Sensitivity and specificity of a rapid influenza diagnostic test in children and clinical utility during influenza A (H1N1) 2009 outbreak

Introduction The influenza A (H1N1) 2009 outbreak caused death and a disruption of public health services. Rapid influenza diagnostic tests (RIDT) could be helpful to ease the triage of patients and prevent an overload of emergency and laboratory facilities. Objectives To compare the sensitivity and specificity of the Clearview Exact Influenza A&B test and real-time reverse transcription(RT)–PCR to detect influenza A (H1N1) 2009 in a paediatric emergency department of a paediatric teaching hospital in Paris, France. Methods 76 children with an influenza-like illness and either severe symptoms or an underlying medical condition were prospectively recruited between July 2009 and October 2009. RIDT and RT–PCR were simultaneously performed and compared. Results Among 39 influenza A (H1N1) 2009 RT–PCR-positive children (median age 5 years), 23 Clearview Exact Influenza A&B tests were positive. Sensitivity was 59% (95% CI 42.2 to 74) and specificity was 94.6% (95% CI 80.5 to 99.1). Conclusions This study shows a sensitivity of RIDT of 59%, in agreement with other prospective studies, which could be useful in clinical practice for diagnosis influenza A (H1N1) 2009 in children. In outbreaks of a high prevalence, such as the 2009 outbreak, this test can help to prevent an overload of public health services.