Cepheid's Multi-Target Test Design Enables Detection of Influenza Variants

By LabMedica International staff writers
Posted on 09 Dec 2022

Image: Xpert Xpress CoV-2/Flu/RSV plus enables actionable, rapid respiratory results (Photo courtesy of Cepheid)

Variants of the (H1N1)pdm09 and A(H3N2) viruses containing matrix gene mutations are currently circulating around the world. The two recently identified mutations in the matrix genes of the Human Influenza A virus have been reported to cause matrix gene target failure (MGTF) for several commercial diagnostic tests. Recombination and other mutations of the viruses impact the performance of molecular diagnostic tests – which may lead to an increase in false negative test results. The greatest impact occurs in tests that detect only one genetic target of the influenza genome. The currently circulating mutant strains of influenza highlight the need for multi-target diagnostic tests.

Cepheid’s (Sunnyvale, CA, USA) respiratory test design enables detection of these new variants, and with similar symptoms across various illnesses such as the flu, respiratory syncytial virus (RSV) disease, and COVID-19, when accurate and fast diagnosis is critical to patient care. Cepheid's respiratory tests, the Xpert Xpress Flu/RSV, Xpert Xpress SARS-CoV-2/Flu/RSV and Xpert Xpress CoV-2/Flu/RSV plus, all utilize a multi-target approach for the detection of influenza, providing target redundancy to mitigate the potential impact of genetic shift and drift on strain detection.

"In developing our portfolio of respiratory tests, we include multiple conserved gene targets to account for genetic drift within the influenza genome," said David Persing, M.D., Ph.D., EVP and Chief Scientific Officer of Cepheid. "The resulting target redundancy mitigates the impact of mutational drift. Our three-gene target design for detection of influenza A reduces the risk of false-negative test results, even in the event of an MGTF."

"The Medicines and Healthcare Products Regulatory Agency (MHRA), United Kingdom (UK) has asked all influenza test manufacturers in the UK to analyze their tests for any impact to diagnostic performance against the H1N1pdm09 strain. Our Scientific Affairs team performed in silico testing of the performance of our portfolio of influenza tests against the new H1N1pdm09 strain," said Mike Loeffelholz, Ph.D., D(ABMM) and Senior Director, Scientific Affairs. "Our analysis shows 100% predicted coverage for this strain."

Related Links:
Cepheid