“…The retrospective nature of our case-control study precludes conclusions There have been many reports on hospital-based outbreaks of COVID-19 [4, 25, 27-29, 31, 39, 52-56], however a strength of our report is that it incorporated a case-control study to explore contributing ward and patient-related factors to the acquisition of COVID-19, occurring in a setting without vaccination for any HCWs or patients. Our outbreak has similarities with other COVID-19 nosocomial outbreaks including unidentified cases on a ward [39,56], positive HCWs who may have sub-optimal adherence to IPC measures [52,54], and the role of multi-bedded rooms in SARS-CoV-2 transmission [27,29,31,34,35] Further, our report included patient symptoms, environmental sampling, whole genome sequencing, viral culture and has identified the novel finding of fluid and electrolyte disorders increasing the likelihood of COVID-19 acquisition.…”