How quickly are respiratory syncytial virus (RSV) test results returned?

RSV Test Result Turnaround Times

RSV test results are available in 10-30 minutes for rapid antigen tests, approximately 1 hour for point-of-care molecular tests, and 2-13 hours for laboratory-based molecular assays, depending on the testing platform used.

Rapid Antigen Detection Tests (RADTs)

• Traditional rapid antigen tests deliver results in 10-30 minutes 1
• These tests can be performed at bedside without special laboratory equipment 2
• However, RADTs have significantly reduced sensitivity compared to molecular methods and should not be used to rule out RSV infection 1
• The clinical utility of rapid antigen tests is questionable due to high rates of false-positive and false-negative results, particularly when used outside of RSV season 1

Point-of-Care Molecular Tests

• Modern point-of-care molecular assays provide results in ≤13 minutes after test initiation 3
• The Alere i RSV assay specifically identifies most RSV-positive samples in approximately 5 minutes, with a maximum turnaround time of 13 minutes 4
• These rapid molecular tests have sensitivity and specificity comparable to laboratory-based PCR methods (>93% sensitivity and >96% specificity) 3, 4
• Point-of-care molecular platforms require minimal hands-on time and can be operated after minimal initial training 4

Laboratory-Based Molecular Testing

• Sample-to-answer molecular methods typically have turnaround times of approximately 1 hour, which may be acceptable for hospitalized patients or emergency department settings 1
• Some molecular systems like the Simplexa Flu A/B and RSV test provide results in approximately 2 hours 5
• Complex multiplex PCR assays can be divided into random-access platforms (faster, for low-to-medium volumes) and batched testing platforms (for higher volumes with longer turnaround times) 1

Clinical Context and Test Selection

The choice of testing platform should be based on clinical setting and urgency:

• Outpatient settings: Point-of-care molecular tests with <15 minute turnaround times are preferred over 1-hour laboratory-based methods 1
• Emergency departments and hospitalized patients: 1-hour sample-to-answer molecular methods are generally acceptable 1
• High-volume settings: Batched testing platforms may be more cost-effective but have longer turnaround times 1

Important Caveats

• Rapid antigen tests should not be relied upon to exclude RSV infection due to poor sensitivity 1
• Test performance varies significantly by season, with reduced accuracy outside peak RSV season 1
• False-negative molecular test results typically occur in samples with low viral load 4
• The FDA reclassified rapid antigen influenza tests in 2017 due to concerns about variable performance and poor sensitivity compared to molecular methods 1