The current physical distancing guidelines provided by the World Health Organisation (WHO) and by the US Centers for Disease Control and Prevention (CDC) may not be adequate to curb the coronavirus spread, according to a research which says the gas cloud from a cough or sneeze may help virus particles travel up to 8 metres. The research, published in the Journal of the American Medical Association, noted that the the current guidelines issued by the WHO and CDC are based on outdated models from the 1930s of how gas clouds from a cough, sneeze, or exhalation spread.
Study author, MIT associate professor Lydia Bourouiba, warned that droplets of all sizes can travel 23 to 27 feet, or 7-8 metres, carrying the pathogen.
According to Bourouiba, the current guidelines are based on "arbitrary" assumptions of droplet size, "overly simplified", and "may limit the effectiveness of the proposed interventions" against the deadly pandemic.
She explained that the old guidelines assume droplets to be one of two categories, small or large, taking short-range semi-ballistic trajectories when a person exhales, coughs, or sneezes.
However based on more recent discoveries, the MIT scientist said, sneezes and coughs are made of a puff cloud that carries ambient air, transporting within it clusters of droplets of a wide range of sizes.
Bourouiba warned that this puff cloud, with ambient air entrapped in it, can offer the droplets moisture and warmth that can prevent it from evaporation in the outer environment.
"The locally moist and warm atmosphere within the turbulent gas cloud allows the contained droplets to evade evaporation for much longer than occurs with isolated droplets," she said.
"Under these conditions, the lifetime of a droplet could be considerably extended by a factor of up to 1000, from a fraction of a second to minutes," the researcher explained in the study.
The MIT scientist, who has researched the dynamics of coughs and sneezes for years, added that these droplets settle along the trajectory of a cough or sneeze contaminating surfaces, with their residues staying suspended in the air for hours.
"Even when maximum containment policies were enforced, the rapid international spread of COVID-19 suggests that using arbitrary droplet size cutoffs may not accurately reflect what actually occurs with respiratory emissions, possibly contributing to the ineffectiveness of some procedures used to limit the spread of respiratory disease," Bourouiba wrote in the study
Comments
Rakesh... dont tell us that all those chant VM are Nationalists
And you cant force people to chant this....
Ibraheem Hussain, Udupi, any comments.
This is sad and not right at all , brothers fighting against each other. Those guys dont represent me .
I apology and prayer to the cop.
Walida-e-hind-ki Zindabad :)
Shave BABA RAMDEVS BEARD....very good to know he rejected say ---mantaram.
They never targetted him , this police man objected for vande mataram , so they thrashed him . so CD is misleading its readers .
I did not see any chaddi statement now. Is it tolerenance?
Shocking, the Great India is turning to intolerant India! credit goes to rulers of India and its state.
ONE WHO VOTED TO MODHIJII ACCHE DINNN LET THEM SEE THIS AND SELECT THIER FUTURE.
THIS PEOPLE FRIST SHAVE U R SWAMIJI BEARED THEN US....
MODHIJI IS FAKEJIIII
Acche din effect
Now Arnab will shout in Newshour that the Muslim policemen is an anti national.
Modi government has already gave all the RSS to take the law into their hand. May be one day will come that our nation will become like Pakistan and Afghanistan; if not controlled by these RSS mad dogs.
The Roots of EVIL : ARROGANCE; ENVY and GREED.
Knowledge makes people HUMBLE
Arrogance make people IGNORANT.
I think there are many Ignorants who say they are the superior . but they really are stupids and commit such acts which they themselves open the door of hell.
THIS IS ACHEE DEEN OF MODI
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