COVID-19 Variant Dashboard

Last content update: 10/21/2021

COVID-19 Variant Report

This dashboard provides the cumulative count of COVID-19 variants that have been identified and reported in Santa Clara County to date.

Since the start of the pandemic, multiple variants of SARS-CoV-2 have appeared. Most do not have significant health impacts, but some may affect COVID-19 transmission, disease severity, testing, treatment, or vaccine effectiveness. The Delta variant has been the predominant variant since July, accounting for the vast majority of COVID-19 cases locally and nationally. Vaccine effectiveness and variants continue to be monitored and studied nationally and globally. For information on vaccinations in Santa Clara County please visit our vaccination dashboard

Santa Clara County follows the CDC SARS-CoV-2 classification scheme and definitions, which includes four classes of SARS-CoV-2 variants:

  • Variant of High Consequence (VOHC) is used to describe a variant for which there is clear evidence that public health and medical countermeasures have knowingly reduced effectiveness. To date, there have been no VOHC identified in the United States.
  • Variant of Concern (VOC) is used to describe a variant that has already been found to have a significant impact on health, such as being more contagious, more likely to cause severe illness, or less responsive to vaccines or treatment.
  • Variant of Interest (VOI) is used to describe a newly emerging variant which has been associated with significant genetic changes and may require appropriate public health actions. There are currently no designated VOI.
  • Variant Being Monitored (VBM) is used to describe all variants with substitutions of concern, including previous VOIs and VOCs, in the United States that are currently being monitored by the CDC to learn more about their public health impact, but are not thought to pose a significant or impending risk to the public.

As CDC and others discover and designate new variants, they will be added to this dashboard. As more information becomes known about particular variants, their designations may change.

Known Variants of High Consequence in Santa Clara County



Known Variants of Concern in Santa Clara County

Variant WHO Label Number of Cases by Variant
B.1.617.2* Delta 7,657

*Includes all AY sublineages

Known Variants of Interest in Santa Clara County


Known Variants Being Monitored in Santa Clara County

Variant WHO Label Number of Cases Caused by Variant
B.1.1.7* Alpha 796
B.1.351* Beta 25
P.1* Gamma 155
B.1.525 Eta 5
B.1.526 lota 66
B.1.617.1 Kappa 24
B.1.617.3 - 1
B.1.621* Mu  51
P.2 Zeta  4

*Includes all sublineages (Q for B.1.1.7; B.1.351.2/B.1.351.3 for B.1.351; P.1.1/P.1.2 for P.1; B.1.621.1 for B.1.621) 


Other Variants in Santa Clara County

Variant WHO Label Number of Cases Caused by Variant
C.37 Lambda 8


This dashboard is updated every Thursday using data from the previous Monday (October 18, 2021), but please note that there is a lag in the data of up to a month or more due to the time required for laboratories to sequence and report variant cases to the Public Health Department.

Source: California Reportable Disease Information Exchange; the County of Santa Clara Public Health Department receives notification of case reports determined to be variants of interest/concern from multiple sources including routine genomic surveillance conducted through County of Santa Clara Public Health Lab, the California Department of Public Health, academic partners, and commercial laboratories.

Data included in this dashboard only represent cases reported or known to the County of Santa Clara Public Health Department. As a result, variant case counts presented in this dashboard do not represent the total number of infections due to variant strains that may be circulating in Santa Clara County. Cases reported in this dashboard are preliminary and are subject to change upon further investigation. The Epsilon Variants Being Monitored (B.1.427 and B.1.429), which number more than 2,000 in Santa Clara County, are not included in this dashboard at this time.

For more information on which variants the California Department of Public Health (CDPH) is tracking and on the number of cases per variant reported across California, see the CDPH website on Tracking Variants.

Where to find more Information

Click here to return to main COVID-19 Data and Reports page

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