Influenza virus detection in clinical specimens
Havlícková, M.; Pljusnin, A.Z.; Tůmová, B.
Acta Virologica 34(5): 449-456
1990
ISSN/ISBN: 0001-723X PMID: 1981455 Document Number: 363831
The authors compared the resutls of influenza A (H1N1) and influenza A (H3N2) virus detection in nasopharyngeal swabs from flu patients by molecular hybridization (MH), ELISA, virus isolation and seroconversion. Using the immunofluorescence (IF) technique influenza virus was detected in cells suspensions from the first chick embryo passage. Altogether 63 swabs from various epidemic seasons were separated into 3 groups according to specimen sampling and storage. It was shown that influenza virus RNA could be found in 16 out of 22 swab specimens (72%) stored at -70.degree. C without thawing and that ELISA revealed the influenza virus antigen in 19 cases (86%); in contrast, IF was positive in 6 (27%) and virus isolation in 5 (22%) cases only. However, the positive rate of MH decreased to 9% in 21 swab specimens repeatedly thawed and stored at -20.degree. C and was completely negative after prolonged storage of repeatedly thawed samples. Despite these conditions, ELISA was still successful in both latter sample groups (71-80%). For specificity control, 29 samples coming from patients with influenza B virus and other respiratory virus diseases (adeno- and respiratory syncytial virus) were used.