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A patient swabs their cheek for a COVID-19 and influenza test.

Multiplex Testing: A Valuable Resource for the 2021–2022 Flu Season

With a new flu season and lessening COVID-19 restrictions, multiplex testing can improve turnaround times

Precautions put in place to stop the spread of COVID-19 including masks, social distancing, and travel reduction likely contributed to the low number of influenza cases seen throughout the United States during the 2020–2021 flu season. From September 28, 2020, to May 22, 2021, a report by the CDC found that only 0.2 percent of respiratory specimens tested by US clinical laboratories were positive for an influenza virus compared to the previous three seasons in which flu positivity rates peaked between 26.2 percent and 30.3 percent. The same report stated that during the 2020–2021 flu season, laboratory-confirmed influenza-associated hospitalizations were also the lowest recorded since the specific data collection began in 2005.

But with a new flu season upon us, the emergence of different SARS-CoV-2 variants, and lessening COVID-19 precautions due to the vaccine rollout, we cannot assume that we will maintain a low case rate during the 2021–2022 flu season. With COVID-19 and influenza strains presenting many overlapping symptoms, we must all remain vigilant and use available tools and resources, including testing options, to prevent the spread of both illnesses this season and beyond. 

The 2021–2022 flu season and multiplex testing

Multiplex testing, which allows for multiple pathogenic targets to be investigated in one test, will play a key role is this upcoming flu season. While flu season ramps up, SARS-CoV-2 variants are simultaneously emerging and spreading at a rapid pace, and we must continue clinical testing to reduce the spread of both illnesses. Specific multiplex tests can detect multiple respiratory viral pathogens at once, including SARS-CoV-2, influenza A, influenza B, and RSV, enabling providers to pinpoint the illness and provide the proper care at a faster rate than administering multiple tests and waiting for each result. 

In 2020, an estimated 50–55 percent of Americans received the flu shot, which is comparable to the current 55 percent of citizens that are fully vaccinated for COVID-19 at the time of writing. While vaccinations reduce the chances of infection, breakthrough infections can occur, making the need for multiplex testing necessary regardless of one’s vaccination status. 

Timeliness is crucial

The ability to test for multiple pathogens at once reduces the time and resources needed to determine a patient’s illness. When detecting either SARS-CoV-2 or the influenza virus, timeliness is key, as these respiratory illnesses require different  treatment plans and have differing public health implications. The sooner the cause of illness is identified, the sooner a treatment plan can be administered to the patient and proper precautions (e.g., quarantining if the patient tests positive for COVID-19) can be put in place, ultimately reducing possible infection for others.

 Increasing patient accessibility

When considering multiplex testing, patient accessibility is an important factor. A single test that can identify multiple pathogens eliminates the need for multiple diagnostics, reducing the time that individuals would need to visit a clinic or hospital to be tested.

Multiplexing is an all-in-one testing option and a powerful resource when it comes to testing for SARS-CoV-2 and influenza this flu season. While the emergence of new COVID-19 strains during flu season is concerning, multiplex testing is a resource we can use to help stop the spread of both deadly respiratory illnesses.