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of the American Medical Association, noted that the the current guidelines issued by the WHO and CDC are based on outdated models from the 1930s of how gas clouds from a cough, sneeze, or exhalation spread.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
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Unempolyment and farmer death are the issues gifted on us by the central BJP government from demonitisation and GST. Now our PM friends Donald trumps administration also accepted that due to this two isssues Indias growth has been slow for more then a year now.
Unemployment of whom ? Siddaramaiah claims 15 lakhs jobs have been created but has yedduyurappa the guts to ask how many native Kannadigas got the job ?
Regarding cauvery why he did not even open his mouth on SC judgment .
Was there a gag order from Delhi high command. He did not have guts to even welcome the judgment. Probably he knows it was outright injustice to Karnataka but he is helpless and is concerned about his career ! Of course Cong & JD-S also did not have the guts.
Regarding atrocities on women nothing prevents Modi govt. making stringent laws and Karnataka will definitely welcome it. But Modi is too busy with "Man ki bath " , Foreign tours. All he knows is vandemataram & Yoga and of course mudslinging on congress which anyway it rightly deserves.
So native Kannadigas reject the three parties BJP, Cong & Jd-S and
and bring a Kannada party to power or follow the crowd like fools
and dig your own grave. Ignore all the posts of migrants & traitors .
No Unemployment and Farmers suicide in BJP ruled states.
infants,Mothers,Women,Girls, Pregnant women are being Raped, burnt and killed alive. and you are talking about women safety.
Protection of wives is also a key issue.
You said truth but a small correction needed. These are the key issues to highlight only for election..
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