Introduction: The reasons for the decrease in blood cultures were investigated and the rate and aetiology of bacteremia and contaminated blood cultures collected from COVID and non-COVID patients were assessed.

Methods: We performed a retrospective analysis in a tertiary hospital in Spain during the COVID period from 4th March 2020 to 21thJune 2020.Results: The number of blood cultures processed was 5313, representing 22.7% and 18.8% of decrease compared to the same months of 2019 and 2018, respectively (p=0.173). The rate of bacteremia was 1.2% higher among COVID-patients than among non-COVID patients (p <0.001). COVID patients had a higher proportion of nosocomial bacteremia (95.5 %) than non-COVID patients (30.5 %) (p <0.001). In COVID-positive patients, the contamination rate was 12.3% vs 5.7% in non-COVID patients (p <0.001).Conclusion: There was a decrease in the number of blood cultures collected during the COVID period compared to previous years . Bacteremia in COVID patients was mainly nosocomial and catheter-related.