J Hosp Infect. 2019 Feb 2. pii: S0195-6701(19)30055-6. doi: 10.1016/j.jhin.2019.01.025. [Epub ahead of print] Humphreys H1, Coleman DC2. Author information 1 Department of Clinical Microbiology, The Royal College of Surgeons in Ireland, Ireland; Department of Microbiology, Beaumont Hospital, Dublin Ireland. Electronic address: hhumphreys@rcsi.ie.2 Microbiology Research Unit, Dublin Dental University Hospital, Trinity College Dublin, University of Dublin, Dublin, Ireland.