Fidel Castro, who defied 10 US presidents in his 50 year rule, dies aged 90

May 15: Global tensions simmered over the race for a coronavirus vaccine Thursday, as the United States and China traded jabs, and France slammed pharmaceuticals giant Sanofi for suggesting the US would get any eventual vaccine first.

Scientists are working at breakneck speed to develop a vaccine for COVID-19, the disease caused by the virus, which has killed more than 300,000 people worldwide and pummelled economies.

From the US to Europe to Asia, national and local governments are easing lockdown orders to get people back to work -- while fretting over a possible second wave of infections.

Increased freedom of movement means an increased risk of contracting the virus, and so national labs and private firms are labouring to find the right formula for a vaccine.

The European Union's medicines agency offered some hope when it said one could be ready in a year, based on data from clinical trials already underway.

But Marco Cavaleri, the EMA's head of vaccines strategy, acknowledged that timeline was a "best-case scenario," and cautioned that "there may be delays."

The race for a vaccine has exposed a raw nerve in relations between the United States and China, where the virus was first detected late last year in the central city of Wuhan.

Two US agencies warned Wednesday that Chinese hackers were trying to steal COVID-19 vaccine research -- a claim Beijing rejected as "smearing" its reputation.

US President Donald Trump, who has ratcheted up the rhetoric against China, said he doesn't even want to engage with Chinese leader Xi Jinping -- potentially imperilling a trade deal between the world's top two economies.

"I'm very disappointed in China. I will tell you that right now," he said in an interview with Fox Business.

"There are many things we could do. We could do things. We could cut off the whole relationship."

On Capitol Hill, an ousted US health official told Congress that the Trump government had no strategy in place to find and distribute a vaccine to millions of Americans, warning of the "darkest winter" ahead.

"We don't have a single point of leadership right now for this response, and we don't have a master plan," said Rick Bright, who was removed last month as head of the US agency charged with developing a coronavirus vaccine.

The United States has registered nearly 86,000 deaths linked to COVID-19 -- the highest toll of any nation.

World leaders were among 140 signatories to a letter published Thursday saying any vaccine should not be patented and that the science should be shared among nations.

"Governments and international partners must unite around a global guarantee which ensures that, when a safe and effective vaccine is developed, it is produced rapidly at scale and made available for all people, in all countries, free of charge," it said.

But a row erupted in France after drugmaker Sanofi said it would reserve first shipments of any vaccine it discovered to the United States.

The comments prompted a swift rebuke from the French government -- President Emmanuel Macron's office said any vaccine should be treated as "a global public good, which is not submitted to market forces."

Sanofi chief executive Paul Hudson said the US had a risk-sharing model that allowed for manufacturing to start before a vaccine had been finally approved -- while Europe did not.

"The US government has the right to the largest pre-order because it's invested in taking the risk," Hudson told Bloomberg News.

Macron's top officials are scheduled to meet with Sanofi executives about the issue next week.

The search for a vaccine became even more urgent after the World Health Organization said the disease may never go away and the world would have to learn to live with it for good.

"This virus may become just another endemic virus in our communities and this virus may never go away," said Michael Ryan, the UN body's emergencies director.

The prospect of the disease lingering leaves governments facing a delicate balancing act between suppressing the pathogen and getting their economies up and running.

In the US, more grim economic data emerged Thursday, with nearly three million more Americans applying for unemployment benefits.

That takes the overall total to 36.5 million -- more than 10 percent of the US population.

Further signs of the damage to businesses emerged when Lloyd's of London forecast the pandemic will cost the global insurance industry about $203 billion.

European markets closed down, but Wall Street rallied despite the new jobless claims. In a sign of progress, the New York Stock Exchange trading floor was due to reopen on May 26.

The reopening of economies continued in earnest across Europe, where the EU has set out proposals for a phased restart of travel and the eventual lifting of border controls.

"Maybe it's a mistake, but we have no choice. Without tourists, we won't get by!" Enrico Facchetti, a 61-year-old former goldsmith, said of Venice's reopening.

Japan -- the world's third largest economy -- lifted a state of emergency across most of the country except for Tokyo and Osaka.

And Canadian Prime Minister Justin Trudeau said national parks would partially reopen on June 1.

But in Latin America, the virus continued to surge, with a 60 percent leap in cases in the Chilean capital of Santiago.

Authorities said 2,000 new graves were being dug at the main cemetery.

South Sudan reported its first COVID-19 death on Thursday.

And in Bangladesh, the first case was confirmed in the teeming Rohingya refugee camps in Bangladesh, which are home to nearly one million people.

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.

Feb 11: China reported 108 new coronavirus deaths on February 10, the highest daily toll since the outbreak began in Wuhan late last year, as two senior officials in the hard-hit province of Hubei were removed from their jobs.

The total number of deaths on the mainland reached 1,016 in the 24 hours until midnight, the National Health Commission said on Tuesday.

Some 2,478 new cases were confirmed, bringing the total to 42,638.

Of the new deaths, 103 were in the province of Hubei, including 67 in the provincial capital of Wuhan. The virus is thought to have originated there in a market that sold seafood as well as wild animals.

Two senior health officials in the province - Zhang Jin who was Party Secretary of the health commission for Hubei and Ling Yingzi who was director of the Hubei Provincial Health Commission - were both removed from their posts, state media reported on Tuesday,  a day after Chinese President Xi Jinping visited health facilities in Beijing.

In his first public appearance since the outbreak began, Xi donned a face mask and had his temperature checked while visiting medical workers and patients in the capital.

"We have seen very little of Xi Jinping since the outbreak began but he was out and about in Beijing on Monday," Al Jazeera's Katrina Yu said from Beijing. "He has been trying to rally the troops saying: 'We can win this battle.' But it's also a sign that the battle is far from over."

The other fatalities on Monday were in the provinces of Heilongjiang, Anhui and Henan and the cities of Tianjin and Beijing, the National Health Commission said.

During a meeting chaired by Premier Li Keqiang on Monday, a group of leaders tasked with beating the virus said it would work to solve raw material and labour shortages and boost supplies of masks and protective clothing.

They said nearly 20,000 medical personnel from around the country had already been sent to Wuhan, and more medical teams were also on the way.