ECDC publish external quality assessment scheme for Bordetella pertussis serology for 2020 data

10 May 2022

Article: 56/1805

The European Centre for Disease Prevention and Control (ECDC) has published a report presenting the results of the ECDC European Reference Laboratory Network for Pertussis (ERLNPert-Net) external quality assessment (EQA) scheme for Bordetella pertussis serology, conducted from April to September 2020. The EQA was organised by the National Institute for Biological Standards and Control (NIBSC) in the UK. 

The primary aim of this EQA scheme was to assess the ability of national reference laboratories in EU and EEA member states to correctly perform laboratory serodiagnostic tests for pertussis. This was achieved by assessing each participating laboratory’s ability to correctly measure the anti-pertussis toxin (anti-PT) immunoglobulin G (IgG) in sera samples and identifying any laboratories that are producing results significantly different from the values obtained from most participants. Furthermore, the scheme helped to identify methodologies in need of further improvement and areas for training, such as where particular laboratories may improve their methods, procedures and performance. 

Of the 31 laboratories that were invited to participate in the study, 17 agreed to take part. NIBSC sent blinded panels of eight freeze-dried sera samples containing different concentrations of anti-PT IgG to each of the 17 laboratories in 17 EU and EEA member states. The participating laboratories were asked to quantify concentrations of anti-PT IgG using their own routine diagnostic enzyme-linked immunosorbent assays (ELISA) or multiplex immunoassays (MIA), and raw data were also returned to NIBSC for secondary analysis. 

Of the 17 participating laboratories, one did not return results. Fifteen of the 16 laboratories that returned data used only one diagnostic method, either an in-house ELISA, an in-house MIA or a commercial ELISA kit to determine the anti-PT IgG concentrations of the sera panel. One laboratory submitted the results obtained using all three methods. A total of 57 data sets from individual assays were collected for 18 assay methods. 

Source: ECDC, 28 April 2022