At least 10 dead, several injured in Lahore blast

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.

Jan 28: China said on Tuesday that 106 people had died from a new coronavirus that is spreading across the country, up from the previous toll of 81.

The number of total confirmed cases in China rose to 4,515 as of Jan. 27, the National Health Commission said in a statement, up from 2,835 reported a day earlier.

The United States warned against travel to China on Monday and Canada issued a more narrow travel warning as the death toll from the spreading coronavirus passed 100, with tens of millions stranded during the biggest holiday of the year and global markets rattled.

Global stocks fell, oil prices hit three-month lows, and China's yuan dipped to its weakest level in 2020 as investors fretted about damage to the world's second-biggest economy from travel bans and the Lunar New Year holiday, which China extended in a bid to keep people at home.

The health commission of China's Hubei province said on Tuesday that 100 people had died from the virus as of Jan. 27, according to an online statement, up from the previous toll of 76, with the number of confirmed cases in the province rose to 2,714.

Other fatalities have been reported elsewhere in China, including the first in Beijing, bringing the deal toll to 106 so far, according to the People's Daily. The state newspaper put the total number of confirmed cases in China at 4,193, though some experts suspect a much higher number.

On Monday, US President Donald Trump offered China whatever help it needed, while the State Department said Americans should "reconsider" visiting all of China due to the virus.

Canada, which has two confirmed cases of the virus and is investigating 19 more potential cases, warned its citizens to avoid travel to China's Hubei province, at the heart of the outbreak.

Authorities in Hubei province are taking increasing flak from the public over their initial response to the virus. Chinese Premier Li Keqiang visited the city of Wuhan, epicentre of the outbreak, to encourage medical workers and promise reinforcements.

Visiting Wuhan in blue protective suit and mask, Li praised medics, said 2,500 more workers would join them in the next two days, and visited the site of a new hospital to be built in days.

The most senior leader to visit Wuhan since the outbreak, Li was shown on state TV leading medical workers in chants of "Wuhan jiayou!" - an exhortation to keep their strength up.

China's ambassador to the United Nations, following a meeting with UN Secretary-General António Guterres on Monday, said "the Chinese government attaches paramount importance to prevention and control of the epidemic, and President Xi Jinping has given important instructions. ...

"China has been working with the international community in the spirit of openness, transparency and scientific coordination," he said.

Guterres said in a statement, "The UN appreciates China's effort, has full confidence in China's ability of controlling the outbreak, and stands ready to provide any support and assistance."

MOUNTING ANGER

On China's heavily censored social media, officials have faced mounting anger over the virus, which is thought to have originated from a market where wildlife was sold illegally.

Some criticised the governor of Hubei province, of which Wuhan is the capital, after he corrected himself twice during a news conference over the number of face masks being produced.

"If he can mess up the data multiple times, no wonder the disease has spread so severely," said one user of the Weibo social media platform.

In rare public self-criticism, Wuhan Mayor Zhou Xianwang said the city's management of the crisis was "not good enough" and indicated he was willing to resign.

The central Chinese city of 11 million people is in virtual lockdown and much of Hubei, home to nearly 60 million people, is under travel curbs.

Elsewhere in China, people from the region faced questioning about their movements. "Hubei people are getting discriminated against," a Wuhan resident complained on Weibo.

Cases linked to people who travelled from Wuhan have been confirmed in a dozen countries, from Japan to the United States, where authorities said they had 110 people under investigation in 26 states. Sri Lanka was the latest to confirm a case.

INVESTORS WORRIED

Investors are worried about the impact. The consensus is that in the short term, economic output will be hit as authorities limit travel and extend the week-long New Year holiday — when millions traditionally travel by rail, road and plane - by three days to limit spread of the virus.

Asian and European shares tumbled, with Japan's Nikkei average sliding 2%, its biggest one-day fall in five months. Demand spiked for safe-haven assets such as the Japanese yen and Treasury notes. European stocks fell more than 2%.

The US S&P 500 closed down nearly 1.6%.

"China is the biggest driver of global growth so this couldn't have started in a worse place," said Alec Young, FTSE Russell's managing director of global markets research.

During the 2002-2003 outbreak of Severe Acute Respiratory Syndrome (SARS), which originated in China and killed nearly 800 people globally, air passenger demand in Asia plunged 45%. The travel industry is more reliant on Chinese travellers now.

Chinese-ruled Hong Kong, which has had eight cases, banned entry to people who had visited Hubei recently.

Some European tour operators cancelled trips to China, while governments around the world worked on repatriating nationals.

Officially known as 2019-nCoV, the newly identified coronavirus can cause pneumonia, but it is still too early to know just how dangerous it is and how easily it spreads.

"What we know about this virus it that transmission occurs through human contact but we are speaking of close contact, i.e. less than a meter," said Jerome Salomon, a senior official with France's health ministry.

"Crossing someone (infected) in the street poses no threat," he said. "The risk is low when you spend a little time near that person and becomes higher when you spend a lot of time near that person."

Stockholm, Jun 15: Nuclear powers continue to modernise their arsenals, researchers said Monday, warning that tensions were rising and the outlook for arms control was "bleak".

"The loss of key channels of communication between Russia and the USA... could potentially lead to a new nuclear arms race," said Shannon Kile, director of the nuclear arms control programme at the Stockholm International Peace Research Institute (SIPRI) and co-author of the report.

Russia and the US account for more than 90 percent of the world's nuclear weapons.

Kile was referring to the future of the New START treaty between the US and Russia, which is set to expire in February 2021.

It is the final nuclear deal still in force between the two superpowers, aimed at maintaining their nuclear arsenals below Cold War levels.

"Discussions to extend New START or to negotiate a new treaty made no progress in 2019," the SIPRI researchers noted.

At the same time, nuclear powers continue to modernise their weapons while China and India are increasing the size of their arsenals.

"China is in the middle of a significant modernisation of its nuclear arsenal. It is developing a so-called nuclear triad for the first time, made up of new land- and sea-based missiles and nuclear-capable aircraft," SIPRI said.

The country has repeatedly rejected Washington's insistence that it join any future nuclear arms reduction talks.

The number of nuclear warheads declined in the past year.

At the start of 2020, the United States, Russia, Britain, China, India, Pakistan, Israel and North Korea together had 13,400 nuclear arms, according to SIPRI's estimates, 465 fewer than at the start of 2019.

The decline was attributed mainly to the United States and Russia.

While the future of the New START treaty remains uncertain, Washington and Moscow have continued to respect their obligations under the accord.

"In 2019, the forces of both countries remained below the limits specified by the treaty," the report said. But both nations "have extensive and expensive programmes underway to replace and modernise their nuclear warheads, missile and aircraft delivery systems, and nuclear weapon production facilities," it added.

"Both countries have also given new or expanded roles to nuclear weapons in their military plans and doctrines, which marks a significant reversal of the post-Cold War trend towards the gradual marginalisation of nuclear weapons."

The Treaty on the Non-Proliferation of Nuclear Weapons (NPT), a cornerstone of the global nuclear non-proliferation regime, celebrates its 50th anniversary this year.

The number of nuclear arms worldwide has declined since hitting a peak of almost 70,000 in the mid-1980s.

The five original nuclear powers -- Washington, Beijing, Moscow, Paris and London -- in March reiterated their commitment to the treaty.