'Man-eating' tigress Avni, believed to be behind 13 deaths, killed finally

Paris, Apr 17: Even as virologists zero in on the virus that causes COVID-19, a very basic question remains unanswered: do those who recover from the disease have immunity?

There is no clear answer to this question, experts say, even if many have assumed that contracting the potentially deadly disease confers immunity, at least for a while.

"Being immunised means that you have developed an immune response against a virus such that you can repulse it," explained Eric Vivier, a professor of immunology in the public hospital system in Marseilles.

"Our immune systems remember, which normally prevents you from being infected by the same virus later on."

For some viral diseases such a measles, overcoming the sickness confers immunity for life.

But for RNA-based viruses such as Sars-Cov-2 -- the scientific name for the bug that causes the COVID-19 disease -- it takes about three weeks to build up a sufficient quantity of antibodies, and even then they may provide protection for only a few months, Vivier told AFP.

At least that is the theory. In reality, the new coronavirus has thrown up one surprise after another, to the point where virologists and epidemiologists are sure of very little.

"We do not have the answers to that -- it's an unknown," Michael Ryan, executive director of the World Health Organization's Emergencies Programme said in a press conference this week when asked how long a recovered COVID-19 patient would have immunity.

"We would expect that to be a reasonable period of protection, but it is very difficult to say with a new virus -- we can only extrapolate from other coronaviruses, and even that data is quite limited."

For SARS, which killed about 800 people across the world in 2002 and 2003, recovered patients remained protected "for about three years, on average," Francois Balloux director of the Genetics Institute at University College London, said.

"One can certainly get reinfected, but after how much time? We'll only know retroactively."

A recent study from China that has not gone through peer review reported on rhesus monkeys that recovered from Sars-Cov-2 and did not get reinfected when exposed once again to the virus.

"But that doesn't really reveal anything," said Pasteur Institute researcher Frederic Tangy, noting that the experiment unfolded over only a month.

Indeed,several cases from South Korea -- one of the first countries hit by the new coronavirus -- found that patients who recovered from COVID-19 later tested positive for the virus.

But there are several ways to explain that outcome, scientists cautioned.

While it is not impossible that these individuals became infected a second time, there is little evidence this is what happened.

More likely, said Balloux, is that the virus never completely disappeared in the first place and remains -- dormant and asymptomatic -- as a "chronic infection", like herpes.

As tests for live virus and antibodies have not yet been perfected, it is also possible that these patients at some point tested "false negative" when in fact they had not rid themselves of the pathogen.

"That suggests that people remain infected for a long time -- several weeks," Balloux added. "That is not ideal."

Another pre-publication study that looked at 175 recovered patients in Shanghai showed different concentrations of protective antibodies 10 to 15 days after the onset of symptoms.

"But whether that antibody response actually means immunity is a separate question," commented Maria Van Kerhove, Technical Lead of the WHO Emergencies Programme.

"That's something we really need to better understand -- what does that antibody response look like in terms of immunity."

Indeed, a host of questions remain.

"We are at the stage of asking whether someone who has overcome COVID-19 is really that protected," said Jean-Francois Delfraissy, president of France's official science advisory board.

For Tangy, an even grimmer reality cannot be excluded.

"It is possible that the antibodies that someone develops against the virus could actually increase the risk of the disease becoming worse," he said, noting that the most serious symptoms come later, after the patient had formed antibodies.

For the moment, it is also unclear whose antibodies are more potent in beating back the disease: someone who nearly died, or someone with only light symptoms or even no symptoms at all. And does age make a difference?

Faced with all these uncertainties, some experts have doubts about the wisdom of persuing a "herd immunity" strategy such that the virus -- unable to find new victims -- peters out by itself when a majority of the population is immune.

"The only real solution for now is a vaccine," Archie Clements, a professor at Curtin University in Perth Australia, told AFP.

At the same time, laboratories are developing a slew of antibody tests to see what proportion of the population in different countries and regions have been contaminated.

Such an approach has been favoured in Britain and Finland, while in Germany some experts have floated the idea of an "immunity passport" that would allow people to go back to work.

"It's too premature at this point," said Saad Omer, a professor of infectious diseases at the Yale School of Medicine.

"We should be able to get clearer data very quickly -- in a couple of months -- when there will be reliable antibody tests with sensitivity and specificity."

One concern is "false positives" caused by the tests detecting antibodies unrelated to COVID-19.

The idea of immunity passports or certificates also raises ethical questions, researchers say.

"People who absolutely need to work -- to feed their families, for example -- could try to get infected," Balloux.

New Delhi, Jan 17: E-commerce major Amazon on Friday said it plans to create one million new jobs in India over the next five years through investments in technology, infrastructure and its logistics network.

These jobs are in addition to the seven lakh jobs Amazon's investments have enabled over the last six years in the country.

"Amazon plans to create one million new jobs in India by 2025," the company said in a statement, adding that the jobs - created both directly and indirectly - will be across industries, including information technology, skill development, content creation, retail, logistics, and manufacturing.

Amazon.com Inc chief Jeff Bezos had on Wednesday announced USD 1 billion (over Rs 7,000 crore) investment in India to help bring small and medium businesses online and committed to exporting USD 10 billion worth of India-made goods by 2025.

"We are investing to create a million new jobs here in India over the next five years," Bezos said.

"We’ve seen huge contributions from our employees, extraordinary creativity from the small businesses we've partnered with, and great enthusiasm from the customers who shop with us—and we’re excited about what lies ahead," Bezos added.

India has prioritised job creation and skilling initiatives – including the training of more than 400 million people by 2022 – in rural and urban areas.

"Amazon’s job creation commitment and investment in traders and micro, small and medium enterprises (MSMEs) complement this social inclusion and social mobility efforts by creating more opportunities for people in India to find employment, build skills, and expand entrepreneurship opportunities," the statement said.

The new investments will help to hire talent to fill roles across Amazon in India, including software development engineering, cloud computing, content creation, and customer support.

Since 2014, Amazon has grown its employee base more than four times, and last year inaugurated its new campus building in Hyderabad – Amazon’s first fully-owned campus outside the United States and the largest building globally in terms of employees (15,000) and space (9.5 acres).

The investments will also help in expanding growth opportunities for the more than 5,50,000 traders and micro, small, and medium-sized businesses – including local shops – through programs like Saheli, Karigar, and “I Have Space”.

Rome, Mar 11: Italy has recorded its deadliest day of the coronavirus crisis despite locking down the entire country, as New York deployed the National Guard to contain a disease that has sown worldwide panic.

The hardest-hit country in Europe said its death toll from the COVID-19 virus had risen Tuesday by a third to 631, with the surging epidemic taking its toll on global sporting, cultural and political events.

While authorities in China, where the outbreak began, have declared it "basically curbed", cases are multiplying around the world, sparking panic buying in shops, and wild swings on financial markets.

China remains the hardest-hit overall with more than 80,000 cases and over 3,000 deaths, out of a global total of 117,339 cases and 4,251 deaths across 107 countries and territories, according to an AFP tally.

The virus is infecting all walks of life, including politics, with US Democratic presidential hopefuls Bernie Sanders and Joe Biden both cancelling campaign rallies and British health minister Nadine Dorries saying she had tested positive.

And amid criticism of the US authorities' response, New York deployed the National Guard for the first time during the crisis to help contain the spread of the disease from an infection-hit suburb.

There have been 173 confirmed cases in New York state, including 108 in Westchester County, home to New Rochelle where the majority of infections have been detected.

"It is a dramatic action, but it is the largest cluster in the country. This is literally a matter of life and death," said state governor Andrew Cuomo.

"People are scared, it's an unusual situation to be in," Miles Goldberg, who runs a New Rochelle bar, told AFP.

"It makes people nervous to be around others, it makes people nervous to get inside into businesses and such," he said.

In an unprecedented move, Italian Prime Minister Giuseppe Conte has told the 60 million residents of his country they should travel only for the most urgent work or health reasons.

And while squares in Milan and Rome were emptied of their usual bustle and traffic, some residents appeared uncertain if they were even allowed to leave their homes for everyday tasks like shopping.

The virus has battered tourism around the world, as people scrap travel plans, and a restaurant owner in Florence in northern Italy said that the impact on business had been catastrophic.

"We hope that we will see the end of it, because from around 140 covers a day, this afternoon, we've gone down to 20-25," Agostino Ferrara told AFP.

Pope Francis also seemed to muddy the waters, holding a mass in which he urged priests to go out and visit the sick -- something Conte has specifically discouraged.

Sporting events continued to fall victim to the virus as authorities urge people to avoid large gatherings.

Arsenal's game at Manchester City was postponed after players from the London club were put into quarantine, making it the first Premier League fixture to be called off because of the virus.

The virus has sparked doubts about the Olympics due to open in Tokyo on July 24 and the traditional flame lighting ceremony in Greece is set to be held without spectators.

In the United States, organisers rescheduled the two-week Coachella music festival for October.

The virus and the response to the crisis has prompted pandemonium on global markets with volatility not seen since the world financial crisis in 2008.

After suffering its worst session in more than 11 years at the beginning of the week, the Dow Jones Index in New York bounced back significantly, rising five percent on Tuesday.

Politicians around the world have scrambled to put together emergency packages to ease the significant financial hardships the virus is expected to cause for households and businesses.

US President Donald Trump, who is relying on a strong economy to boost his re-election hopes, promised to announce "major" economic measures on Tuesday.

The biggest item on his wish list is a cut in payroll taxes. But even allies in Congress and reportedly some aides in the White House are sceptical, questioning the cost.

Italy prepared Tuesday to let families skip mortgage and some tax payments while Japan unveiled a second emergency package to tackle economic woes stemming from the outbreak, including $15 billion in loan programmes to support small businesses.

Analysts warned of further volatility ahead however.

"It's like winding up a rubber band. The more you wind it, when you let go, the more it pops," said LBBW's Karl Haeling.

"A lot of the uncertainty goes to the root of the virus itself."