Omicron Variant in Orange County
December 21, 2021
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.
Recommendations for Providers
  • OCHCA requests that the following SARS-CoV-2 positive specimens be submitted to the OCHCA Laboratory for whole genome sequencing:
  • All patients hospitalized with SARS-CoV-2 infection
  • All cases associated with congregate living settings such as skilled nursing facilities and homeless shelters
  • Cases associated with unusual circumstances such as large outbreaks
  • Positive cases who traveled internationally in the last 14-days or had exposure to persons with recent international travel
  • For persons infected with the Omicron variant, the recommendations and mandates for isolation and quarantine including those of the County Health Orders are unchanged from standards for all COVID-19 cases.
  • All eligible persons should be vaccinated including receiving a booster dose according to CDC recommendations. Health care workers in particular should receive boosters as indicated to protect against illness, given the increased risk of exposure at home and in the workplace in the coming weeks.
  • Providers should be aware of a recent change in CDC’s Interim Clinical Consideration for the Use of COVID-19 Vaccines which now states a preference for the use of mRNA vaccines (Pfizer- BioNTech & Moderna) over the use of the Johnson & Johnson/Janssen vaccine.  
Guidance for the Public

For questions or concerns, please contact the Communicable Disease Control Division at 714-834-8180.
If you do not currently receive our Provider Advisories, you can add yourself to our email list via the button below.