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Toscana, West Nile, Usutu and tick-borne encephalitis viruses: external quality assessment for molecular detection of emerging neurotropic viruses in Europe, 2017
- Chantal Reusken1,2 , Cecile Baronti3 , Ramona Mögling1 , Anna Papa4 , Katrin Leitmeyer5 , Remi N Charrel3
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View Affiliations Hide AffiliationsAffiliations: 1 Department of Viroscience, Erasmus University Medical Centre, Rotterdam, the Netherlands 2 Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands 3 Unite des Virus Emergents (UVE: Aix Marseille Univ, IRD 190, INSERM 1207, IHU Mediterranee Infection), Marseille, France 4 Department of Microbiology, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece 5 European Centre for Disease Prevention and Control (ECDC), Solna, SwedenRemi N Charrelremi.charrel univ-amu.fr
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Citation style for this article: Reusken Chantal, Baronti Cecile, Mögling Ramona, Papa Anna, Leitmeyer Katrin, Charrel Remi N. Toscana, West Nile, Usutu and tick-borne encephalitis viruses: external quality assessment for molecular detection of emerging neurotropic viruses in Europe, 2017. Euro Surveill. 2019;24(50):pii=1900051. https://doi.org/10.2807/1560-7917.ES.2019.24.50.1900051 Received: 13 Jan 2019; Accepted: 13 Jun 2019
Abstract
Neurotropic arboviruses are increasingly recognised as causative agents of neurological disease in Europe but underdiagnosis is still suspected. Capability for accurate diagnosis is a prerequisite for adequate clinical and public health response.
To improve diagnostic capability in EVD-LabNet laboratories, we organised an external quality assessment (EQA) focusing on molecular detection of Toscana (TOSV), Usutu (USUV), West Nile (WNV) and tick-borne encephalitis viruses (TBEV).
Sixty-nine laboratories were invited. The EQA panel included two WNV RNA-positive samples (lineages 1 and 2), two TOSV RNA-positive samples (lineages A and B), one TBEV RNA-positive sample (Western subtype), one USUV RNA-positive sample and four negative samples. The EQA focused on overall capability rather than sensitivity of the used techniques. Only detection of one, clinically relevant, concentration per virus species and lineage was assessed.
The final EQA analysis included 51 laboratories from 35 countries; 44 of these laboratories were from 28 of 31 countries in the European Union/European Economic Area (EU/EEA). USUV diagnostic capability was lowest (28 laboratories in 18 countries), WNV detection capacity was highest (48 laboratories in 32 countries). Twenty-five laboratories were able to test the whole EQA panel, of which only 11 provided completely correct results. The highest scores were observed for WNV and TOSV (92%), followed by TBEV (86%) and USUV (75%).
We observed wide variety in extraction methods and RT-PCR tests, showing a profound absence of standardisation across European laboratories. Overall, the results were not satisfactory; capacity and capability need to be improved in 40 laboratories.
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