This led scientists to believe that, beyond catching the infection through coughing, environmental contamination was an important factor in the disease’s transmission, but its extent was unclear.
Researchers at Singapore’s National Centre for Infectious Diseases and DSO National Laboratories looked at the cases of three patients who were held in isolation rooms between late January and early February. They collected samples from their rooms on five days over a two-week period.
The room of one patient was sampled before routine cleaning, while the rooms of the other two patients were sampled after disinfection measures.
Site Test Findings
Despite this disparity, the patient whose room was sampled before cleaning contaminated 13 of 15 room sites tested, including a chair, the bed rail, a glass window, the floor, and light switches.
Three of the five toilet sites were also contaminated, including the sink, door handle and toilet bowl – more evidence that stool can be a route of transmission.
Air samples tested negative, but swabs taken from air exhaust outlets were positive – which suggests that virus-laden droplets may be carried by air flows and deposited on vents.
The two rooms that were tested after cleaning had no positive results.
“Significant environmental contamination by patients with Sars-CoV-2 through respiratory droplets and fecal shedding suggests the environment as a potential medium of transmission and supports the need for strict adherence to environmental and hand hygiene,” the authors wrote, using the official name of the pathogen.