Multiplex PCR Assay Detects Four Respiratory Viruses with Single Swab

By LabMedica International staff writers
Posted on 03 Jul 2023

Image: The BD Respiratory Viral Panel for BD MAX provides four results from one specimen in a single run (Photo courtesy of BD)

SARS-Cov-2, influenza (flu), and the respiratory syncytial virus (RSV) are major respiratory infections with similar symptoms, complicating their differentiation without targeted diagnostic testing. Co-infection infection with SARS-Cov-2 and other respiratory viruses aren't uncommon, and they often exacerbate the disease severity and mortality risk compared to sole SARS-Cov-2 infection. Diagnostic testing remains the only definitive method for confirmation. Now, an innovative multiplex PCR assay is capable of detecting four respiratory viruses with just a single swab, assisting in identifying whether a patient has COVID-19, flu A +B, and/or RSV infection.

The BD Respiratory Viral Panel for BD MAX System from BD (Becton, Dickinson and Company, Franklin Lakes, NJ, USA) can simultaneously detect and distinguish SARS-CoV-2, influenza A, influenza B, and/or RSV from one sample in a single run. Utilizing a single nasal or nasopharyngeal swab, the test can ascertain if a patient has COVID-19, flu, or RSV. It eliminates the need for multiple tests or physician appointments and allows for the swift implementation of the appropriate treatment plan. Furthermore, this combined testing approach enhances testing capacity during the high-demand flu season and speeds up the diagnosis time.

In order to support an emergency use authorization (EUA) of the BD Respiratory Viral Panel for the BD Max system, BD evaluated the assay's capability to identify and differentiate between the viruses using a single nasopharyngeal or nasal swab. For this study, researchers prospectively collected swabs from individuals with respiratory symptoms across six US sites during the 2022 respiratory illness season. They also collected swabs retrospectively from two vendors between Dec. 20, 2019, and Jan. 11, 2022. They tested these samples on the BD MAX system and calculated positive and negative percent agreements (PPA and NPA) with other assays and methods. A total of 252 nasopharyngeal and 254 nasal samples were gathered and tested.

The PPA and NPA were 98.8% (95% CI, 93.6-99.8) and 98.2% (95% CI, 94.9-99.4) for SARS-CoV-2, and 100% (95% CI, 61-100) and 99.6% (95% CI, 97.7-99.9) for influenza A from nasopharyngeal samples. For prospectively gathered anterior nasal samples, these figures were similar. Although no subjects tested positive for influenza B or RSV, the NPA for both was 100% for nasopharyngeal and nasal samples.

Among the 240 retrospectively gathered nasopharyngeal samples, the PPA and NPA for influenza A, influenza B, and RSV were all high, indicating that users can expect reliable results for all three respiratory illnesses using the BD Respiratory Viral Panel. Notably, the test can yield dependable results for 24 patients every two hours and 15 minutes with less than 1.5 minutes of hands-on time per sample, thus enhancing testing efficiency.

“As seasonal outbreaks of SARS-CoV-2, flu A and B, and RSV often coincide and their symptomology are not easily differentiable without laboratory testing, the BD Respiratory Panel for BD MAX System will support accurate and concurrent diagnostic of these viruses,” said Sonia Paradis, clinical project lead at BD.

Related Links:
BD