Congolese Denis Mukwege, Iraq's Nadia Murad win 2018 Nobel Peace Prize

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.

London, Jun 25: British Prime Minister Boris Johnson has called on India and China to engage in dialogue to sort out their border issues as he described the escalation in eastern Ladakh as "a very serious and worrying situation" which the UK is closely monitoring.

The first official statement of Mr Johnson came during his weekly Prime Minister's Questions (PMQs) in the House of Commons on Wednesday.

Responding to Conservative Party MP Flick Drummond on the implications for British interests of a dispute between a "Commonwealth member and the world's largest democracy on the one side, and a state that challenges our notion of democracy on the other," he described the escalation in eastern Ladakh as "a very serious and worrying situation", which the UK is "monitoring closely".

"Perhaps the best thing I can say... is that we are encouraging both parties to engage in dialogue on the issues on the border and sort it out between them," the Prime Minister said.

In a statement in New Delhi on Wednesday, the Ministry of External Affairs (MEA) said India and China have agreed that expeditious implementation of the previously agreed understanding on disengagement of troops from standoff points in eastern Ladakh would help ensure peace and tranquillity in the border areas.

During the diplomatic talks between India and China, the situation in the region was discussed in detail and the Indian side conveyed its concerns over the violent face-off in Galwan Valley on June 15. Twenty Indian Army personnel were killed in the clash. There were reports of several casualties for the Chinese army too, but China hasn't declared any official number yet.

The talks were held in the midst of escalating tension between the two countries following the violent clashes in Galwan Valley on June 15.

The Indian and Chinese armies are engaged in the standoff in Pangong Tso, Galwan Valley, Demchok and Daulat Beg Oldie in eastern Ladakh. A sizable number of Chinese Army personnel even transgressed into the Indian side of the Line of Actual Control in several areas including Pangong Tso.

United Nations, May 7: An average of 80,000 COVID-19 cases were reported each day in April to the World Health Organization, the top UN health agency has said, noting that South Asian nations like India and Bangladesh are seeing a spike in the infections while the numbers are declining in regions such as Western Europe.

WHO Director-General Tedros Adhanom Ghebreyesus said on Wednesday that countries must also be able to manage any risk of the disease being imported into their territories, and communities should be fully educated to adjust to what will be a "new norm".

He said as the countries press forward in the common fight against COVID-19, they should also lay the groundwork for resilient health systems globally.

"More than 3.5 million cases of COVID-19 and almost 250,000 deaths have now been reported to the WHO. Since the beginning of April, an average of around 80,000 new cases have been reported to the WHO every day," Ghebreyesus said in Geneva yesterday.

Asserting that the virus cases were not just numbers, he said: "every single case is a mother, a father, a son, a daughter, a brother, sister or friend".

He said while the numbers are declining in Western Europe, more cases are being reported every day from Eastern Europe, Africa, South-East Asia, the Eastern Mediterranean and the Americas. Even within regions and within countries, there are divergent trends, the agency added.

While some countries are reporting an increase in COVID-19 cases over time, many have seen caseloads rise because they have ramped up testing, the WHO official said.

"We've also seen in Europe and Western Europe a fundamental decrease in the number of cases, but we have seen an associated increase in the number of cases reported in places like the Russian Federation. Southeast, the Western Pacific areas are relatively on the downward trend like Korea and others, but then we do see in South Asia, in places like Bangladesh, in India, some trends towards increase.

"So it's very difficult to say that any particular region is improving or (not improving). There are individual countries within each region that are having difficulties getting on top of this disease and I am particularly concerned about those countries that have (an) ongoing humanitarian crisis," WHO's Executive Director Michael Ryan said.

The death toll due to COVID-19 in India rose to 1,783 while the number of cases climbed to 52,952 on Thursday, registering an increase of 89 deaths and 3,561 cases in the last 24 hours, the Union Health Ministry said.

The number of active COVID-19 cases stood at 35,902 while 15,266 people have recovered, it said.

Noting that while seeing an increase in the number of cases is not good in terms of transmission, WHO's Emerging Diseases and Zoonoses Unit head Maria Van Kerkhove said: "but I don't want to equate that with something (being) wrong".

"I want to equate that with countries are working very hard to increase their ability to find the virus, to find people with the virus, to have testing in place to identify who has COVID-19, and putting into place what they need to do to care for those patients," Kerkhove said.

With more countries considering easing restrictions implemented to curb the spread of the coronavirus, the WHO has again reminded the authorities of the need to maintain vigilance.

"The risk of returning to lockdown remains very real if countries do not manage the transition extremely carefully, and in a phased approach," Ghebreyesus said.

He urged countries to consider the UN agency's six criteria for lifting stay-at-home measures.

That advice includes ensuring surveillance is strong, cases are declining and transmission is controlled. Health systems also must be able to detect, isolate, test and treat cases, and to trace all contacts.

Additionally, the risk of outbreak in settings such as health facilities and nursing homes needs to be minimised, while schools, workplaces and other public locations should have preventive measures in place.

"The COVID-19 pandemic will eventually recede, but there can be no going back to business as usual. We cannot continue to rush to fund panic but let preparedness go by the wayside," he said.

He said the crisis has highlighted the importance of strong national health systems as the foundation of global health security: not only against pandemics but also against the multitude of health threats that people across the world face every day.

"If we learn anything from COVID-19, it must be that investing in health now will save lives later," Ghebreyesus said.

While the world currently spends around USD 7.5 trillion on health annually, the WHO believes the best investments are in promoting health and preventing disease.

"Prevention is not only better than cure, it's cheaper, and the smartest thing to do," he said.

The deadly coronavirus, which originated from the Chinese city of Wuhan in December last year, has infected over 3.7 million people and killed 263,831 people globally, according to a tally by Johns Hopkins University.