tetano
Editor, Senior Moderator
J Clin Virol. 2012 Nov 30. pii: S1386-6532(12)00404-0. doi: 10.1016/j.jcv.2012.11.005. [Epub ahead of print]
Evaluation of influenza virus antiviral susceptibility testing in Europe: Results from the first external quality assessment exercise.
Thompson CI, Lackenby A, Daniels RS, McCauley JW, Pereyaslov D, Broberg EK, Meijer A, Zambon MC.
Source
Health Protection Agency, 61 Colindale Avenue, London NW9 5EQ, UK.
Abstract
BACKGROUND:
The first antiviral susceptibility testing external quality assessment (EQA) was held for European influenza reference laboratories during winter 2010/11.
OBJECTIVES:
To assess European network influenza antiviral susceptibility testing capability and provide participants with an independent performance evaluation.
STUDY DESIGN:
The EQA panel contained ten coded specimens of inactivated human influenza A and B viruses with reduced susceptibility to neuraminidase inhibitors (NAI), or adamantanes. Twenty-four laboratories from 19 member states of the WHO European region analysed the panel using phenotypic (determination of 50% inhibitory concentration (IC(50)) values by neuraminidase (NA) enzyme inhibition assay) and/or genotypic methods.
RESULTS:
All 24 laboratories returned genotypic data for A(H1N1)pdm09 influenza virus, 18 (75%) for former seasonal A(H1N1), 16 (67%) for A(H3N2) and 15 (63%) for influenza B virus, correctly identifying NAI or adamantane reduced susceptibility-associated substitutions in the NA (mean 84%; range 52-100%) or M2 (mean 85%; range 73-94%), respectively. Thirteen laboratories (54%) returned phenotypic NAI susceptibility data. Despite inter-laboratory and inter-assay IC(50) value variation, all 13 laboratories correctly identified oseltamivir reduced susceptibility/resistance in pure preparations of A(H1N1) oseltamivir-resistant viruses. However, only 11 (85%) identified oseltamivir reduced susceptibility/resistance in a mixture of A(H1N1)pdm09 oseltamivir-sensitive/-resistant viruses. Furthermore, 3 laboratories (23%) considered oseltamivir-sensitive influenza B virus reduced susceptible/resistant.
CONCLUSIONS:
Detection of NA-H275Y in A(H1N1) viruses was achieved by most laboratories. IC(50) values and interpretation thereof varied for a sensitive/resistant virus mixture and for influenza B virus. The results of this exercise will assist harmonisation of antiviral susceptibility testing, interpretation and reporting within the European network through targeted training.
Copyright ? 2012. Published by Elsevier B.V.
PMID:
23201459
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/23201459
Evaluation of influenza virus antiviral susceptibility testing in Europe: Results from the first external quality assessment exercise.
Thompson CI, Lackenby A, Daniels RS, McCauley JW, Pereyaslov D, Broberg EK, Meijer A, Zambon MC.
Source
Health Protection Agency, 61 Colindale Avenue, London NW9 5EQ, UK.
Abstract
BACKGROUND:
The first antiviral susceptibility testing external quality assessment (EQA) was held for European influenza reference laboratories during winter 2010/11.
OBJECTIVES:
To assess European network influenza antiviral susceptibility testing capability and provide participants with an independent performance evaluation.
STUDY DESIGN:
The EQA panel contained ten coded specimens of inactivated human influenza A and B viruses with reduced susceptibility to neuraminidase inhibitors (NAI), or adamantanes. Twenty-four laboratories from 19 member states of the WHO European region analysed the panel using phenotypic (determination of 50% inhibitory concentration (IC(50)) values by neuraminidase (NA) enzyme inhibition assay) and/or genotypic methods.
RESULTS:
All 24 laboratories returned genotypic data for A(H1N1)pdm09 influenza virus, 18 (75%) for former seasonal A(H1N1), 16 (67%) for A(H3N2) and 15 (63%) for influenza B virus, correctly identifying NAI or adamantane reduced susceptibility-associated substitutions in the NA (mean 84%; range 52-100%) or M2 (mean 85%; range 73-94%), respectively. Thirteen laboratories (54%) returned phenotypic NAI susceptibility data. Despite inter-laboratory and inter-assay IC(50) value variation, all 13 laboratories correctly identified oseltamivir reduced susceptibility/resistance in pure preparations of A(H1N1) oseltamivir-resistant viruses. However, only 11 (85%) identified oseltamivir reduced susceptibility/resistance in a mixture of A(H1N1)pdm09 oseltamivir-sensitive/-resistant viruses. Furthermore, 3 laboratories (23%) considered oseltamivir-sensitive influenza B virus reduced susceptible/resistant.
CONCLUSIONS:
Detection of NA-H275Y in A(H1N1) viruses was achieved by most laboratories. IC(50) values and interpretation thereof varied for a sensitive/resistant virus mixture and for influenza B virus. The results of this exercise will assist harmonisation of antiviral susceptibility testing, interpretation and reporting within the European network through targeted training.
Copyright ? 2012. Published by Elsevier B.V.
PMID:
23201459
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/23201459