Khaleda Zia granted 4-month bail in 2008 corruption case

The coronavirus can stay aloft for hours in tiny droplets in stagnant air, infecting people as they inhale, mounting scientific evidence suggests.

This risk is highest in crowded indoor spaces with poor ventilation, and may help explain superspreading events reported in meatpacking plants, churches and restaurants.

It’s unclear how often the virus is spread via these tiny droplets, or aerosols, compared with larger droplets that are expelled when a sick person coughs or sneezes, or transmitted through contact with contaminated surfaces, said Linsey Marr, an aerosol expert at Virginia Tech.

Follow latest updates on the Covid-19 pandemic here

Aerosols are released even when a person without symptoms exhales, talks or sings, according to Marr and more than 200 other experts, who have outlined the evidence in an open letter to the World Health Organization.

What is clear, they said, is that people should consider minimizing time indoors with people outside their families. Schools, nursing homes and businesses should consider adding powerful new air filters and ultraviolet lights that can kill airborne viruses.

What does it mean for a virus to be airborne?

For a virus to be airborne means that it can be carried through the air in a viable form. For most pathogens, this is a yes-no scenario. HIV, too delicate to survive outside the body, is not airborne. Measles is airborne, and dangerously so: It can survive in the air for up to two hours.

For the coronavirus, the definition has been more complicated. Experts agree that the virus does not travel long distances or remain viable outdoors. But evidence suggests it can traverse the length of a room and, in one set of experimental conditions, remain viable for perhaps three hours.

How are aerosols different from droplets?

Aerosols are droplets, droplets are aerosols — they do not differ except in size. Scientists sometimes refer to droplets fewer than 5 microns in diameter as aerosols. (By comparison, a red blood cell is about 5 microns in diameter; a human hair is about 50 microns wide.)

From the start of the pandemic, the WHO and other public health organizations have focused on the virus’s ability to spread through large droplets that are expelled when a symptomatic person coughs or sneezes.

These droplets are heavy, relatively speaking, and fall quickly to the floor or onto a surface that others might touch. This is why public health agencies have recommended maintaining a distance of at least 6 feet from others, and frequent hand washing.

But some experts have said for months that infected people also are releasing aerosols when they cough and sneeze. More important, they expel aerosols even when they breathe, talk or sing, especially with some exertion.

Scientists know now that people can spread the virus even in the absence of symptoms — without coughing or sneezing — and aerosols might explain that phenomenon.

Because aerosols are smaller, they contain much less virus than droplets do. But because they are lighter, they can linger in the air for hours, especially in the absence of fresh air. In a crowded indoor space, a single infected person can release enough aerosolized virus over time to infect many people, perhaps seeding a superspreader event.

For droplets to be responsible for that kind of spread, a single person would have to be within a few feet of all the other people, or to have contaminated an object that everyone else touched. All that seems unlikely to many experts: “I have to do too many mental gymnastics to explain those other routes of transmission compared to aerosol transmission, which is much simpler,” Marr said.

Can I stop worrying about physical distancing and washing my hands?

Physical distancing is still very important. The closer you are to an infected person, the more aerosols and droplets you may be exposed to. Washing your hands often is still a good idea.

What’s new is that those two things may not be enough. “We should be placing as much emphasis on masks and ventilation as we do with hand washing,” Marr said. “As far as we can tell, this is equally important, if not more important.”

Should I begin wearing a hospital-grade mask indoors? And how long is too long to stay indoors?

Health care workers may all need to wear N95 masks, which filter out most aerosols. At the moment, they are advised to do so only when engaged in certain medical procedures that are thought to produce aerosols.

For the rest of us, cloth face masks will still greatly reduce risk, as long as most people wear them. At home, when you’re with your own family or with roommates you know to be careful, masks are still not necessary. But it is a good idea to wear them in other indoor spaces, experts said.

As for how long is safe, that is frustratingly tough to answer. A lot depends on whether the room is too crowded to allow for a safe distance from others and whether there is fresh air circulating through the room.

What does airborne transmission mean for reopening schools and colleges?

This is a matter of intense debate. Many schools are poorly ventilated and are too poorly funded to invest in new filtration systems. “There is a huge vulnerability to infection transmission via aerosols in schools,” said Don Milton, an aerosol expert at the University of Maryland.

Most children younger than 12 seem to have only mild symptoms, if any, so elementary schools may get by. “So far, we don’t have evidence that elementary schools will be a problem, but the upper grades, I think, would be more likely to be a problem,” Milton said.

College dorms and classrooms are also cause for concern.

Milton said the government should think of long-term solutions for these problems. Having public schools closed “clogs up the whole economy, and it’s a major vulnerability,” he said.

“Until we understand how this is part of our national defense, and fund it appropriately, we’re going to remain extremely vulnerable to these kinds of biological threats.”

What are some things I can do to minimize the risks?

Do as much as you can outdoors. Despite the many photos of people at beaches, even a somewhat crowded beach, especially on a breezy day, is likely to be safer than a pub or an indoor restaurant with recycled air.

But even outdoors, wear a mask if you are likely to be close to others for an extended period.

When indoors, one simple thing people can do is to “open their windows and doors whenever possible,” Marr said. You can also upgrade the filters in your home air-conditioning systems, or adjust the settings to use more outdoor air rather than recirculated air.

Public buildings and businesses may want to invest in air purifiers and ultraviolet lights that can kill the virus. Despite their reputation, elevators may not be a big risk, Milton said, compared with public bathrooms or offices with stagnant air where you may spend a long time.

If none of those things are possible, try to minimize the time you spend in an indoor space, especially without a mask. The longer you spend inside, the greater the dose of virus you might inhale.

London: Italy on Friday recorded the most daily deaths of any country since the start of the coronavirus pandemic and Spain had its deadliest day, as British Prime Minister Boris Johnson became the first major world leader to test positive.

Italy reported 969 new deaths, Spain 769 and France 299 as Europe reeled from a crisis that has put millions at risk around the world and threatened a global economic meltdown.

In other grim milestones, AFP tallies showed a total of 300,000 cases now recorded in Europe with more than 26,000 deaths worldwide, and the United States overtook China as the country with the most infections.

Italy showed infection rates continuing a downward trend and Spain said its rate of new infections appeared to be slowing, but other countries were bracing to feel the full impact of the virus's spread.

The World Health Organization's regional director for Africa warned the continent faced a "dramatic evolution" of the pandemic, as South Africa became the latest nation to start life under lockdown and reported its first COVID-19 deaths.

Johnson, whose country has seen more than 14,000 declared coronavirus cases and 759 deaths, said he had developed mild symptoms over the previous 24 hours and was self-isolating after testing positive.

Britain's Health Secretary Matt Hancock also tested positive with mild symptoms.

Europe has suffered the brunt of the coronavirus crisis in recent weeks, with millions across the continent on lockdown and the streets of Paris, Rome and Madrid eerily empty.

In France — where nearly 2,000 people have died -- the government announced it was extending its stay-at-home order until at least April 15. While severe, the 299 new deaths it recorded on Friday was lower than the 365 reported the previous day.

The death of a 16-year-old girl from the virus has particularly shaken France, and shattered the belief of many young people that they are immune.

The girl's mother Sabine told AFP that Julie "just had a cough" at first but deteriorated quickly. She died on Wednesday, less than a week after showing her first symptoms.

"It's unbearable," Sabine said. "We were supposed to have a normal life."

Focus was also turning to the United States, where the number of known infections jumped by 18,000 on Friday, reaching more than 97,000 -- higher than both China and Italy. The US also recorded 345 deaths over the past 24 hours, with a total toll of 1,478.

In New York City, health workers are battling a surging toll of dead and infected at the US epicentre of the crisis, including an increasing number of younger patients.

"Now it's 50-year-olds, 40-year-olds, 30-year-olds," said one respiratory therapist at the Jewish Medical Center in Queens.

They "didn't listen about not going out or protecting themselves and washing their hands", he said.

- 'Afraid and lost' -

The coronavirus first emerged in China late last year before spreading globally, with more than half a million declared cases in 183 countries and territories.

Over the last six days, as many new cases have been diagnosed around the world as in the previous 80 days.

Beijing managed to contain its spread with lockdowns and quarantines and its epicentre Wuhan is in the process of easing severe movement restrictions in place for two months.

Three billion people around the world have been told to stay indoors.

In a historic first, Pope Francis performed the rarely recited "Urbi et Orbi" blessing to an empty Saint Peter's Square.

"Thick darkness has gathered over our squares, our streets and our cities; it has taken over our lives, filling everything with a deafening silence and a distressing void, that stops everything as it passes by," he said.

"We find ourselves afraid and lost," he said, describing the coronavirus as a "tempest".

Health care systems even in the most developed nations are stretched to breaking point and medical workers have been having to make difficult choices.

"If I've got five patients and only one bed, I have to choose who gets it," Sara Chinchilla, a paediatrician at a hospital near Madrid, told AFP.

The WHO's chief Tedros Adhanom Ghebreyesus said the dire lack of protective gear for frontline health workers was one of the most pressing problems in the fight to prevent deaths.

"The chronic global shortage of personal protective equipment is now one of the most urgent threats to our collective ability to save lives," he told a virtual news conference in Geneva.

Lockdowns and other measures are wreaking havoc on the global economy, with fears of a downturn worse than the Great Depression of the 1930s.

"It is clear that we have entered a recession" that will be worse than in 2009 following the global financial crisis, International Monetary Fund chief Kristalina Georgieva said Friday.

Unprecedented stimulus measures have helped markets bounce back after a brutal month, but people around the world are bracing for economic hardship.

The United States reported that 3.3 million people applied for unemployment benefits last week -- by far the highest number ever recorded.

Retail workers in particular have suffered as many countries shutter non-essential business, while airlines and the global tourism industry have been dealt devastating blows.

The fashion industry was the latest hit on Friday, with Paris men's fashion week and haute couture shows cancelled along with Milan men's fashion week.

- Armies of volunteers -

The World Tourism Organization said Friday it expected tourist arrivals to fall by 20-30 percent this year, with losses of $300 billion-450 billion in international tourism receipts.

But there have been rays of hope in the midst of the crisis.

Armed groups in Cameroon, the Philippines and Yemen have moved in recent days to reduce violence after UN Secretary General Antonio Guterres issued an appeal for ceasefires.

And armies of volunteers have emerged in many countries to bring help to the needy, with food deliveries for the elderly, free taxi rides, accommodation for health workers, and even home-sewn face masks.

Dubai/Abu Dhabi, May 7: A group passengers who are scheduled to fly to Kozhikode on the first COVID-19 Indian repatriation flight have begun streaming in to Terminal 2 at Dubai International Airport.

Wearing masks and gloves, the passengers are now waiting for the medical screening and check-in services to begin.

Airport officials gave entry to the departure terminal only to passengers with tickets.

Naif resident Mahamood P.P, 60, was among the first to reach as he was not informed about the change in the flight schedule, he told Gulf News.

“I reached here at 9.30am as I didn’t get any information about the 2.10pm flight getting rescheduled to the evening,” he said.

Suffering from a heart disease, Mahmood, who works as a juice maker at a juice shop near Naif Police station, said he stepped out of his room for the first time in two months.

“As there were many cases in Naif, I never went out because of my health condition. Since I was not in contact with anyone else other than my roommates who also never went out, I didn’t go for the COVID screening also. I was worried that I might be exposed to infection while waiting for the tests,” he said.

He thanked the Indian Consulate for giving him priority to fly home. “I need to go for my heart checkup. So I wanted to fly home as soon as possible.”

However, he said his son, a civil engineer who came here searching for a job, is not flying back though he is on a visit visa.

“Since the UAE government has allowed people on visit visa to stay here till December, he has decided to try his luck in getting a job,” said Mahamood.

Sneha Thomas, who is eight months pregnant, was also among the first to arrive at the airport.

Her husband Somi Jose came to drop her.

Thomas is among 11 pregnant women flying on the Dubai-Kozhikode flight.

Sharjah resident for 30 years, Mohammed Ali Yaseen, who is also the secretary of the Kerala Muslim Cultural Centre in Sharjah, said he is flying home as the restaurant he was running had to be closed due to a demolition plan of the building.

“Three months ago I got the notice to vacate the building and I had to close the restaurant. I was looking for another shop. But then the coronavirus hit. Now there is no point in me opening me a new shop as those who are already operational are not getting any business.”

He said he decided to drop the plan and go home for now. “My visa and license are still valid. I will try to come back when this pandemic ends and things are better.”

Meanwhile, at the Au Dhabi International Airport, families with kids were given priority to proceed towrards check-in. at terminal 3. The passengers coming in right now were mostly women who were on a visit visa. Pregnant women and the elderly too were given priority.