As news of the coronavirus first surfaced, everyone scrambled to purchase surgical masks in large numbers. However, the CDC issued a statement that surgical masks are not enough as protection against coronavirus as infected patients can contaminate any surface they touch. After the statement by CDC, surface disinfectants, hand sanitizers, and cleaning supplies have been walking off the shelves. People have become cautioned repeatedly against touching surfaces in public places such as subways, restaurants, and shopping marts.
Touching surfaces contaminated with the virus using your bare hands followed by touching your eyes, nose or mouth can easily transmit the virus. However, washing your hands after touching any surfaces and disinfecting all potentially infected surfaces such as kitchen tables, bathroom sinks, and mobile phones is highly effective to prevent transmission of coronavirus through contaminated surfaces.
Varying reports regarding the survival rate of coronavirus on surfaces have confused people quarantined at home. Reports from China claimed that the virus can survive on doorknobs for approximately 5 days. According to new research published in The New England Journal Of Medicine, the virus can survive in room air for 4 hours, on cardboards or wooden boards for 24 hours, and on metallic surfaces for 3 days.
There have been numerous studies regarding older strains of Coronavirus and their duration of viability on external surfaces. Comparing the reports of all studies, if the COVID-19’s survival on external surfaces is similar to other strains of coronavirus, SARS, and MERS then it can remain viable on glass, plastic, or metals for up to nine days whereas the Influenza virus can survive for only two days on any surfaces.
However, at temperatures higher than 86 degrees Fahrenheit (30 degrees Celsius), most of the virus becomes incapacitated. Additionally, they can be easily destroyed by most household surface disinfectants by simply wiping the surfaces. According to the CDC, an effective disinfectant must contain at least 70% ethanol, 0.1 % Sodium Hypochlorite, or 0.5% hydrogen peroxide to significantly sterilize surfaces.
These reports are all based on older research of related strains of COVID-19, therefore currently it is impossible to know if simply heating or sterilizing surfaces can completely eradicate the virus from surfaces. As per CDC guidelines, sodium Hypochlorite(bleach) can be used as a disinfectant by diluting it with water (5 tablespoons per gallon of water). However, mixing bleach with other types of cleanser or ammonia can produce toxic fumes, so they should always be used separately and not mixed.
Although surface contamination is not the main pathway for virus spread, it is still an important and easily preventable pathway. Other means of infection such as contaminated air may be more difficult to be protected from.
The major route of transmission is through respiratory droplets and close contact which is best prevented by avoiding contact with any infected people by self-quarantine. Disinfecting household surfaces is particularly important for families with a suspected case of COVID-19 within the family. In such households, all surfaces such as light switches, doorknobs, remotes, toilets, sinks, kitchen tables, chairs, and mobiles should be thoroughly disinfected regularly.