Evaluate the method for influenza A/H3N2 virus isolation on MDCK cell culture

Abstract

Virus isolation rates for influenza A/H3N2 virus from human surveillance samples are lower than molecular detection rates for the specific viral genomes. The current study was conducted to provide technical data for isolation method of influenza A/H3N2 virus on MDCK cell performing in National/WHO Influenza Centre at Pasteur Institute in Ho Chi Minh city. The virus isolation method using virus isolation substrates Madin–Darby canine kidney (MDCK) cell cultures. Realtime RT-PCR was used as gold standard for 35 positives and 65 negatives with human influenza A/H3N2 virus. Hemagglutination (HA) and hemagglutination inhibition (HAI) assay were used to detect the present of influenze A/H3N2 virus base on the characteristics of the virus’s surface hemagglutinin molecules. The research gave data for four main criterions to evaluate the influenza A/H3N2 virus isolation on MDCK cell culture: Limit of detection (LOD), precision, sensitivity and specificity. The isolated sample 16 HA units was used for determining limit of detection, the result was about 1/100,000. The study witnessed a slight fluctuation of precision. The outcome gave high weight for the specificity of this technique 100%. Meanwhile, the sensitivity was 31%. Key word: Influenza MDCK cell Realtime RT-PCR Hemagglutination Hemagglutination inhibition.