Advancing point of care testing for respiratory viruses: A post pandemic perspective

As seen during the COVID-19 pandemic, respiratory viruses are often challenging to diagnose and highly contagious, posing a significant threat to public health. Respiratory viruses can lead to severe illness, such as pneumonia or bronchitis, especially in vulnerable populations.

Timely and accurate diagnosis is critical to managing and controlling outbreaks, reducing transmission, and providing appropriate patient care. Point of care (POC) testing has emerged as a transformative tool in this context, offering rapid and reliable diagnostic capabilities at or near the site of patient care.¹

So, where are we now post-pandemic? Dr. Allison McGeer, a renowned expert in infectious diseases, has been at the forefront of advancing POC testing for respiratory viruses. In a recent webinar, Dr. McGeer shared her insights on the current state and future potential of POC testing technologies. She emphasized the importance of these innovations in improving clinical care and public health responses.

“If you had told me a decade ago that everybody I know with diabetes was going to have a monitor that they could watch on their phone and see their blood sugars 24-7, I probably would not have believed you.” ~ Dr. McGeer 

POC technology is rapidly evolving. It covers a range of testing, from diagnostic tests performed in hospitals at the time of care, to independently managed lab tests conducted outside hospitals, and self-testing at home.

When looking at the evolution of respiratory testing from lab-based setups to POC testing technologies, Dr. McGeer emphasizes the need to balance accuracy and practicality, especially when tests are administered outside traditional laboratory settings

As respiratory virus outbreaks continue to challenge healthcare systems globally, advancements in POC testing represent a critical step forward in enhancing the ability to detect, diagnose, and manage respiratory infections effectively. Furthermore, these advancements have made testing more accessible to the general public, facilitating quicker diagnoses and timely treatment.

It is important to continue to adapt and improve testing while understanding the unique challenges that come with implementation. For lab leaders, managing the process effectively can improve outcomes for both individual patients and larger populations.

POC testing is often scrutinized more heavily than traditional lab tests. “In laboratories, we like to think we never make mistakes, but errors do happen. It’s important to recognize that POC testing isn’t perfect, but neither are traditional labs. The key is finding a balance and understanding the limitations of each.”

The U.S. Food and Drug Administration (FDA) helps guide the use of POC testing, categorizing tests based on their complexity. Clinical Laboratory Improvement Amendments (CLIA)-waived tests, for example, are designed to be so simple and accurate that they minimize the risk of erroneous results, even when performed outside of a lab setting. This is critical in environments where rapid testing can prevent undertreatment or overtreatment of patients, a significant concern in both healthcare costs and patient safety.

At-home testing represents the furthest end of the POC testing spectrum, allowing patients to manage their own diagnostics. These tests need to be exceptionally simple and reliable, with minimal room for error. However, even at-home tests are not foolproof, and ensuring their accuracy remains a challenge. We look to regulatory frameworks to ensure the reliability and accuracy of tests, which is crucial for guiding clinical decisions and public health responses.

With the rise of POC tests, Dr. McGeer outlined several critical factors when selecting and implementing POC testing devices:

1. Performance Characteristics: The accuracy and reliability of the test are paramount. Evaluating these characteristics ensures that the test will deliver consistent and correct results.

2. Cost: Costs include not only the price of the device and its accessories but also the expenses related to human resources needed to operate it. Budget considerations must encompass all these aspects to ensure sustainability.

3. Storage Requirements: Tests often have specific storage needs regarding temperature and shelf life. Effective management of these requirements is essential to maintain test efficacy and avoid waste.

4. Footprint: The physical size and space requirements of the machine must be suitable for its intended location, whether in a hospital, remote clinic, or other settings.

5. Durability: Machines must be robust enough to withstand transportation, extreme temperatures, and occasional physical impact. Durability is crucial for ensuring the device functions reliably in various environments.

6. Testing Time and Capacity: The time required to complete a test and the number of tests that can be run simultaneously are important factors. Machines that offer faster processing and the ability to handle multiple tests concurrently are preferable In high-traffic areas.

7. Training and Usability: The complexity of the test and the level of training required for operators needs to be considered. Ensuring that staff are adequately trained and that the test is user-friendly can minimize errors and improve results.

8. Internal Controls and Quality Assurance: Establishing robust internal controls and quality assurance measures helps maintain the accuracy and reliability of the test results, especially when performed by a diverse group of operators.

9. Reporting and Communication: Effective communication of test results to healthcare providers and integration with electronic patient records or public health systems is crucial. Advances in technology, such as real-time data sharing seen with modern glucose monitors, set a high standard for future POCT systems.

There will always be a need for continued advancements in POCT communication, suggesting that future developments should include better integration with electronic health records and public health reporting systems;

Challenges and clinical benefits of respiratory virus point of care testing for influenza:

One of the major challenges with POC testing for respiratory viruses, particularly influenza, is the low positivity rate. During peak flu seasons, only about 20-30% of adults with acute respiratory infections test positive for influenza. This low detection rate makes single-virus tests less useful and often unsatisfactory for patients, as many symptomatic individuals do not receive a definitive diagnosis.

Clinically, POC testing provides better outcomes by enabling earlier antiviral treatment for influenza-positive patients, reducing unnecessary antiviral use for those who are not infected, and potentially decreasing unnecessary or inappropriate antibiotic prescriptions.

Challenges and clinical benefits of respiratory virus point of care testing for SARS-CoV-2:

The COVID-19 pandemic highlighted the importance of POC testing in managing respiratory viral infections. Rapid testing for SARS-CoV-2 allowed for timely treatments such as steroids and anticoagulants, improving patient management. However, challenges remain, such as determining the precise benefits of early antiviral treatments for both influenza and COVID-19, especially in high-risk and hospitalized patients. The pandemic also demonstrated that while rapid adaptation is possible in crisis situations, maintaining this efficiency in routine, seasonal settings is more difficult.

In preparing for the next pandemic, particularly within long-term care facilities, rapid POC testing can significantly impact disease transmission and patient outcomes. However, barriers such as the lack of evidence for cost-effectiveness and resistance to shifting testing responsibilities from laboratories to other settings hinder the widespread adoption of POC testing. To effectively integrate POC testing into public health surveillance systems, substantial changes and coordination are required between public health authorities and laboratory services.

Overall, the technology for POC testing is advancing rapidly, offering significant potential benefits for both individual patient care and population health management. Successful implementation requires careful consideration of test performance, clinical outcomes, workflow integration, and collaboration among various healthcare stakeholders. The COVID-19 pandemic has shown that rapid and effective adaptation is possible, but achieving this in routine settings remains challenging. Continued efforts to refine POC testing and address implementation barriers will enhance preparedness for future pandemics and improve overall healthcare delivery for respiratory viral infections.

To hear more from Dr. McGeer, check out the full webinar, Point of Care testing for respiratory viruses: a post-pandemic perspective.