As Omicron’s rapid spread rendered individual testing too slow to track and control the virus, Aaron Hinz and Rees Kassen of the University of Ottowa sought new strategies for watching it. Wastewater sampling has proven a useful method of detecting the virus in the environment rather than in individuals, providing early warning signs. Hinz and Kassen’s surface testing may unlock similar information in smaller settings like rooms within schools, health facilities or workplaces.
They began swabbing walls, surfaces, handrails and floors in hospital COVID-19 wards, to understand if positive samples could be compared to understand where the virus particles were more abundant. Comparing results from COVID-19 wards and non-COVID-19 wards from two hospitals over 10 weeks, they detected the virus, which was rarely found on walls and surfaces but commonly found on floors, and recovered the virus more frequently from the floors of COVID wards than from non-COVID wards.
The test results, say the pair, tell us that by sampling floors we can identify locations where infected persons may have been present. They are now expanding their study to long-term care homes, schools and childcare facilities. “Preliminary results are promising: floor samples can detect the virus up to a week before cases are reported in some of these facilities,” they say in a Conversation article, “If these results hold up, we will have a new tool to guide us in managing a safe return to life.”