Improved performances of the second generation of the ID NOW influenza A&B 2(R) and comparison with the GeneXpert(R).

Due to the congestion of emergency wards, a rapid and accurate method for flu diagnosis is required. However, the first evaluations of the ID NOW(R) influenza AB (ii) Invalid rate per operator and time to result were calculated for the GeneXpert(R) Xpress Flu/RSV and the ID NOW(R) influenza A&B 2(R) during 2017-2018 and 2018-2019 flu outbreaks respectively. ID NOW(R) reaches an overall sensitivity and specificity of 96.6% and 96.1% respectively. Most of the false-negative display a CT > 37. For both instruments, a single operator was involved in about a half of all invalid results. Excluding this operator involved in most invalid result, the invalid rate was about 1% for both instruments. Time to result from sampling was significantly shorter in the ID NOW(R) versus the GeneXpert(R) group (33 vs 97 min, P < 0.01). The second generation of the ID NOW(R) influenza A&B 2 displays high performances, comparable with conventional PCR method. In order to prevent invalid results, we highlight the need for adequate training of operators. Also, when implemented in a central laboratory, the location of the instrument could have a strong impact on the time-to-results.