As coronavirus mutates, countries scramble to put up defenses

As coronavirus mutates, countries scramble to put up defenses

Brazil variant joins UK and South African forms confronting authorities from Asia to US

TOKYO — First identified in the U.K. late last year, a new variant of the virus that causes COVID-19 has now been confirmed in 49 countries and regions. A separate variant first found in South Africa has been spotted in 19 countries.

Japan has found another new variant, one that is thought to have come from Brazil.

The emergence of new and likely more infectious variants has set off alarm bells around the world about the risk of dangerous mutations as the pandemic drags on.

University of Tokyo professor Yuichi Iino warns that the U.K. variant, which data shows is up to 70% more infectious than the main form, can spread rapidly.

According to Iino’s model, if the starting point were 300 carriers of the main form of the virus and 10 of the U.K. variant, there would be around 1,000 new infections in four months. That would quickly expand to 2,000 in six months, at which point the U.K. variant would overtake the main form.