Research that was due to be presented at this year’s European Congress on Clinical Microbiology and Infectious Diseases shows that using paper towels is substantially more effective than jet dryers for removing microbes when still contaminated hands are dried.
Hand drying is important to minimize the spread of dangerous microbes, including the novel coronavirus, since failure to remove them increases transfer to environmental surfaces and increases the opportunities for transmission and spread. In this study, the authors investigated whether there are differences in extent of virus transmission, according to hand drying method, beyond the toilet/washroom to the hospital environment. Researchers Ines Moura of the University of Leeds, UK, and colleagues Duncan Ewin and professor Mark Wilcox, from the University of Leeds and Leeds Teaching Hospitals NHS Trust, collaborated on the project.
Four volunteers simulated contamination of their hands/gloved hands using a bacteriophage (which is a virus that infects bacteria and so is harmless to humans). Their hands were not washed after contamination to simulate inadequately washed hands. Hands were dried using either paper towels (PT) or a jet air dryer (JAD). Each volunteer wore an apron, to enable measurement of body/clothing contamination during hand drying. Hand drying was performed in a hospital public toilet and, after exiting, samples were collected from public and ward areas.
Surface sites were sampled following contact with hands or apron. The sites samples were doors, stairs handrails, lift buttons, chairs in public and ward areas, phones, buttons on access intercoms to wards, stethoscope tubing, stethoscope head piece and chest piece, the aprons themselves, and armchairs that had been indirectly in contact with the apron. For the latter, volunteers were asked to cross their arms across their chest while using the apron, before resting on the arms of the chair.
The authors conclude: “There are clear differences, according to hand drying method, in the residual microbial contamination of the subject’s hands and body. Crucially, these differences in contamination translate into significantly greater levels of microbe contamination after jet air drying versus paper towel use from hands and body beyond the toilet/washroom. As public toilets are used by patients, visitors and staff, the hand drying method chosen has the potential to increase (using jet dryers) or reduce (using paper towels) pathogen transmission in hospital settings.”