Japan confirmed its first two cases of COVID-19's mu variant, designated by the World Heath Organization as a variant of interest, in June and July during airport screenings, the Japan Times reported on Thursday, quoting the health ministry. The ministry said Wednesday night that it detected the variant in a woman in her 40s who arrived on June 26 from the United Arab Emirates. Another woman in her 50s who arrived in Japan on July 5 from the U.K. also had the mu variant, it said. The two women were asymptomatic. Not much has been confirmed about the mu variant, also known as B.1.621, including how transmissible it is or whether it can evade vaccine protections. "The mu variant has a constellation of mutations that indicate potential properties of immune escape," the WHO said in a statement. The strain was first detected in Colombia in January, and it makes up about 40% of cases in the country, according to the WHO. As of Wednesday, the strain had been detected in at least 40 countries.
