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
June 16,2020

Beijing, Jun 16: The coronavirus situation in China's capital is "extremely severe", a city official warned Tuesday, as 27 new infections were reported from Beijing where a new cluster has sparked a huge trace-and-test programme.

The COVID-19 resurgence -- believed to have started at the sprawling Xinfadi wholesale food market in the capital -- has sparked alarm as China had largely brought its outbreak under control through mass testing and lockdowns imposed earlier in the year.

The new cases took the number of confirmed infections in Beijing over the past five days to 106, as authorities locked down almost 30 communities in the city and tested tens of thousands of people.

"The epidemic situation in the capital is extremely severe," Beijing city spokesman Xu Hejian warned at a press conference.

The World Health Organization had already expressed concern about the cluster, pointing to Beijing's size and connectivity.

Officials in the capital have said they will test stall owners and managers at all of the city's food markets, restaurants and government canteens.

Beijing's coronavirus testing capacity has been expanded to 90,000 a day, according to China's official news agency Xinhua.

On Tuesday, the capital's transport commission banned taxi- and ride-hailing services from driving out of the city, Xinhua reported, in another move to try and contain the new outbreak.

All indoor sports and entertainment venues in Beijing were ordered to shut on Monday, and some other cities across China warned they would quarantine those arriving from the capital.

The National Health Commission also reported four new domestic infections in Hebei province, which surrounds Beijing, and a case reported in southwestern Sichuan province was linked to the Beijing cluster.

Authorities were also racing to track people from Beijing who had travelled to other parts of China, and those who visited the capital have been encouraged to get tested.

Beijing spokesman Xu said: "High-risk people who have left Beijing must inform local authorities immediately."

Market inspections

Authorities shut down another market on Tuesday -- Tiantaohonglian in the central Xicheng district -- after one employee there was diagnosed with COVID-19, state broadcaster CCTV reported.

Seven residential estates surrounding that market were also locked down.

In total, Beijing officials said Tuesday they have disinfected 276 agricultural markets, closed 11 markets, and disinfected more than 33,000 food and beverage businesses in a bid to stamp out the new cluster.

Officials had warned Sunday that since May 30, 200,000 people had visited the Xinfadi market -- the original site of the new outbreak.

More than 8,000 workers from Xinfadi have been tested and sent to centralised quarantine facilities.

Until this recent outbreak, most of China's cases in recent months were nationals returning home as the pandemic spread to other countries.

China's Center for Disease Control and Prevention said Monday that the virus strain found in the Beijing outbreak was a "major epidemic strain in the European countries".

While the virus was detected on chopping boards used to handle imported salmon at Xinfadi, "it does not clearly or definitely indicate it's from imported seafood", Wu Zunyou, the body's chief epidemiologist, said in an interview with state broadcaster CCTV.

"Ever since new cases suddenly emerged in Beijing, we have tried to figure out the reasons for the outbreak since there were no COVID-19 cases found over the past two months," Wu Zunyou said.

"We came up with several possibilities, and the most likely one is that the carrier of the novel coronavirus comes from outside China or other parts of China and brought it here."

On Tuesday, another eight imported cases were reported.

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News Network
April 26,2020

Apr 26: The remarkable story of an airman who overcame prejudice to become one of only a handful of Indian fighter pilots in the First World War has emerged in newly-released archive files by the UK's Commonwealth War Graves Commission (CWGC).

Lieutenant Shri Krishna Chanda Welinkar is one of the thousands of moving stories from the war preserved in family correspondence and being brought alive as part of a digitisation project.

The never-before-published files contain thousands of letters, pictures and other papers sent between the Commission and the next of the kin of First World War dead.

Among them is the story of Welinkar, who hailed from Bombay in colonial India. After much hardship and discrimination, he eventually became a pilot and went missing while on patrol over the skies above the Western Front in June 1918.

His family had to wait nearly three years before they finally knew for certain that he had died, and his grave was located.

“For everyone who died in the First World War, there was inevitably a partner, parent or child back home who had questions. The heartbreaking letters in CWGC's archive give us an insight into what it was like for those families trying to come to terms with their loss,” said Andrew Fetherston, chief archivist for CWGC.

“They are stories that show desperate searches for closure, former enemies uniting and, on many occasions, the sad realisation that a missing loved one would always remain so. We are pleased to be able to make this invaluable piece of World War history accessible to a new generation and help deepen our understanding of how the First World War impacted those who were left behind,” he said.

Welinkar was one of the 1.3 million Indians who answered the call to fight for the British Empire. Nearly 74,000 never saw their homeland again and are remembered today in cemeteries and memorials throughout the world, including France, Belgium, the Middle East and Africa.

Welinkar was a well-educated man studying at Cambridge University. He trained to become an aviator in Middlesex and wished to join the Royal Flying Corps, later known as the Royal Air Force.

Upon attempting to enlist, Welinkar encountered the same prejudices as his other fellow Indian airmen and was encouraged to become an air mechanic instead.

He was eventually given a commission in the Royal Flying Corps as an Officer. In 1918, he was posted to France and patrolled the skies above the Western Front.

In June 1918, Lieutenant Welinkar embarked on what would be his final patrol; he did not return and was reported missing. His fate remained unknown for many months afterwards.

The newly-released e-files chronicle the remarkable discovery of Welinkar and his final resting place long after the war had ended. Colonel Barton, who knew Welinkar, acted on behalf of his mother and helped find her missing son. They spoke to former enemies and honed their search to the grave of an unidentified man, buried by the Germans as “Oberleutnant S.C. Wumkar” in a grave in Rouvroy, Belgium.

The body was later moved and reinterred in Hangard Communal Cemetery Extension but it wasn't until the vital clue, found in the original German burial records in February 1921, that it was confirmed beyond doubt this grave was of Welinkar's.

In May 1921, Colonel Barton, on behalf of Welinkar's mother, requested that a Commission headstone be placed on the grave with the following personal inscription: “To the Honoured Memory of One of the Empire's Bravest Sons”.

This records – known as Enquiry Files – are part of a collection of nearly 3,000 files which have never been made available to the public before. Nearly half have been digitised so far, alongside a previously unreleased collection of more than 16,000 photographs held in negatives in the Commission's archive.

The files, internally referred to simply as E-Files, contain correspondence between the CWGC and the next of kin of the war dead. They often contain letters, typed memos between Commission staff and on occasion photos, maps and diagrams.

CWGC only holds an enquiry file for a small proportion of the 1.7 million people it commemorates from the Commonwealth. Today it is only possible to release those surviving records from the First World War because correspondence with families of Second World War casualties often involves people still alive today and cannot be made public for many years, due to the UK's data protection rules.

To date, more than 1,300 of the surviving 3,000 First World War enquiry files have been digitised.

The CWGC commemorates the 1.7 million Commonwealth servicemen and women who died during the two World Wars. It also holds and updates an extensive and accessible records archive, while operating over 23,000 locations in more than 150 countries and territories.

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Agencies
April 17,2020

Washington, Apr 17: A record number of 4,591 Americans have died in the last 24 hours due to the deadly novel coronavirus in the US, which has the highest number of COVID-19 casualties in the world.

According to the Johns Hopkins University data, by 8 pm on Thursday, as many as 4,591 Americans have died in the last 24 hours, The Wall Street Journal said.

The previous highest was 2,569 on Wednesday.

By Thursday, more than 662,000 Americans tested positive with the coronavirus.

The dreaded disease, which originated in Wuhan city in China in December last year, has so far claimed more than 144,000 lives and infected over 2.1 million people.

The virus has infected over 671,000 people and claimed more than 33,000 lives, the highest for any country in the world.

New York City and its adjoining areas, including New Jersey and Connecticut have emerged as the epicenter of the virus in the US.

New York alone accounts for 226,000 cases of infections and 16,106 deaths.

In New Jersey, as many as 3,518 people have died of the disease and 75,317 have tested positive.

According to the US Centers for Disease Control and Prevention, till April 14, four per cent of the Americans infected with COVID-19 were of Asian origin and nearly one-third (30 per cent) were African Americans.

US President Donald Trump told reporters at the White House that experts and scientists report that his strategy to slow the spread of the virus has saved hundreds of thousands of lives.

Models predicted between 1.5 million and 2.2 million US deaths. If there was no mitigation, it could have even been higher than that and between 100,000 and 240,000 deaths with mitigation. It is looking like we will come far under even these lowest numbers, he said.

Noting that experts say the curve of the virus has flattened, and the peak in the new cases has passed, Trump said that nationwide, more than 850 counties or nearly 30 per cent of the country have reported no new cases in the last seven days.

Because of our early and aggressive action, we have avoided the tragedy of health care rationing and deadly shortfalls that have befallen in many other nations, nations which wherever possible we are helping, he said.

According to Trump, at least 35 clinical trials are already underway, including antiviral therapies, immune therapies, and blood therapies in the form of convalescent plasma. So far, more than 3.5 million tests have been carried out.

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