March 21 LOCS (CDC) Email

Audience: Clinical Laboratory Professionals
Subject: Discontinue Use of the A549/MV1LU Mix for Respiratory Viral Culture Panels and Review Updated Biosafety FAQs
Level: Laboratory Alert

Because of the risk of infection with SARS-CoV-2 among laboratory workers, CDC recommends that laboratories discontinue the use of the A549/MV1LU mix when they perform respiratory viral culture panels. Using these specific cell lines has been shown to result in a very low level of SARS-CoV replication. CDC recommends that laboratories perform respiratory viral culture panels using cell lines that will not support SARS-CoV viral replication.

Additionally, CDC has recently updated the biosafety guidelines and frequently asked questions (FAQs). According to the updated guidelines, cultures or isolates of SARS-CoV-2 may now be shipped according to regulations for UN 3373 Biological Substances, Category B.

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