Coronavirus outbreak

Coronavirus lingers in rooms and toilets but disinfectants kill it: Study

A cleaner cleans the toilets at the hawker centre at Our Tampines Hub on Feb 16, 2020.
A cleaner cleans the toilets at the hawker centre at Our Tampines Hub on Feb 16, 2020.ST PHOTO: JASON QUAH

WASHINGTON • New research from Singapore's National Centre for Infectious Diseases and DSO National Laboratories has found that patients with the coronavirus 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 was published on Wednesday in the Journal of the American Medical Association and comes after cases in China where the pathogen spread extensively through hospitals, infecting dozens of healthcare workers and other patients. 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.

The Singapore researchers looked at 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, experiencing only 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.

The results, the authors wrote, "suggests the environment as a potential medium of transmission and supports the need for strict adherence to environmental and hand hygiene."


A version of this article appeared in the print edition of The Straits Times on March 06, 2020, with the headline 'Coronavirus lingers in rooms and toilets but disinfectants kill it: Study'. Subscribe