Influenza molecular diagnostic testing in a 1000-bed academic Italian hospital during the 2018–19 influenza season

Aim: The aims of this study were to examine the requests for influenza molecular tests processed by the Virology Laboratory of the University Hospital of Udine during the 2018–19 influenza season and to assess the test results and to estimate costs. Subjects and methods: We analyzed various administrative databases of the hospital health information system, which can be deterministically linked at the individual level through an anonymous stochastic key. Requests for influenza molecular tests from November 1, 2018, to April 15, 2019, and test results were described by week and, for hospitalized patients, hospital ward. Previous vaccination status of tested patients, outcomes and estimated test costs were assessed. Results: In the 2018–19 influenza season, 979 influenza A and B virologic tests were processed by the laboratory, corresponding to 758 patients. Requests had more than doubled compared with the previous influenza season. Rapid real-time PCR tests, routinely available at the University Hospital of Udine since January 2019, represented 17% of requests. Six hundred forty-eight patients were hospitalized. Medical wards requested the test after a median of 1 day after admission, whereas requests were delayed for surgical and oncologic patients. The number of tests, proportion of positivity and consumption of rapid tests varied by medical specialty. Overall consumption of oseltamivir was similar to that of the previous influenza season. Conclusions: This analysis, benefiting from the availability of integrated health administrative databases, provided useful information to support public health decision-making and managing the supply and demand for diagnostic tests.