Rapid influenza diagnostic test explained

A rapid influenza diagnostic test (RIDT) tells whether a person has a current influenza infection by detecting the influenza viral nucleoprotein antigen. Commercially available RIDTs can provide results within 30 minutes. These results can be observed by a color change or other visual signals.^{[1] [2]} For clinicians, RIDTs serve as a first-line test that can be confirmed (especially if negative) by traditional diagnostic tests. RIDTs also allow clinicians to promptly start antiviral treatment in high-risk populations, to formulate effective infection control measures, and to make informed decisions regarding diagnostic investigations.^{[3] [4]} RIDTs have been shown to reduce chest radiography and blood tests in ambulatory care settings, but not antibiotic prescribing, or time in the emergency department.^[5]

Accordung to a study, an H1N1 rapid test had a sensitivity of 66 %, corresponding to a false-negative probability of 34 % in detecting H1N1.^[6]

Sample collection

RIDT accuracy may be dependent on collection technique used to obtain the sample. Samples used for RIDT include respiratory specimens such as throat, nose, and nasopharyngeal secretions, as well as aspirate or washings collected from the trachea.^[7]

See also

• Viral culture

Further reading

• Web site: Interim Guidance for the Detection of Novel Influenza A Virus Using Rapid Influenza Diagnostic Tests. 2009-08-10. H1N1 Flu. Centers for Disease Control and Prevention. 2009-11-23.

Notes and References

1. Vemula SV, Zhao J, Liu J, Wang X, Biswas S, Hewlett I . Current Approaches for Diagnosis of Influenza Virus Infections in Humans . Viruses . 8 . 4 . 96 . April 2016 . 27077877 . 4848591 . 10.3390/v8040096 . free .
2. Web site: Rapid Influenza Diagnostic Tests Seasonal Influenza (Flu) CDC. 2017-04-07. www.cdc.gov. 2018-09-08.
3. Web site: Accuracy of Rapid Influenza Diagnostic Tests: A Meta Analysis. 2012-04-03. www.annals.org. 2018-11-01.
4. Chartrand C, Pai M . How accurate are rapid influenza diagnostic tests? . Expert Review of Anti-Infective Therapy . 10 . 6 . 615–7 . June 2012 . 22734950 . 10.1586/eri.12.49 . free .
5. Lee. Joseph J. Verbakel. Jan Y. Goyder. Clare R. Ananthakumar. Thanusha. Tan. Pui San. Turner. Phillip J. Hayward. Gail. Van den Bruel. Ann. 4 October 2018. The clinical utility of point-of-care tests for influenza in ambulatory care: A systematic review and meta-analysis. Clinical Infectious Diseases. 69. 1. 24–33. 10.1093/cid/ciy837. 30285232. 6579962.
6. Louie JK, Guevara H, Boston E, Dahlke M, Nevarez M, Kong T, Schechter R, Glaser CA, Schnurr DP . Rapid influenza antigen test for diagnosis of pandemic (H1N1) 2009 . Emerging Infectious Diseases . 16 . 5 . 824–6 . May 2010 . 20409373 . 2954007 . 10.3201/eid1605.091797 .
7. Web site: Use of Influenza Rapid Diagnostic Tests . World Health Organization. Special Programme for Research and Training in Tropical Diseases . 2010 .