- Analytical sensitivity varied across 11 rapid influenza diagnostic test kits as well as with different influenza viruses.
- Most RIDTs detected viral antigens in samples with the highest influenza virus concentrations, but test performance for all RIDTs dropped significantly with decreasing virus concentration.
- For highest virus concentrations, it is important to collect respiratory specimens within 24–72 hours of symptom onset.
- Clinicians should follow best practices for specimen collection and timing to improve the clinical utility of RIDTs.
- The evaluation does not represent RIDT performance in clinical settings.
- RIDTs should be used cautiously for diagnostic, treatment, and infection control decisions in clinical settings.