Table 1.

For each week, table shows the total number of cases for the whole Catalan system, the number of samples screened, and the number and rate of omicron detected.

Week	Overall cases	N samples	Omicron samples	%	95% CI
49/2021	17,742	349	5	1.4	[0.5–3.3]
50/2021	24,207	600	150	25.0	[21.6–28.7]
51/2021	41,682	739	408	55.2	[51.5–58.8]
52/2021	90,500	640	543	84.8	[81.8–87.5]
01/2022	145,349	653	617	94.5	[92.4–96.1]
02/2022	167,785	632	624	98.7	[97.5–99.5]
03/2022	220,146	425	425	100.0	[99.1–100.0]

Samples were collected from primary care cases in the hospital's area of influence and first analyzed with TaqPathTM COVID-19 RT-PCR Kit with SGTF as a source of rapid identification. Ratios were later confirmed with whole-genome sequencing techniques.