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of the American Medical Association, noted that the the current guidelines issued by the WHO and CDC are based on outdated models from the 1930s of how gas clouds from a cough, sneeze, or exhalation spread.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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Most Hopeless, Dumb and Irresponsible Home Minister in the History of Indian Govts.
This is diverting tactics from key issues, forget this ISIS this is not at all encouraged by Indian Muslims. This is BJP agenda to hide their Failure.
Government is quick on diverting minds of people....I don't think there are any ISIS in India.....to escape from the responsibility of safe guarding Dalits and minorities....this is the game gimmick....what a rubbish...
How can we believe these LIARs who have no shame in Fooling public again & again. The HM and Times now made an innocent decent guy as terrorist, just by quoting from a Bangladesh news paper (They apologized later) ... These LIARS have PHD in spreading LIES and making innocent a Terrorist. Recognise and be alert when you get news from these cheddis... Use your intellect and verify before you blame the innocent which may later find regretting for the action YOU take.
9 missing persons out of 20 crores.....PEA NUTS.... All the fingers of a hand are not equal.... After 5 years, the govt will come back and say, these were wrong reports by Police, as happened in the case of Akshamdam and Hyderabad attacks...
After 10 years everybody will be proved innocent..
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