4 Omicron Types Likely Entered Japan Separately: Institute

Society Lifestyle

Tokyo, Feb. 15 (Jiji Press)--At least four different types of the dominant omicron coronavirus variant exist in Japan, and they are likely to have entered the country through separate routes, the National Institute of Infectious Diseases has said.

Of the four, three have spread across Japan, apparently causing the current nationwide surge in COVID-19 cases, according to the institute.

After conducting genome analyses of 2,650 cases registered by Jan. 17, the institute confirmed at least four types of the currently dominant BA.1 omicron strain that appear to have entered the country separately in or after mid-December last year.

The first type, similar to one found in Europe and detected widely in the Kansai western Japan region from late December, is no longer spreading thanks to "early detection and measures against cluster infections," the institute said.

The second type is prevalent in Japan and is similar to or the same as a type found widely in the United States.

[Copyright The Jiji Press, Ltd.]

Jiji Press