Impact of universal masking in health care and community on SARS CoV 2 spread

Universal masking the health care setting and in the community to contain the spread of SARS-CoV-2 has been recently recommended by the WHO, but supporting data are rare. The City of Jena was the first community in Germany to issue an order on mandatory public masking. Here, we report the development of the number of novel infections in our hospital and in the city of Jena after implementation of universal masking in our hospital and the city. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement MP was supported by a grant from the German Ministry of Education and Research (BMBF No. KI1501). MK was supported by the Integrated Research and Treatment Center, Center for Sepsis Control and Care (CSCC) at the Jena University Hospital, funded by the German Ministry of Education and Research (BMBF No. 01EO1502). ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: not applicable All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes The data that support the findings of this study are available from the corresponding author, [author initials], upon reasonable request.