Behavioral Patterns and Patient Self-completed Diagnostic Testing Study of Respiratory Viral Infection "Home Testing of Respiratory Illness"

Background and Rationale

Acute respiratory infections (ARI) cause considerable disease burden globally and can affect both the upper and lower respiratory tract. A majority of ARI are caused by viruses, like the influenza virus, while bacteria are only implicated in approximately 10% of cases . The symptomology across various viral ARI are broadly similar, but two viruses, namely influenza and respiratory syncytial virus (RSV) are associated with considerable morbidity and mortality among adults and children. More immediate virus identification would improve patient health management by triaging appropriate and timely treatment and infection-control measures to mitigate health costs, additional health complications, and total days of symptom expression.

Despite viral infections causing the majority of ARIs, 61% of those with acute respiratory symptoms receive an antibiotic treatment. Due to the rise of antibiotic resistance, the inappropriate and over-prescription of antibiotics has become a severe health risk and is contributing to greater health complications and increased mortality rates. As a result, the correct diagnosis of the various infections associated with ARIs has become even more imperative to not cause undue harm. The abundance, accessibility, and rapidly advancing technology in wearable devices contributes to the progress some studies have demonstrated in using the devices as a potential mechanism to more rapidly identify various diseases. Though limited research has explored this new perspective specifically in illnesses associated with ARI, recent findings were able to demonstrate influenza signals at a population level using step, sleep, and heart rate data collected from consumer wearable devices.

Influenza virus is important to diagnose correctly because, despite annual vaccinations, it has been associated with higher morbidity and mortality than most other ARI viruses and has been associated with greater individual symptom severity. During the 2017-2018 flu season in the United States, it was estimated that 48.8 million people became sick with influenza, 959,000 were hospitalized, and there were 79,400 deaths recorded due to influenza. Additionally, more vulnerable populations, like young children, those experiencing chronic illness, and older adults, disproportionately represent the hospitalization and death totals reported. Older adults represented 70% of influenza related hospitalizations in the 2017-2018 flu season and 90% of influenza related deaths.

The rapid diagnosis of influenza is also of particular importance due to the effectiveness of influenza antiviral medication that is largely limited to initiation within 48 hours of symptom onset. Additionally, rapid diagnosis also has the potential to enact infection control measures to attenuate viral spread, particularly among vulnerable populations, using behavioral interventions or other non-pharmaceutical approaches. Diagnosis of influenza infection in centralized laboratories has largely progressed from traditional viral culture to the use of reverse transcription-polymerase chain reaction (RT-PCR) methods . Alternatively, influenza infection can be detected within a medical office or pharmacy using commercially-available rapid diagnostic tests (RDTs) of varying complexity, cost and accuracy.