09/01/2022: Lab Advisory: Variant Influenza Virus Infections

CDC's Laboratory Outreach Communication System (LOCS)

Audience: Laboratory Professionals

Level: Laboratory Advisory

On August 30, 2022, CDC issued a Health Alert Network (HAN) Health Advisory about recent variant influenza virus infections. In August 2022, CDC received reports of five cases of human infection with variant influenza A viruses that usually spread only in pigs. These cases were identified in West Virginia (3), Oregon (1), and Ohio (1). CDC recommends the following best practices for laboratories:

  • Clinical laboratories that collect respiratory specimens from persons suspected to have variant influenza A virus infection should refer these specimens to the appropriate state public health laboratory for subtype-specific real-time polymerase chain reaction (RT-PCR) testing.
  • Public health laboratories (PHLs) should immediately send influenza A virus specimens that cannot be subtyped or are presumptive variant influenza positive (using methods as outlined in the assay’s Instructions for Use) to CDC and submit all specimens that are otherwise unusual as soon as possible after identification. PHLs should email flusupport@cdc.gov to alert CDC that they have a specimen to submit.

Please review the HAN in detail and share this message widely with your networks.

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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)