WASHINGTON - AFP: New research from Singapore shows that patients with the novel coronavirus (COVID-19) extensively contaminate their bedrooms and bathrooms, underscoring the need to routinely clean high-touch surfaces, basins and toilet bowls.
The virus was however killed by twice-a-day cleaning of surfaces and daily cleaning of floors with a commonly used disinfectant, suggesting that current decontamination measures are sufficient as long as people adhere to them.
The research letter was published in the Journal of the American Medical Association (JAMA) on Wednesday 4 March 2020 and comes after cases in China where the pathogen spread extensively through hospitals, infecting dozens of health care workers and other patients.
This led scientists to believe that, beyond catching the infection through coughing, environmental contamination is 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.
The patient whose room was sampled before cleaning had the mildest symptoms of the three, only experiencing a cough. The other two had moderate symptoms: both had coughing and fever, one experienced shortness of breath and the other was coughing up mucus.
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 when tested for the coronavirus.
"Significant environmental contamination by patients with SARS-CoV-2 through respiratory droplets and faecal 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.