Table 1. PCR tests conducted for N501Y and L452R mutation screening and COVID-19 cases reported by region, Japan, March to September 2021.

Region	N501Y			L452R
	8 March to 17 May 2021			7 June to 20 September 2021
	A) Number of variant screening tests performed	B) Number of COVID-19 cases reported	A) to B) ratio	A) Number of variant screening tests performed	B) Number of COVID-19 cases reported	A) to B) ratio
Hokkaido	1955	11 302	17.3	6186	20 258	30.5
Tohoku	549	10 428	5.3	1896	19 351	9.8
Kanto-Koshin	19 369	81 471	23.8	183 315	477 227	38.4
Hokuriku	130	4187	3.1	860	13 053	6.6
Tokai	2157	21 987	9.8	14 038	90 442	15.5
Kinki	10 108	80 016	12.6	29 639	165 811	17.9
Chugoku	1023	8708	11.7	3293	22 470	14.7
Shikoku	232	4006	5.8	495	8915	5.6
Kyushu	1606	20 255	7.9	8496	65 259	13.0
Okinawa	694	5602	12.4	3565	30 322	11.8
Japan	37 823	247 962	15.3	251 783	913 108	23.6