Detection of respiratory viruses from patients with influenza like illness in Guangzhou using centrifugation-enhanced shell vials method between January and June, 2009

Objective To evaluate the application of high-throughput shell vial assay in a clinical laboratory for detection of respiratory viruses from patients with ILI in Guangzhou between January and June, 2009. Methods Six hundred and fifty-two pharyngeal swab specimens were taken from ILI patents. Centrifugation-enhanced shell vials including 4 cell lines (MDCK, Hep-2, LLC-MK2 and MRC-5) were used for culture of respiratory viruses for 2-3 days. The cultures were identified by observation of cytopathic effect (CPE) , hemmaglution or hemmadsorption test as well as immunofluorescence staining. Results A total of 161 swab samples (24.69% ,161/652) were shown to have any one of the 5 common respiratory viruses including influenza A viruses ( 38. 51% , 62/161 ), influenza B virus ( 54. 65% , 88/161 ), parainfluenza viruses (4. 96% , 8/161 ) , adenovirus ( 1. 24% , 2/161 ), and respiratory syncytial virus (0. 62% ,1/161). The turnaround time was 2d for influenza viruses, 3d for adenovirus and parainfluenza viruses respectively. Conclusions (1) The shell vial method was effective, rapid and high throughout for the detection of respiratory viruses in clinical laboratories.(2)Influenza viruses were dominant in the swab samples from patients with ILI in Guangzhou between January and June with the highest appearance in the summer influenza B vires was the most common pathogen in patients with ILI in this study. Key words: Orthomyxoviridae; Vires cultivation; Respiratory tract infections