2838 Pakistanis, 914 Afghans, 172 Bangladeshis given Indian citizenship in last 6 years: Fin Min

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.

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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.

New Delhi, Mar 16: Reliance Group Chairman Anil Ambani has been summoned by the ED in connection with its money laundering probe against Yes Bank promoter Rana Kapoor and others, officials said on Monday.

They said Ambani was asked to depose at the Enforcement Directorate office in Mumbai on Monday as his group companies are among the big entities whose loans went bad after borrowing from the crisis-hit bank.

The officials said Ambani, 60, has sought exemption from appearance on some personal grounds and he may be issued a new date.

Ambani's group companies are stated to have taken loans of about Rs 12,800 crore from the bank that turned NPAs.

Finance Minister Nirmala Sitharaman had said in a March 6 press conference that the Anil Ambani Group, Essel, ILFS, DHFL and Vodafone were among the stressed corporates Yes Bank had exposure to.

Officials said promoters of all the big companies who had taken large loans from the beleaguered bank which later turned bad are being summoned for questioning in the case to take investigation forward.

Ambani's statement will be recorded under the Prevention of Money Laundering Act (PMLA) upon deposition, they said.

Kapoor, 62, is at present in ED custody after he was arrested by the central probe agency early this month.

The ED has accused Kapoor, his family members and others of laundering "proceeds of crime" worth Rs 4,300 crore by receiving alleged kickbacks in lieu of extending big loans through their bank that later turned NPA.

Mumbai, Jan 12: Thousands of citizens on Sunday congregated in Mumbai's suburban Jogeshwari to oppose the new citizenship law, the proposed NRC and NPR.

They also condemned last Sunday's violence on the JNU campus in Delhi, where masked men ran riot and attacked students. Leftist organisations had claimed RSS-affiliated ABVP's role in the attack, a charge denied by the students' body.

Former Tata Institute of Social Science (TISS) general secretary Fahad Ahmed told PTI that they assembled under the aegis of 'Hum Bharat Ke Log' in Millat Nagar area.

"Prime minister Narendra Modi should call 56 students from across the country to debate on the CAA, NRC and NPR," Ahmed said in an apparent jibe at Modi's "56 inch chest" remark, which the latter had made ahead of the 2014 Lok Sabha polls.

"Why the PM is not talking to us? Why is he not communicating? Even the Britishers used to talk to Indians whom they ruled, but our PM is not talking to poor people," he alleged.

Bollywood actor Sushasht Singh also spoke on the occasion.

"We are people of this country and such acts (CAA) are tarnishing the image of our country," he said.

At the gathering, people waved banners with slogans like "I Am From Gujarat, My Documents Burned in 2002", "No CAA, Boycott NRC, Stop Dividing India, Don't Divide us", "Save Constitution", written on them.

A large number of police personnel were present at the venue.

The Citizenship Amendment Act (CAA), which was notified on January 10, grants Indian citizenship to non-Muslim minorities migrated to India from Afghanistan, Pakistan and Bangladesh till December 31, 2014, following persecution over their faith.

Massive protests were witnessed against the CAA, mainly by the student community, since its passage by Parliament in December last year.

Opposition parties have been dubbing the CAA an "anti-Muslim" legislation, a charge being debunked by the government.

The Congress and other parties like the TMC have also opposed the proposed National Register of Citizens (NRC) and the National Population Register (NPR).

Union home minister Amit Shah has said that the government won't rest until persecuted refugees are granted Indian citizenship.