JoePajak, 
Simulation study, led by @UKHSA researchers, suggests: 'COVID patient testing, isolation of ill healthcare workers, & universal HCW masking [Mar 2020 to Jul 2022] significantly reduced #SARSCoV2 transmission among patients & staff in UK hospitals.' @CIDRAP
https://www.cidrap.umn.edu/covid-19/covid-patient-testing-isolation-sick-staff-cut-hospital-viral-spread-modeling-study
