Getting the disinfectant onto the right surfaces, surfaces which people are likely to touch a lot, in the correct concentration to kill the organism, and in a way that doesn’t cause additional safety risks to workers or the public can be challenging. Sanitation workers have been seen around the world spraying public places including streets, parks and plazas of the cities hardest hit by the new novel coronavirus with disinfectant. According to various local news reports from cities across Asia, the disinfectant most commonly used outdoors is a diluted solution of sodium hypochlorite, which is also known as bleach. However, widespread disinfection using bleach can be harmful to those exposed to it.
Bleach comes with inherent difficulties in our ability to apply it effectively to high-touch surfaces, and it also has safety implications for workers spraying the disinfectant and also for members of the public who come into contact with the spray. Bleach can burn the skin and eyes, which is why people spraying it usually wear protective equipment. It can also trigger respiratory conditions among those who are often exposed to it.
It can be effective in the right circumstances and as part of a comprehensive approach to control and prevention. It would work in situations where you can have the workers protected with personal protective equipment and the spray is being applied in a confined space that is vacant such as on buses and streetcars.
Outdoor surfaces, such as roads, squares, lawns, should not be sprayed with bleach repeatedly. Extensive use may cause environmental pollution and should be avoided.
It is not known whether bleach destroys the COVID-19 virus outside as it does on indoor surfaces because scientific research has yet to be done on the issue.
According to the New England Journal of Medicine, the novel coronavirus can live on different surfaces for a few hours or up to several days if touched by an infected person, some of whom show no symptoms.
Bleach is commonly used in disinfectants because of its ability to break down virus proteins — the basic units that keep the virus functioning. Alcohols can also disrupt the fatty outer membrane that coats many viruses, including the COVID-19 virus, which prevents them from latching onto human cells and replicating.
The World Health Organization (WHO) says studies suggest that the coronavirus cannot be transmitted by air. The respiratory droplets responsible for spreading the virus are too heavy to stay suspended in the air, instead of falling onto the floor and nearby objects and surfaces right away.
Disinfectants like bleach seem to be effective in killing coronaviruses. However, any measure like this has to be used in conjunction with a range of prevention measures — it is not effective if this is the only thing that is done.
Transmission of the coronavirus most commonly comes from breathing in respiratory droplets sent into the air when an infected person coughs or sneezes.
As coronaviruses are spread from people to people, the most important measure is to stop transmitting the virus through coughing, sneezing, breathing on each other in close proximity. Applying a disinfectant to surfaces that are likely to be touched, can be an additional way to stop transmission.