- Air moving in the same direction as cough increases COVID transmission
- Indian scientists said people should wear masks outside in response to the discovery
- Face masks have not been a legal requirement in England since July
Academics say that face masks should be worn outside when the wind is blowing to prevent the spread of Kovid.
Indian experts say that even a slight breeze can increase the chances of infected people spreading coronavirus.
Researchers from the Indian Institute of Technology Bombay simulated how far the coronavirus can spread in both calm and windy conditions.
The results showed that there was an ‘increased risk of infection’ even when there was a slight gust of five mph.
Lead author Professor Amit Agarwal said: ‘We recommend wearing a mask outdoors, especially in windy conditions.’
According to researchers from the Indian Institute of Technology Bombay, if an infected person coughs, even a small amount of air increases the transmission of the virus.
According to data from the Office for National Statistics, around 89 percent of Britons said they wore a face mask outside the home at the end of August. For comparison, in May it was 98 percent
Face masks have been implemented around the world as one of several restrictions to limit the spread of the virus, especially in crowded indoor spaces.
But throughout the pandemic there has been a heated scientific debate about how well guards work to reduce transmission.
Ministers dropped the legal requirement to wear coverings in England in July, when Number 10 led to ‘Independence Day’.
But people are encouraged to wear them in crowded places and some businesses – such as Transport for London – still require them.
The new study examined how COVID spreads through the air when someone coughs, using an equation designed to measure turbulence.
What are the rules of face covering?
In England, the legal requirement to wear a face mask was removed on 19 July.
But they must be worn in certain places such as public transport and shops in Scotland, Wales and Northern Ireland.
However, the government says people in England should continue to wear masks when they visit others indoors they don’t normally meet.
And its guidance states that patients and visitors continue to wear face coverings in all health care settings, such as hospitals and GP surgeries.
Masks are no longer required in classrooms in England, but some local authorities have asked schools to bring them back to control local outbreaks.
And as part of No 10’s ‘Plan B’ to control a fourth wave expected this winter, face coverings could become mandatory if the NHS comes under untenable pressure.
Earlier studies modeled a cough using gusts of air, but the researchers argued that an actual cough is more complex and can spin ‘like a mini whirlpool’.
They investigated how coughs spread under stationary conditions — compared to indoors — and at different wind speeds.
study, published in physics of fluids, showed that when an infected person coughs outside, the wind blowing in the same direction can spread the virus faster and further than in calm conditions.
Even a slight wind of five miles per hour (mph) spreads the virus by 20 percent in the direction someone is coughing.
This means that social distancing will have to be increased from 1 to 2 meters to 2.2 meters for it to be effective, the team found.
“At 9-11 mph (14-18 kph), the spread of the virus increases in distance and duration,” the researchers said.
Experts believe that longer projects project larger droplets into the air, reducing the amount of time it takes for the viral load in the air to dilute.
As the cough jet spreads through the air, infected aerosol droplets – which appear to be the major mode of COVID transmission – become ‘trapped’ in the air instead of quickly falling to the ground.
Professor Aggarwal said: ‘The study is significant in that it points to an increased infection risk that coughing can occur in the same direction as the wind can bring.
‘Increasing the residence time of a few large droplets will increase the viral load being transmitted via the cough jet and, therefore, increase the likelihood of infection.
‘Overall, the study found an increased likelihood of infection even in the presence of light wind.’
What have studies found about face masks and COVID?
Research on how well different types of masks and face coverings protect against the coronavirus varies, but experts and politicians have generally leaned toward the idea that some protection is likely better than none.
In the UK, face coverings were made mandatory first for public transport in June and later in July for shops and other indoor spaces.
The studies so far about whether masks work or not have shown:
Face Masks Lower Virus R Rate (January 2021)
Researchers from Boston University in the US found that wearing a face mask is an effective way to prevent the spread of coronavirus.
This study published in the journal Lancet Digital HealthA 10 percent increase in self-reported mask wear is associated with a threefold increase in the odds of keeping the R number — the number of people infected with the coronavirus — below 1.
Study co-author Ben Rader, from Boston Children’s Hospital and Boston University, said: ‘An important finding of this research is that wearing a mask is not a substitute for physical distancing.’
Infectious droplets will still slip (December 2020)
Scientists at New Mexico State University in the US found that wearing a cloth mask may not completely protect the user from the coronavirus as infected droplets can slip through, but will significantly reduce it.
Dr Krishna Kota, an associate professor at the university who led the research, said: “Wearing a mask will provide adequate protection to a susceptible person, but not complete.”
The study found that when all masks block at least 95 percent of droplets from coughing and sneezing—there was still a risk of infection.