Saturday, 4 April 2020

Speech, an important part of Coronavirus infection - Indians need to be extra careful!!

www.downtoearth.org.in
thriveglobal.com
World over almost all political leaders/ heads  keep advising people to maintain social distancing and self-isolation  in a lock-down situation to retard the spreads of covid-19 that increases exponentially once it strikes an area. Now, the world-wide toll is more than 60,000 and 1.1 million people have been infected by the virus and medical experts are keeping their fingers crossed as to when its ferocity will come to an  end and the world will be relieved of all pains, suffering and death.
  In India the infection is  gradually picking up and in many states people fail to follow the guidelines. The recent mass gathering of Muslims in Delhi (March, 2020) despite  the government's warning is a cause for concerns among  Indians. Recently, in south Tamil Nadu, though the state is under lock down till 14th April, several hundred people, including youths gathered in a mosque and were forced by the police to disperse them. A section of the people have not yet understood the savagery of this dangerous virus and its impact on the society as whole.    

With no cure in sight,  social distancing is the only  option we have  to avoid pushing ourselves into a precarious position in the next few weeks from which redemption is difficult.  Regarding corona infection, yet another important fact that we may not be aware of is our speech also plays a key role in spreading infection  among people in close physical contact. Please read the article below:

According to aerosol scientists,  social-distancing has an added advantage in controlling infection. They are of the view that  normal speech by individuals who are asymptomatic but infected with coronavirus may produce enough aerosolized particles to transmit the infection. Though the link between the  spread of virus and normal speech is not scientifically proven, it is imperative to emphasis strict social distancing measures for virologists, epidemiologists and engineers who study aerosols and droplets to work together on this and other  respiratory diseases.

William Ristenpart, professor of chemical engineering at UC, Davis, USA says  ordinary speech creates significant quantities of aerosols from respiratory particles as you may be aware aerosols are particles small enough to travel through the air. These respiratory particles  too small to see  with the naked eye  - about one micron, or one micrometer, in diameter;  but, are  large enough to carry viruses such as influenza or SARS-CoV-2.

Last year, Ristenpart,  his graduate student and colleagues published a paper in which they mentioned that  'the louder one speaks, the more particles are emitted and that some individuals are "superemitters" who give off up to 10 times as many particles as others', depending on the nature of their voice and its modulation.  In a follow-up study published in January last year in PLOS One, they  went deeper and investigated which 'speech sounds are associated with the most particles'.

Calculating just how easily a virus like SARS-CoV-2 spreads through droplets  is a difficult one and it needs knowledge of other related fields.  Virologists need to know how many viruses are present in the lung fluid and how many of them form into droplets  and how many viruses are needed to form an infection. Aerosol scientists can study the travel mechanism of such droplets once they are out of our body. They need to know how far once expelled,  the droplets travel, how they are affected by air motion in a room and how fast they settle out  due to gravity.

Ristenpart and colleagues conclude. "The aerosol science community needs to step up and tackle the current challenge presented by COVID-19, and also help better prepare us for inevitable future pandemics,"
en.wikipedia.org
 In countries like India natives speak  a lot and many in a loud manner. So social distancing coupled  with  silence  (zipped-up mouth) will help us a lot in controlling the virus.  The Nizamuddin (Delhi) gathering by the Muslims - the Tablighi Jamaat, in which more than 3000 people gathered in the second  week of March defying  central government's lock-down order  and their mingling with  many corona-infected world religious leaders has  become a subject of debate because this gathering  already impacted the spread of the virus in many states, the most affected being Tamil Nadu. What we need is discretion in this hour of horrible pandemic and it is the responsibility of every citizen to follow the Govt. guidelines. Think about your family, children and people in your neighborhood. 
Tit-bits: 
 An aerosol (abbreviation of "aero-solution") is a suspension of fine solid particles or liquid droplets in air or another gas. Aerosols can be natural or anthropogenic. Natural aerosols are fog, mist, dust, forest exudates and geyser steam.  Anthropogenic aerosols are particulate air pollutants and smoke. The liquid or solid particles
Mist and clouds are natural aerosols  commons.wikimedia.org
have diameters typically less than 1 μm; larger particles with a significant settling speed make the mixture a suspension, but the distinction is not clear-cut. In common parlance aerosol refers to an aerosol spray that delivers a consumer product from a can or similar container. .... (https://en.wikipedia.org/wiki/Aerosol)

https://www.sciencedaily.com/releases/2020/04/200403162709.htm
(April 03, 2020 from Materials provided by University of California - Davis. Original written by Andy Fell)