Application of Directigen FLU-A for the detection of influenza A virus in human and nonhuman specimens.
AUTOR(ES)
Ryan-Poirier, K A
RESUMO
Directigen FLU-A, a new enzyme immunoassay membrane test, rapidly detects influenza A virus antigen in specimens from patients. Nasopharyngeal washes and pharyngeal gargles were used to determine the effectiveness of the assay as applied to different types of routinely collected clinical samples. All specimens had been previously shown to contain influenza A virus by virus isolation in tissue culture. Directigen FLU-A was 90% sensitive (95% confidence interval, 56 to 99.7%) with nasopharyngeal washes but only 39% sensitive (95% confidence interval, 17 to 64%) with pharyngeal gargles (P = 0.018) when used with samples containing similar amounts of infectious virus (50% tissue culture infective dose, 1.0 to 4.5). The intensity of the positive reaction with Directigen FLU-A did not correlate with the amount of virus in the specimens. Directigen FLU-A was found to detect cell-associated antigen more readily than free virus; only 20 infected cells were required to identify cell-associated influenza A virus antigen, whereas the limit of detection for free virus was 1.63 x 10(3) infectious virus particles. These findings suggest that Directigen FLU-A detects the cell-associated antigen present in clinical specimens rather than free virus. In addition, Directigen FLU-A detected avian and swine influenza A viruses in both cloacal swabs (75% sensitivity) and swine lung homogenates (86% sensitivity), indicating its potential usefulness in the surveillance of nonhuman influenza A viruses.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=265226Documentos Relacionados
- Comparison of Directigen FLU-A with viral isolation and direct immunofluorescence for the rapid detection and identification of influenza A virus.
- Comparison of rapid immunofluorescence procedure with TestPack RSV and Directigen FLU-A for diagnosis of respiratory syncytial virus and influenza A virus.
- Comparison of the Directigen Flu A+B Membrane Enzyme Immunoassay with Viral Culture for Rapid Detection of Influenza A and B Viruses in Respiratory Specimens
- Evaluation of the Directigen FluA+B Test for Rapid Diagnosis of Influenza Virus Type A and B Infections
- Enzyme immunoassay for direct detection of influenza type A and adenovirus antigens in clinical specimens.