Six feet distancing not enough to stop coronavirus transmission in light winds: Study

News Network
May 20, 2020

London, May 20: The current physical distancing guidelines of 6 feet may be insufficient to prevent COVID-19 transmission, according to a study which says a mild cough in low wind speeds can propel saliva droplets by as much as 18 feet.

Researchers, including those from the University of Nicosia in Cyprus, said a good baseline for studying the airborne transmission of viruses, like the one behind the COVID-19 pandemic, is a deeper understanding of how particles travel through the air when people cough.

In the study, published in the journal Physics of Fluids, they said even with a slight breeze of about four kilometres per hour (kph), saliva travels 18 feet in 5 seconds.

"The droplet cloud will affect both adults and children of different heights," said study co-author Dimitris Drikakis from the University of Nicosia.

According to the scientists, shorter adults and children could be at higher risk if they are located within the trajectory of the saliva droplets.

They said saliva is a complex fluid, which travels suspended in a bulk of surrounding air released by a cough, adding that many factors affect how saliva droplets travel in the air.

These factors, the study noted, include the size and number of droplets, how they interact with one another and the surrounding air as they disperse and evaporate, how heat and mass are transferred, and the humidity and temperature of the surrounding air.

In the study, the scientists created a computer simulation to examine the state of every saliva droplet moving through the air in front of a coughing person.

The model considered the effects of humidity, dispersion force, interactions of molecules of saliva and air, and how the droplets change from liquid to vapour and evaporate, along with a grid representing the space in front of a coughing person.

Each grid, the scientists said, holds information about variables like pressure, fluid velocity, temperature, droplet mass, and droplet position.

The study analysed the fates of nearly 1,008 simulated saliva droplets, and solved as many as 3.7 million equations.

"The purpose of the mathematical modelling and simulation is to take into account all the real coupling or interaction mechanisms that may take place between the main bulk fluid flow and the saliva droplets, and between the saliva droplets themselves," explained Talib Dbouk, another co-author of the study.

However, the researchers added that further studies are needed to determine the effect of ground surface temperature on the behaviour of saliva in air.

They also believe that indoor environments, especially ones with air conditioning, may significantly affect the particle movement through air.

This work is important since it concerns safety distance guidelines, and advances the understanding of the transmission of airborne diseases, Drikakis said.

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News Network
May 9,2020

New Delhi, May 9: The Trinamool Congress on Saturday responded to Union home minister Amit Shah’s charge that the Mamata Banerjee-led West Bengal government is not facilitating the movement of stranded migrant workers.

Amit Shah has written to West Bengal chief minister Mamata Banerjee, saying her government is doing “injustice” to migrant workers by not allowing the special Shramik trains to reach the state.

“Union home minister Amit Shah speaks after weeks of silence only to mislead people with lies,” the TMC’s Abhishek Banerjee was quoted as saying by news agency PTI.

“The Centre is lying… West Bengal is running 711 camps for migrants in the state. We are taking good care of them,” Abhishek Banerjee, who is also the chief minister’s nephew, said.

Amit Shah had pointed out in his letter that the Centre was not receiving the “expected support” from the state government in helping stranded migrant workers from West Bengal.

“West Bengal government is not allowing trains with migrants reaching the state. This is injustice with WB migrant labourers. This will create further hardship for them,” Amit Shah had said in his letter to Mamata Banerjee.

The issue of migrant workers is the latest flashpoint between the Centre and the West Bengal government amid a row over the state’s efforts to control the coronavirus disease (Covid-19).

The Centre and the state have exchanged allegations over the criteria for reporting deaths from the infection, and while While Bengal says the Centre is trying to politicise a public health crisis, the Union government maintains that state officials are ignoring repeated warnings to step up the fight against the disease.

Federal officials have said that the region has not conducted adequate tests and that there has been mismanagement over identifying hotspots and containing them.

Union home secretary Ajay Bhalla also slammed the state government for a very low rate of testing and high rate of mortality, 13.2%, by far the highest for any state.

The Centre has also accused the state government of not allowing cross-border movement of goods trucks to Bangladesh.

There are 1,678 Covid-19 cases and 160 deaths in West Bengal until Saturday morning.

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News Network
February 9,2020

New Delhi, Feb 9: As the outbreak of novel coronavirus has lead to the death of more than 800 Chinese nationals, aviation regulator DGCA on Saturday said that foreigners who went to China on or after January 15 will not be allowed to enter India.

The DGCA, in its circular to airlines on Saturday, reiterated that all visas issued to Chinese nationals before February 5 have been suspended.

However, the Directorate General of Civil Aviation (DGCA) clarified, "These visa restrictions will not apply to aircrew, who may be Chinese nationals or other foreign nationalities coming from China."

"Foreigners who have been to China on or after January 15, 2020, are not allowed to enter India from any air, land or seaport, including Indo-Nepal, Indo-Bhutan, Indo-Bangladesh or Indo-Myanmar land borders," the DGCA said.

Among Indian airlines, IndiGo and Air India have suspended all of their flights between the two countries. SpiceJet continues to fly on Delhi-Hong Kong route.

On February 1 and 2, Air India conducted two special flights to Chinese city of Wuhan, epicentre of the outbreak, evacuating 647 Indians and seven Maldivians.

Till date, three Indians have tested positive for novel coronavirus.

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News Network
February 5,2020

Feb 5: Pakistan will buy more palm oil from Malaysia, Prime Minister Imran Khan said on Tuesday, aiming to help offset lost sales after top buyer India put curbs on Malaysian imports last month amid a diplomatic row.

India imposed restrictions on refined palm oil imports and informally asked traders to stop buying from Malaysia, the world's biggest producer of the edible oil. Sources said the move was in retaliation for Malaysia's criticism of India's policy on Kashmir.

Malaysian Prime Minister Mahathir Mohamad said on Tuesday that he discussed palm oil with Khan who was on a visit to Malaysia and that Pakistan had indicated it would import more from Malaysia.

"That's right, especially since we noticed India threatened Malaysia for supporting the Kashmir cause, threatened to cut palm oil imports," Khan told a joint news conference, referring to India's Muslim-majority region of Kashmir.

"Pakistan will do its best to compensate for that."

India is a Hindu-majority country while Malaysia and Pakistan are mainly Muslim. India and Pakistan have been mostly hostile to each other since the partition of British India in 1947, and have fought two of their three wars over competing territorial claims in Kashmir.

Pakistan may have bought around 135,000 tonnes of Malaysian palm oil last month, a record high, India-based dealers who track such shipments told Reuters on condition of anonymity.

The figure is close to estimates of 141,500 tonnes from Refinitiv, which show sales to India in January may have plunged 80% from a year earlier to 40,400 tonnes.

Malaysia will release official export data on Monday.

Pakistan bought 1.1 million tonnes of palm oil from Malaysia last year, while India bought 4.4 million tonnes, according to the Malaysian Palm Oil Council.

Malaysian palm oil futures rose on Tuesday after Khan's comments and on expectations of a steep drop in production in January.

STRONG TIES

India has repeatedly objected to Mahathir speaking out against its move last year to strip Kashmir's autonomy and make it easier for non-Muslims from neighbouring Muslim-majority Bangladesh, Pakistan and Afghanistan to gain citizenship.

At the news conference, Mahathir did not refer to Kashmir but Khan did.

"The way you, PM, have stood with us and spoken about this injustice going on, on behalf of Pakistan I really want to thank you," Khan said.

He also said he was sad he had been unable to attend a summit of Muslim leaders in Malaysia in December. Saudi Arabia did not attend the summit, saying it was the wrong forum to discuss matters affecting the world's Muslims and Khan belatedly pulled out.

Some Pakistani officials, unnamed because they were not authorised to speak to the media, said at the time that Khan pulled out under pressure from Saudi Arabia, a close ally, although local media reported his officials denied that was the reason for his absence.

"Unfortunately our friends, who are very close to Pakistan as well, felt that somehow the conference was going to divide the ummah," Khan said, using the Arabic word for the Muslim community but not mentioning Saudi Arabia by name.

"It is clearly a misconception, as that was not the purpose of the conference."

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