Development and evaluation of a real-time nucleic acid sequence based amplification assay for rapid detection of influenza A.
The development and introduction of effective treatment for influenza A in the form of neuraminidase inhibitors have made the rapid diagnosis of infection important especially in high-risk populations. The aim of this study was to develop a real-time nucleic acid sequenced based amplification (NASBA) using a molecular beacon that could detect a wide range of influenza A subtypes and strains in a single reaction by targeting a conserved region of the influenza genome, and to evaluate its sensitivity and specificity against traditional laboratory techniques on a range of clinical samples usefulness during the 2003/2004 influenza season. The results demonstrated the assay to be highly sensitive and specific, detecting <0.1 TCID50 of virus stock. Three hundred eighty-nine clinical samples were tested in total from two patient groups. Overall, the real-time NASBA assay detected 64% (66/103) more influenza positive samples than cell culture and direct immunofluorescence (IF) and, therefore, was shown to be more sensitive in detecting influenza A in a wide range of respiratory samples than traditional methods. In conclusion, the real-time influenza A assay demonstrated clinical usefulness in both hospital and community populations.
Wales Specialist Virology Centre, NPHS Microbiology Cardiff, University Hospital of Wales, Cardiff, United Kingdom. Catherine.moore@nphs.wales.nhs.uk
Catherine
C
Moore
Sam
S
Hibbitts
Neil
N
Owen
Sally A
SA
Corden
Graham
G
Harrison
Julie
J
Fox
Colin
C
Gelder
Diana
D
Westmoreland
D000368:Aged; D018929:Cell Culture Techniques; D017931:DNA Primers / Q000235:genetics; D005260:Female; D006801:Humans; D009980:Influenza A virus / Q000235:genetics / Q000302:isolation & purification*; D007251:Influenza, Human / Q000175:diagnosis* / Q000401:mortality / Q000821:virology; D008297:Male; D012367:RNA, Viral / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D021161:Self-Sustained Sequence Replication / Q000379:methods*; D012680:Sensitivity and Specificity
D017931:DNA Primers; D012367:RNA, Viral