Comparison of Rapid Influenza Diagnostic Tests With Digital Readout Systems and Conventional Rapid Influenza Diagnostic Test for Influenza Virus Detection

@#Introduction: Rapid diagnosis for influenza virus infection is essential for proper patient management, delivering prompt treatment and reducing unnecessary antiviral therapy. Early diagnosis helps in disease prevention and control. Real-time reverse transcription-polymerase chain reaction (RT-PCR) assay yields high sensitivity and specificity in detecting influenza virus infection. However, it is relatively expensive and requires trained personnel and special equipment. In this study, we compared two rapid influenza diagnostic tests (RIDTs): digital readout systems (STANDARD™ F Influenza A/B FIA, fluorescence immunoassay) and conventional visual confirmation (QuickNavi™-Flu2, chromatography immunoassay) with the real-time RT-PCR assay. Methods: Two hundred ninety-eight respiratory samples were obtained from patients suspected of influenza infection at Siriraj Hospital from December 2018 to December 2019. Results: Real-time RT-PCR results showed the detection of influenza A virus in 99 samples (60%), influenza B virus in 61 samples (37%) and co-infection by both viruses in 5 samples (3%) by the real-time RT-PCR assay. The QuickNavi™-Flu2 sensitivity for detecting influenza A and B viruses were 81.73% and 84.85%, and the specificity was 100%. The STANDARD™ F Influenza A/B FIA sensitivity for detecting influenza A and B viruses were 84.62% and 83.33%, respectively. The specificity for influenza A virus detection was 99.25% and 94.74% for influenza B virus. Conclusion: The STANDARD™ F Influenza A/B FIA and the QuickNavi™-Flu2 showed acceptable and comparable sensitivity and specificity. Both RIDTs are potential alternative methods of real-time RT-PCR for rapid screening of influenza virus infection.

Evaluation of the Performance of a New Chromatographic Assay BD Veritor System for Rapid Detection of Influenza A & B / 대한임상미생물학회지

BACKGROUND: For early diagnosis and treatment of influenza, rapid influenza diagnostic tests are commonly used. We evaluated the performance of the BD Veritor System for Rapid Detection of Flu A+B (BD Veritor System; BD Diagnostics, USA) compared to multiplex real-time RT-PCR. METHODS: A total of 3,213 nasal and nasopharyngeal swab specimens in transport media from patients with influenza-like symptoms were tested with the BD Veritor System from December 2013 to April 2014. The sensitivity and specificity of 127 specimens were determined simultaneously using multiplex real-time RT- PCR with the AdvanSure RV real-time PCR (AdvanSure PCR; LG Life Sciences, Korea). RESULTS: Influenza viruses were detected in 41.3% (1,327/3,213) of all specimens tested using the BD Veritor System. Of the 127 specimens, 27 influenza A and 17 influenza B viruses were identified by the AvanSure PCR. The sensitivity and specificity of the BD Veritor System relative to the AdvanSure PCR was 85.2% and 99.0% for influenza A, and 58.8% and 99.1% for influenza B. Of the 190 specimens that tested negative using the BD Veritor System, the AdvanSure PCR detected influenza A and influenza B in 19 and 13 specimens, respectively. The mean threshold cycle (Ct) values of the antigen positive specimens were lower than those of the antigen negative specimens. CONCLUSION: The BD Veritor System showed excellent specificity for both influenza types and good sensitivity for influenza A. However, the system was less sensitive for influenza B compared to multiplex real-time RT-PCR. For accurate diagnosis of false negative specimens, a molecular diagnostic test should be performed. The BD Veritor system could be a useful tool for screening and early diagnosis of influenza.

<b>Development of A Decision Making Model for the Management of Influenza. A Proposal of Diagnostic Policy </b><b>Based on Phenomena and Therapeutics. </b> / 日本東洋医学雑誌

The management of influenza has dramatically changed since the introduction of the rapid influenza diagnostic test, or RIDT, and neuraminidase inhibitors (NI). However, it is still far from optimal due to low RIDT sensitivity and problems involving NI such as side effects and the potential emergence of resistant virus.Therefore, we developed a decision-making model for the management of influenza, which includes Kampo medicines in its strategies. First, the severity of patients is evaluated. If a patient is judged at severe or high-risk, intravenous NI would be the main component of treatment. If a patient has neither a severe condition nor is at high-risk, the patient would be asked to choose either NI or Kampo medicine. In the former, RIDT would be used if pretest probability was less than 50%, but it would not be used if it was more than 50%, based on the lack of influence on the post-test probability. For the latter, RIDT would be not used in general as Kampo targets “phenomena”, not the virus <i>per se</i>. This model enables us to optimize the use of RIDT by appropriately selecting patients based on the characteristics of RIDT, and by avoiding unnecessary tests and their misinterpretation.