Please see the corrected advisory below. The California Department of Public Health mask mandate is in effect until January 15, 2022.
The first cases of illness caused by SARS-CoV-2 Omicron variant have been identified in the last week in Orange County, including at least one case that was acquired locally. Omicron case counts are rising in Southern California and around the country. Omicron has been shown to be very efficient at transmission with a doubling time of ~2-3 days compared to ~14 days for the Delta variant.
Omicron will likely soon become the dominant variant in our county, but the delta variant is still present as well. In the coming weeks, it will be critical to perform whole genome sequencing (WGS), particularly for hospitalized patients, to determine the burden of serious disease being caused by the different variants and the effectiveness of vaccination and treatment.