08/09/2021: Lab Advisory: SARS-CoV-2 Variant Classification Updates

CDC's Laboratory Outreach Communication System (LOCS)

Audience: Individuals Performing COVID-19 Testing

Level: Laboratory Advisory

On August 3, 2021, CDC began reporting the proportions for each of the lineages that are collectively designated as the Delta variant. These include B.1.617.2, AY.1, AY.2, and AY.3. Prior to August 3, CDC aggregated the proportions of the sub-lineages AY.1, AY.2, and AY.3 with B.1.617.2, which is the parental Delta lineage.

CDC and the World Health Organization classify the parental lineage (B.1.617.2) and all three sub-lineages (AY.1, AY.2, and AY.3) as Variants of Concern.

For more information, please visit the SARS-CoV-2 Variant Classifications and Definitions page and the COVID Data Tracker.

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Thank you,

The Laboratory Outreach Communication System

Laboratory Outreach Communication System (LOCS) | Division of Laboratory Systems (DLS)

Center for Surveillance, Epidemiology, and Laboratory Services (CSELS)

Centers for Disease Control and Prevention (CDC)