[Evaluation of an immunochromatography test using enzyme immunoassay for rapid detection of influenza A and B viruses].
We evaluated the performance of an improved version of Espline Influenza A & B-N (Fujirebio Inc., Japan), an immunochromatography test using enzyme immunoassay for rapid diagnosis of influenza A and B. The test produced positive results for four strains of influenza viruses and thirty-one influenza viral antigens and negative results for all of thirty strains of other respiratory viruses that were tested. The detection limit of this test was 5.8 x 10(2) to 5.8 x 10(3) pfu/assay, which is more sensitive than the old version of Espline. Furthermore, 715 respiratory specimens collected from the patients (children, 79.4%; adults, 18.5%; unknown, 2.1%) with influenza-like illnesses during the 2002/2003 influenza season in Japan were tested as part of a clinical evaluation of this test. The relative performance of this test compared to cell culture and nested RT-PCR results were examined. In the cell cultures, influenza viruses were detected in 488 of the 715 specimens (overall, 68.3%; AH3, 41.7%; B, 26.4%; AH3 and B, 0.1%). For influenza A, the sensitivity of this test was 95.4% (125/131) for nasal aspirates, 96.8% (92/95) for nasal swabs, and 85.1% (63/74) for throat swabs. For influenza B, the sensitivity of this test was 91.2% (52/57) for nasal aspirates, 88.1% (59/67) for nasal swabs, and 71.6% (48/67) for throat swabs. The new test exhibited a remarkably higher sensitivity to influenza A in throat swabs than the old version of Espline. Only two false positive results were obtained out of a total of 223 virus negative specimens; the specificity of the test was 100% (88/88) for nasal aspirates, 97.6% (81/83) for nasal swabs, and 100% (52/52) for throat swabs. We conclude that the new Espline Influenza A&B-N rapid diagnostic test is easy to use and has a high sensitivity and specificity, especially for influenza A.
Mitamura
Keiko
K
Department of Pediatrics, Kawasaki Municipal Hospital.
Yamazaki
Masahiko
M
Ichikawa
Masataka
M
Kimura
Kazuhiro
K
Kawakami
Chiharu
C
Shimizu
Hideaki
H
Watanabe
Sumi
S
Imai
Mitsunobu
M
Shinjo
Masayoshi
M
Takeuchi
Yoshinao
Y
Sugaya
Norio
N
D000328:Adult; D002648:Child; D002845:Chromatography; D005069:Evaluation Studies as Topic; D006801:Humans; D007124:Immunoenzyme Techniques; D009980:Influenza A virus / Q000302:isolation & purification*; D009981:Influenza B virus / Q000302:isolation & purification*; D007251:Influenza, Human / Q000175:diagnosis*; D011933:Reagent Kits, Diagnostic / Q000592:standards*; D012680:Sensitivity and Specificity
D011933:Reagent Kits, Diagnostic