Evaluation of indirect fluorescent antibody assays compared to rapid influenza diagnostic tests for the detection of pandemic influenza A (H1N1) pdm09

• Published in: PloS one 2012-03, Vol.7 (3), p.e33097-e33097
• Main Authors: Nutter, Sandra, Cheung, Michele, Adler-Shohet, Felice C, Krusel, Kathryn, Vogel, Kate, Meyers, Hildy
• Format: Article
• Language: English
• Subjects: Adult; Age factors; Antibodies; Antigens; Biology; California - epidemiology; Child; Child, Preschool; Children; Comparative analysis; Cross infection; Diagnostic systems; Diagnostic tests; Disease control; Epidemics; Epidemiology; False Negative Reactions; False Positive Reactions; Fluorescence; Fluorescent Antibody Technique - methods; Fluorescent Antibody Technique - standards; Health surveillance; Hospitalization; Hospitals; Humans; Identification; Illnesses; Influenza; Influenza A; Influenza A Virus, H1N1 Subtype - genetics; Influenza, Human - diagnosis; Influenza, Human - epidemiology; Influenza, Human - virology; Inpatients - statistics & numerical data; Medical diagnosis; Medical laboratories; Medical tests; Medicine; Middle Aged; Molecular Diagnostic Techniques - methods; Molecular Diagnostic Techniques - standards; Nosocomial infections; Outpatients - statistics & numerical data; Pandemics; Patients; Pneumonia; Polymerase chain reaction; Polymerase Chain Reaction - methods; Polymerase Chain Reaction - standards; Public health; Reproducibility of Results; Respiratory diseases; Sensitivity; Sensitivity and Specificity; Sepsis; Studies; Swine flu; Swine influenza; Viruses
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0033097

Performance of indirect fluorescent antibody (IFA) assays and rapid influenza diagnostic tests (RIDT) during the 2009 H1N1 pandemic was evaluated, along with the relative effects of age and illness severity on test accuracy. Clinicians and laboratories submitted specimens on patients with respiratory illness to public health from April to mid October 2009 for polymerase chain reaction (PCR) testing as part of pandemic H1N1 surveillance efforts in Orange County, CA; IFA and RIDT were performed in clinical settings. Sensitivity and specificity for detection of the 2009 pandemic H1N1 strain, now officially named influenza A(H1N1)pdm09, were calculated for 638 specimens. Overall, approximately 30% of IFA tests and RIDTs tested by PCR were falsely negative (sensitivity 71% and 69%, respectively). Sensitivity of RIDT ranged from 45% to 84% depending on severity and age of patients. In hospitalized children, sensitivity of IFA (75%) was similar to RIDT (84%). Specificity of tests performed on hospitalized children was 94% for IFA and 80% for RIDT. Overall sensitivity of RIDT in this study was comparable to previously published studies on pandemic H1N1 influenza and sensitivity of IFA was similar to what has been reported in children for seasonal influenza. Both diagnostic tests produced a high number of false negatives and should not be used to rule out influenza infection.