Skip Navigation LinksAFL-21-24

State of Cal Logo

State of California—Health and Human Services Agency
California Department of Public Health

AFL 21-24 (Rescinded)
July 22, 2021

General Acute Care Hospitals
Acute Psychiatric Hospitals

Call for Specimens from Hospitalized Coronavirus Disease 2019 (COVID-19) Patients

​NOTE: This AFL has been temporarily rescinded and is not in effect until further notice. Please check back again for updates.  

All Facilities Letter (AFL) Summary

This AFL has been temporarily rescinded and is not in effect until further notice. Please check back again for updates.  

This AFL announces a request that facilities submit respiratory and/or serum specimens from hospitalized COVID-19 patients to assist the state in tracking COVID-19 variants. Specimens can be submitted to your local public health laboratory or to California Department of Public Health's (CDPH) Viral and Rickettsial Disease Laboratory (VRDL).

Over the course of the COVID-19 pandemic, there have been additional variants of the SARS-CoV-2 virus that causes COVID-19 identified in California. While there is much to be learned about these variants, evidence continues to grow that virus mutations can affect transmission, diagnostics, therapeutics, clinical outcome, and immune escape. There is growing concern that certain variants may be responsible for more severe disease as well there is concern for potential vaccine escape, thus increasing the chance for post-vaccination infection.

As capacity for whole genome sequencing (WGS) increases, CDPH is putting out a call to all healthcare providers in the state to submit respiratory specimens for WGS and serum specimens to measure antibody response from hospitalized COVD-19 patients. Please review the attached guidance for additional information.

Please contact your local public health laboratory for submittal instructions[1]. For additional questions or questions pertaining to submission of serum specimens, please contact CDPH VRDL at or 510-310-8585.



Original signed by Cassie Dunham

Cassie Dunham

Acting Deputy Director


[1] For local health jurisdictions recommending specimen submission directly to VRDL, providers should review the VRDL specimen shipping guidelines webpage and complete a General Purpose Specimen Submittal Form (PDF)


Page Last Updated :