University of Tokyo economists estimate the capital could take an additional ¥4 trillion economic hit if highly contagious coronavirus variants spread quickly across the city, but say the impact can be mitigated if infections are slowed.

A relatively speedy spread of mutations in Tokyo could leave the capital dealing with over 1,400 daily infections in May — up from around 500 in recent days — an increase that would make variants a major source of new COVID-19 infections by around July, the estimate shows.

Such a scenario would expand the economic loss in Tokyo by ¥3.76 trillion, according to the team led by Taisuke Nakata, an associate professor of economics, and Daisuke Fujii, an assistant professor of economics.

In a less severe scenario in which the spread of variants is slower, the team estimates Tokyo would sustain a more than ¥2 trillion hit.

In that case, the number of COVID-19 cases would top 1,000 in May but the variants would not make up the majority of infections until around the end of the year.