Best Uses of BIOFIRE SARS-CoV-2 Syndromic Testing Based on Updated WHO Guidelines

An information notice from the World Health Organization was directed towards lab professionals who use PCR testing to detect SARS-CoV-2. Read the full announcement.

• The WHO's guidance applies to nucleic acid testing technologies that use polymerase chain reaction for the detection of SARS-CoV-2—including the BIOFIRE^® Respiratory 2.1 Panel (EUA) and the BIOFIRE^® Respiratory 2.1-EZ Panel (EUA).^1,2
• The WHO's guidance states careful interpretation of weak positive results, as indicated by a high cycle threshold (Ct) value, is needed to avoid potential false positive results. This guidance is not applicable to the BIOFIRE^® FILMARRAY^® System as Ct values are not used in the qualitative detection of a target. Rather, the instrument performs a high-resolution melt analysis of the PCR products that is analyzed by the software for multiple criteria before assigning a final result. BIOFIRE System users do not need Ct values from the system to utilize the platform as intended.
• If test results do not correspond with clinical presentation, a new specimen should be taken and retested. Like most PCR testing solutions, tests that run on the BIOFIRE System are indicated as an aid for diagnosis, so healthcare providers should consider PCR results in combination with other relevant information available.
• The WHO reminds users that disease prevalence alters the predictive value of test results—as disease prevalence decreases, the risk of a false positive increases.

1. This test has not been FDA cleared or approved; this test has been authorized by FDA under an EUA for use by authorized laboratories; this test has been authorized only for the detection and differentiation of nucleic acid of SARS-CoV-2 from multiple respiratory viral and bacterial organisms; and this test is only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use of in vitro diagnostics tests for detection and/or diagnosis of COVID-19 under Section 564(b)(1) of the Act, 21 U.S.C. § 360bbb-3(b)(1), unless the authorization is terminated or revoked sooner.
2. This test has not been FDA cleared or approved; this test has been authorized by FDA under an EUA for use by authorized laboratories; this test is only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use of in vitro diagnostics for detection and/or diagnosis of COVID-19 under Section 564(b)(1) of the Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 360bbb-3(b)(1), unless the authorization is terminated or revoked sooner.