BACKGROUND
Rapid influenza diagnostic tests (RIDTs) have long been used in clinical settings to identify patients infected with influenza. Studies have shown that point-of-care RIDTs reduce the use of antibiotics and improve clinical outcomes, but in many cases test performance is unreliable.1 Although specificity is consistently over 90%, some studies report sensitivity rates as low as 17.8%.2 New advances in technology have improved overall sensitivity, but performance is still inconsistent and false negatives are fairly common. 3-6
The COVID-19 pandemic resulted in federal policy that allowed rapid antigen testing in homes, schools, and other community settings for the first time. This policy shift occurred, however, without formal evaluations of performance characteristics of specific over-the-counter tests in community settings. Many academic institutions conducted routine SARS-CoV-2 rapid antigen testing and experienced high specificity and varying sensitivity, similar to observations in clinical settings when testing for influenza.2
In the aftermath of the pandemic, we are likely to see the emergence of additional rapid testing technologies intended for school or community use. In addition to bolstering existing disease surveillance systems that are often reliant on clinical data, the near real-time results in densely populated settings like kindergarten-12th grade (K-12) schools may help to contain outbreaks of influenza and other respiratory viruses. Accordingly, it is necessary to evaluate performance characteristics of rapid tests in community settings. Such information can be essential to educating the public on how best to interpret results. Thus, we conducted a detailed analysis of performance characteristics of Sofia Influenza A+B Fluorescent Immunoassay (FIA) to identify factors that could influence the sensitivity and specificity of RIDTs for K-12 students in a community setting.
METHODS