The variant has been identified as a super-spreader and has led to the lockdowns of five cities , , , and , an area which accounts for almost two-thirds of the country's population.
It was not detected again until September when it reappeared among samples in California, but numbers remained very low until November.
In Japan, cases of R.
If a second variant is 50% more transmissible, that number would be 50% higher.
The median of the R 0 mean estimate for the ongoing epidemic overall is 1.
In an interview on 28 April, he said: This is something where we're still gaining data daily.