The first external quality #assessment of #isolation and #identification of #influenza viruses in #cell culture in the #Asia #Pacific region, 2016 (J Clin Virol., abstract)

[Source: Journal of Clinical Virology, full page: (LINK). Abstract, edited.]

The first external quality assessment of isolation and identification of influenza viruses in cell culture in the Asia Pacific region, 2016

Patrick C. Reading, Vivian K. Leung, Iwona Buettner, Leah Gillespie, Yi-Mo Deng, Robert Shaw, Natalie Spirason, Angela Todd, Kanta Subbarao, Aparna Singh Shah, Frank Konings, Ian G. Barr


Article Info: Publication History: Published online: November 01, 2017 – Accepted: October 31, 2017 – Received in revised form: October 27, 2017 – Received: August 1, 2017



  • An external quality assessment (EQA) was developed for influenza virus isolation.
  • National Influenza Centres (NICs) in the Asia Pacific Region performed the EQA.
  • NICs used a variety of techniques to confirm and identify influenza virus isolates.
  • The EQA revealed good proficiency and highlighted the need to improve sensitivity.




The isolation and propagation of influenza viruses from clinical specimens are essential tools for comprehensive virologic surveillance. Influenza viruses must be amplified in cell culture for detailed antigenic analysis and for phenotypic assays assessing susceptibility to antiviral drugs or for other assays.


To conduct an external quality assessment (EQA) of proficiency for isolation and identification of influenza viruses using cell culture techniques among National Influenza Centres (NICs) in the World Health Organisation (WHO) South East Asia and Western Pacific Regions.

Study design

Twenty-one NICs performed routine influenza virus isolation and identification techniques on a proficiency testing panel comprising 16 samples, containing influenza A or B viruses and negative control samples. One sample was used exclusively to determine their capacity to measure hemagglutination titer and the other 15 samples were used for virus isolation and identification.


All NICs performed influenza virus isolation using Madin Darby canine kidney (MDCK) or MDCK-SIAT-1 cells. If virus growth was detected, the type, subtype and/or lineage of virus present in isolates was determined using immunofluorescence, RT-PCR and/or hemagglutination inhibition (HI) assays. Most participating laboratories could detect influenza virus growth and could identify virus amplified from EQA samples. However, some laboratories failed to isolate and identify viruses from EQA samples that contained lower titres of virus, highlighting issues regarding the sensitivity of influenza virus isolation methods between laboratories.


This first round of EQA was successfully conducted by NICs in the Asia Pacific Region, revealing good proficiency in influenza virus isolation and identification.

Abbreviations: CC (Collaborating Centre), EQA (external quality assessment), GISRS (Global Influenza Surveillance and Response System), WPR (WHO Western Pacific Region), SEAR (WHO South East Asia Region), NIC (National Influenza Centre), MDCK (Madin Darby canine kidney), HA (hemagglutination), HI (hemagglutination inhibition), IF (immunofluorescence)

Keywords: influenza, virus isolation, external quality assessment

© 2017 Published by Elsevier B.V.

Keywords: Influenza A; Influenza B; Diagnostic Tests; Asia Region.


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Giuseppe Michieli

I am an Italian blogger, active since 2005 with main focus on emerging infectious diseases such as avian influenza, SARS, antibiotics resistance, and many other global Health issues. Other fields of interest are: climate change, global warming, geological and biological sciences. My activity consists mainly in collection and analysis of news, public services updates, confronting sources and making decision about what are the 'signals' of an impending crisis (an outbreak, for example). When a signal is detected, I follow traces during the entire course of an event. I started in 2005 my blog ''A TIME'S MEMORY'', now with more than 40,000 posts and 3 millions of web interactions. Subsequently I added an Italian Language blog, then discontinued because of very low traffic and interest. I contributed for seven years to a public forum ( in the midst of the Ebola epidemic in West Africa in 2014, I left the site to continue alone my data tracking job.