Quality control assessment of influenza and RSV testing in Europe: 2000-01 season

The Quality Control Assessment (QCA) was initiated to evaluate the quality of the influenza and respiratory syncytial virus (RSV) testing in the national reference centres belonging to the European Influenza Surveillance Scheme (EISS) network. Samples were coded and sent in two panels of 12 samples within a two week interval to 16 laboratories during the 2000-01 winter season. The antibodies titration by HI test was reported by 60% of the laboratories (n=16), and the results were correct for 56% of them. One false detection of influenza B antibodies was reported by one laboratory, and for the others the sensitivity varied widely. The sensitivity of the tests for the detection of influenza virus varied for A(H3N2) from 10 to 100 000 TCID50/ml. The influenza A subtyping was performed by 87% of the laboratories, and 31% gave correct results. The characterisation of the variants was undertaken by six laboratories and half of them fully achieved it. Fifty six percent of the laboratories used RT-PCR for the diagnosis; the results were specific and the sensitivity equivalent to the cell culture.