A cheap acid which has been sprayed on streets and surfaces across the world may be a key ingredient behind low infection rates.
For months officials in countries such as China, Japan and Hong Kong have been busy dousing public places in hypochlorous acid.
The substance, which is known as HCIO, is formed by dissolving chlorine in water, and is dozens of times more effective at killing viruses than bleach.
It is also incredibly cheap to produce.
Despite having helpful cleansing properties, the acid is weak enough to pose little threat to humans and is used to keep swimming pool water clean.
Earlier this week the UK government approved trials which will see HCIO sprayed in public places.
The fact the use of the liquid has taken so long to be used in the UK, when its effectiveness elsewhere has been apparent for months, has been questioned by experts.
Dr Darren Reynolds, professor in Health and Environment at the University of the West of England, told MailOnline: “We should have used HOCl from the very start.
“It would have made a huge difference – but it’s still not too late.”
HOCI has been used to great effect in South Korea and has been praised as a key reason why the country has kept its coronavirus cases low.
Not only is the liquid sprayed on the streets, people entering and exiting certain public places have been doused in a mist of HOCI.
Workers heading home at the end of shifts have been walking through arches which blast hypochlorous acid from the sides.
The practice is not unheard of in the UK, where dental workers use hand held spray guns to kill bacteria and viruses on surfaces.
Rugby and football clubs may soon be getting in on the act.
Trimite, a company which distributes fogging tunnels, says it is “in discussions” with some clubs to have their products installed.
The company’s chairman David Roberts told MailOnline: “There will be some queuing but it will take no longer to walk through a fogging tunnel than it will to go through a turnstyle where you have to show your ticket.”
The business chief said he is talking to the NHS to have the disinfectant machines installed at the entrances of hospitals.