Japan's National Institute of Infectious Diseases said authorities have found a new strain of the coronavirus in four passengers arriving from Brazil.
The new variant has similarities to strains found in the UK and South Africa, the NIID said in a statement on Sunday. The information about the new variant is limited to its genetic make-up, and it's difficult to immediately determine how infectious the strain is or the effectiveness of current vaccines against it, the institute said.
In a separate statement, Japan's Ministry of Health said the four passengers who arrived at Japan's Haneda airport from Brazil on Jan. 2 were later diagnosed with a variant of the virus. One male in his 40s, who was asymptomatic upon arrival, was hospitalized as his respiratory system worsened.
The NIID has informed the World Health Organization of the new strain, the Yomiuri Shimbun newspaper reported, adding the institute is investigating if the variant causes more severe cases.