[Comparison of three rapid diagnostic kits using immunochromatography for detection of influenza A virsuses]

In 2004, 3 new rapid influenza diagnostic kits using immunochromatography that allow type differentiation became commercially available. They are the ESPLINE Influenza A & B-N (Fujirebio Corp., Japan: ESPLINE-N hereafter), QuickVue Rapid SP influ (Quidel Corp., USA: QuickVue), and POCTEM INFLUENZA A/B (INTERNATIONAL REAGENTS Corp., Japan: POCTEM). The authors performed a prospective study that compared the usefulness among the 3 kits in 151 children with suspected influenza, who were examined within 3 days after onset, between January and March, 2004. Nasopharyngeal aspirates were collected, and viruses were isolated. The residual samples were diluted and centrifuged, and the supernatant was used for the rapid diagnosis tests. Influenza virus AH3 was isolated in 95 children and influenza B virus in 3. In the 95 children with influenza virus AH3, the sensitivity and specificity of ESPLINE-N were 100% and 100%, respectively, those of QuickVue were 99% and 91%, and those of POCTEM were 91% and 100%. The sensitivity of POCTEM was significantly lower than that of the other 2 kits (p < 0.01), and the specificity of QuickVue was significantly lower than that of the other 2 kits (p < 0.05). Examination was performed within 1 day after onset in 55 of the 95 children, including 30 who underwent examination within 6 hours after the development of fever. The body temperature was less than 38.0 degrees C in 14 of the 95 children. In all children including these children, virus detection was possible by ESPLINE-N. ESPLINE-N allowed very accurate diagnosis of influenza A using samples prepared by diluting and centrifuging nasopharyngeal aspirates.