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
February 6,2020

Washington, Feb 6: The US has expressed concern over the current situation of religious freedom in India and raised the issue with Indian officials, a senior State Department official has said.

The remarks came in the wake of widespread protests held across India against the Citizenship Amendment Act (CAA).

The senior State Department official, on condition of anonymity, said that he has met with officials in India about what is taking place in the nation and expressed concern.

"We are concerned about what's taking place in India. I have met with the Indian foreign minister. I've met with the Indian ambassador (to express my concern)," the official, who was recently in India, told reporters on Wednesday.

The US has also "expressed desire first to try to help and work through some of these issues", the official said as Secretary of State Mike Pompeo launched a 27-nation International Religious Freedom Alliance.

"To me, the initial step we try to do in most places is say what can we do to be of help you work through an issue to where there's not religious persecution. That's the first step, is just saying can we work with you on this," the official said.

India maintains that the Indian Constitution guarantees fundamental rights to all its citizens, including its minority communities.

It is widely acknowledged that India is a vibrant democracy where the Constitution provides protection of religious freedom, and where democratic governance and rule of law further promote and protect fundamental rights, a senior official of the Ministry of External Affairs has said.

According to the CAA, members of Hindu, Sikh, Buddhist, Jain, Parsi and Christian communities who have come from Pakistan, Bangladesh and Afghanistan till December 31, 2014 following religious persecution there will get Indian citizenship.

The Indian government has been emphasising that the new law will not deny any citizenship rights, but has been brought to protect the oppressed minorities of neighbouring countries and give them citizenship.

Defending the CAA, Prime Minister Narendra Modi last month said that the law is not about taking away citizenship, it is about giving citizenship.

"We must all know that any person of any religion from any country of the world who believes in India and its Constitution can apply for Indian citizenship through due process. There's no problem in that," he said.

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News Network
June 13,2020

Jun 13: Requiring the wearing of masks to prevent the spread of the novel coronavirus in areas at the epicenter of the global pandemic may have prevented tens of thousands of infections, a new study suggests.

Mask-wearing is even more important for preventing the virus' spread and the sometimes deadly COVID-19 illness it causes than social distancing and stay-at-home orders, researchers said, in the study published in PNAS: The Proceedings of the National Academy of Sciences of the USA.

Infection trends shifted dramatically when mask-wearing rules were implemented on April 6 in northern Italy and April 17 in New York City - at the time among the hardest hit areas of the world by the health crisis - the study found.

"This protective measure alone significantly reduced the number of infections, that is, by over 78,000 in Italy from April 6 to May 9 and over 66,000 in New York City from April 17 to May 9," researchers calculated.

When mask-wearing went into effect in New York, the daily new infection rate fell by about 3% per day, researchers said. In the rest of the country, daily new infections continued to increase.

Direct contact precautions - social distancing, quarantine and isolation, and hand sanitizing - were all in place before mask-wearing rules went into effect in Italy and New York City. But they only help minimize virus transmission by direct contact, while face covering helps prevent airborne transmission, the researchers say.

"The unique function of face covering to block atomization and inhalation of virus-bearing aerosols accounts for the significantly reduced infections," they said. That would indicate "that airborne transmission of COVID-19 represents the dominant route for infection."

The U.S. Center for Disease Control and Prevention on Friday urged organizers of large gatherings that involve "shouting, chanting or singing to strongly encourage the use of cloth face coverings to lower the risk of spreading the coronavirus."

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News Network
February 6,2020

Beijing, Feb 6: The number of confirmed fatalities from China's coronavirus outbreak rose to at least 560, after authorities in hardest-hit Hubei province reported 70 new deaths on February 6.

In its daily update, the health commission in Hubei also confirmed the number of confirmed infections in the outbreak has reached 28,018 nationwide with 3,694 new cases reported.

The epidemic, which has spiralled into a global health emergency, is believed to have emerged in December from a market that sold wild game in Hubei's capital Wuhan.

Hu Lishan, an official in Wuhan, warned Wednesday that despite building a hospital from scratch and converting public buildings to accommodate thousands of extra patients, there was still a "severe" lack of beds in the region.

There was also a shortage of "equipment and materials," he told reporters, adding that officials were looking to convert other hotels and schools in the city into treatment centres.

Authorities in several other cities in China have placed restrictions on the number of people allowed to leave their homes.

Global concerns have also risen about the virus, with cases confirmed in more than 20 countries.

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