing to track the contacts of the United Kingdom's first human case of a "distinct" form of swine flu.
On Monday, the U.K. Health Security Agency (UKHSA) announced it had detected a single confirmed human case of influenza A(H1N2)v as part of routine national flu surveillance.
There have been dozens of human cases of that strain reported globally since 2005, but none of them are genetically related to the recently identified case, officials said.
"Based on early information, the infection detected in the U.K. is a distinct clade (1b.1.1), which is different from recent human cases of influenza A(H1N2) elsewhere in the world but is similar to viruses in U.K. swine," reads the UKHSA's statement.