XBB.1.5 is the most transmissible Omicron subvariant that has been detected so far

Countries should consider recommending passengers wear masks on long-haul flights to counter the latest Omicron subvariant given its rapid spread in the United States, World Health Organization (WHO) officials said on Tuesday.

In Europe, the XBB.1.5 subvariant of the virus that causes COVID-19 is being detected in small but growing numbers, WHO/Europe officials said at a press briefing.

Passengers should be advised to wear masks in high-risk settings such as long-haul flights, said WHO's senior emergency officer for Europe, Catherine Smallwood, adding: "This should be a recommendation issued to passengers arriving from anywhere where there is widespread COVID-19 transmission."