If there’s a common thread tying all the needs in respiratory testing, it would be flexibility. Consider something as seemingly straightforward as influenza: despite being a single family of related viruses, its diagnosis is far from clear-cut. Flu testing is highly complex, with the appropriate test selected on the basis of variables like seasonality, regional epidemiology, patient age and comorbidities, occupational risk, and more.
That’s why flexibility is so important – not just for influenza but for all respiratory infection testing. Clinical lab teams should have multiple options in the type of test they choose for each case, from targeted single tests to mini multiplex panels to large syndromic panels.
With additional challenges as more healthcare systems consolidate and hospitals face increasing headwinds, flexible testing is becoming more important. When a rural hospital shuts down, for instance, local pharmacies, physician practices, and urgent-care clinics could be ideal locations for high-quality molecular testing in the community.
Any exploration of respiratory testing must also account for the needs of diagnostic stewardship. This guiding principle – of using the right test for the right patient at the right time – is best served by ensuring that clinical labs have access to all the testing options they need. And then having appropriate guidelines and algorithms for when and how to deploy each test.
Factors to consider
Respiratory infections can be challenging to diagnose – in part because they share many overlapping symptoms: fever, sore throat, and/or shortness of breath. Since treatment plans and isolation protocols vary significantly based on the underlying pathogen, it’s essential to identify the infection accurately.
However, making that diagnosis depends on several factors. Chief among them is seasonality; pathogens such as influenza and respiratory syncytial virus (RSV) often have peak seasons that can help clinical lab teams determine the most appropriate test option. During the off-season, labs may de-prioritize testing for certain pathogens and instead look to other pathogens first.
Similarly, epidemiological patterns should be considered. Clinical lab members are well-versed in the pathogens circulating in their patients’ communities, and can use that information to tailor testing appropriately.
Patient demographics also weigh heavily; healthy adults will typically be suited for more targeted tests, while children, the elderly, and the immunocompromised might need to be tested with broader panels for the most accurate picture of their health. Even occupation is important in flu testing right now, with the risk of contracting H5N1 higher among dairy workers.
Diagnostic stewardship is a worthy goal that can, unfortunately, complicate matters for clinical lab teams. It’s not enough for laboratories to know which tests are most appropriate to implement; true diagnostic stewardship also requires that physicians understand when and how to order those tests for their patients. Many lab managers lament that physicians continue to order the broadest panels available even when they are not recommended. In some cases, labs have found ways to nudge physicians in the right direction – even changing the layout of their test menu to make the most appropriate tests more prominent than those that should be used least often.
Types of tests
For respiratory testing, molecular tests have quickly become the gold standard due to their superior sensitivity compared with rapid antigen tests. Molecular assays are now recommended for flu testing by the Infectious Diseases Society of America (IDSA), as many can deliver results in just a few hours. In fact, recent versions may produce answers in 30 minutes or less.
Within the broad category of molecular tests, there are many different options – and clinical lab teams should have access to several of these to provide the required flexibility for respiratory testing.
Targeted tests are available for single pathogens, such as SARS-CoV-2 or RSV, and for a small number of closely related pathogens, such as flu A/B. These tests might be the go-to choice for healthy adults during a large local COVID-19 outbreak or a particularly bad flu season.
Mini panels allow testing for multiple pathogens but stop well short of the large syndromic panels. During a respiratory season with several commonly circulating viruses, for example, a mini panel covering flu A/B, RSV, and SARS-CoV-2 could be an ideal option for most patients. Covering multiple targets in a single rapid molecular test allows clinical teams to obtain results in a clinically actionable time frame, avoiding the delays and increased workload that come with running single-pathogen tests sequentially. Mini panels also have an economic benefit, as payers often prefer testing for a smaller group of targets and are more amenable to reimbursing these tests.
Finally, there are large syndromic panels. These might cover dozens of targets, including those that are relatively clinically rare among the general population, but tend to be more prevalent in highly vulnerable populations, such as residents of long-term care facilities, or patients with recent travel to endemic regions.
Where to test
Respiratory infection testing is both common and complex, and flexibility in testing location can be just as critical as the choice of test itself. While decentralized testing has gained traction, the rapid antigen tests often used in urgent care clinics and physician offices frequently lack the sensitivity needed to meet diagnostic demands – leaving gaps for both providers and patients.
In this scenario, point-of-care molecular testing can offer meaningful advantages. During a severe flu season, for instance, enabling otherwise healthy individuals to access molecular tests at clinics or pharmacies could help preserve laboratory capacity for hospitalized or critically ill patients. To maximize clinical utility, point-of-care tests should align with the pathogen coverage of central laboratories. A mini panel targeting influenza A/B, RSV, and SARS-CoV-2 would be particularly useful for triaging patients. This could enable rapid, actionable insights that support test-to-treat clinical decisions and help contain community transmission.
Hospitals could also benefit from this approach during peak respiratory seasons. Many facilities set up triage stations outside emergency departments to manage patient flow. Deploying fast, reliable molecular testing platforms at these sites could prevent central labs from becoming overwhelmed. These point-of-care devices, operated by Clinical Laboratory Improvement Amendments (CLIA)-waived personnel, could be strategically placed where they’re needed most – enhancing responsiveness while maintaining diagnostic integrity and stewardship.
Moving forward
There is no one-size-fits-all solution for respiratory testing. To set themselves and their patients up for success, laboratory teams can prioritize flexibility as they select testing platforms. Devices that can run a combination of targeted tests and mini panels, or mini panels and syndromic panels, will be more useful for a greater number of cases than platforms dedicated to a single type of test.
Looking ahead, lab managers may also want to consider placing point-of-care devices outside the lab or working with local health partners to help them adopt molecular testing platforms designed for use in pharmacies, urgent care facilities, long-term care facilities, and other non-hospital settings.
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