Coronavirus airborne: What we should do now

International New York Times
July 7, 2020

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.

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News Network
July 2,2020

Jul 2: Democratic presidential candidate and former US vice-president Joe Biden has said that if he wins the November elections, strengthening the relationship with India which is America’s "natural partner", will be a high priority for his administration.

"India needs to be a partner in the region for our safety's sake and quite frankly for theirs," he said in response to a question on India-US relationship during a virtual fundraiser event on Wednesday.

At the fundraiser hosted by Chairman and CEO of Beacon Capital Partners Alan Leventhal, the former vice president said that India and the United States were natural partners.

"That partnership, a strategic partnership, is necessary and important in our security," Biden said when asked by an attendee whether India is critical to the US' national security.

Referring to his eight years as the vice president, he said, "In our administration, I was proud to play a role more than a decade ago in securing Congressional approval for the US-India Civil Nuclear Agreement, which is a big deal".

"Helping open the door to great progress in our relationship and strengthening our strategic partnership with India was a high priority in the Obama-Biden administration and will be a high priority if I'm elected president,” Biden said.

Both as the vice president and a senator from Delaware, he was a big supporter of India-US relationship.

About the November polls, Biden said that the character of the country is on the ballot. The upcoming election is the most important poll of a lifetime and that the country is currently engaged in a battle for its soul, he claimed.

Biden also slammed President Donald Trump and his administration over the handling of the coronavirus pandemic.

"Trump ignored warnings from the very beginning, refused to prepare and failed to protect the country. Not just now but throughout his presidency, undermining the very core pillars of ours, what I would argue, moral and economic strength.

"I really do believe that our country is crying out for leadership and maybe even more important, some healing. Today, we have an enormous opportunity not only to rebuild but to build back better than before. To build a better future. That's what America does," he added.

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Agencies
August 2,2020

New Delhi, Aug 2: Union Home Minister Amit Shah today tested positive for COVID-19 coronavirus infection and has been admitted to a hospital. 

Shah took to social media today to inform about his infection. “I have tested positive but my health is fine," he said, adding that he has been hospitalised on the assistance of doctors. 

The Union Home Minister also appealed to those who came into close contact with him in the last few days to get themselves tested for COVID-19.

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News Network
January 22,2020

New Delhi, Jan 22: Delhi Chief Minister Arvind Kejriwal has assets worth Rs 3.4 crore, an increase of Rs 1.3 crore from 2015, according to his election affidavit.

Kejriwal's total assets were worth Rs 2.1 crore in 2015.

The cash and fixed deposits of Kejriwal's wife Sunita Kejriwal increased from Rs 15 lakh in 2015 to Rs 57 lakh in 2020.

A party functionary said Rs 32 lakh worth cash and fixed deposits have been received by Sunita Kejriwal as voluntary retirement benefits while the rest are savings.

The cash and fixed deposits of the chief minister increased from Rs 2.26 lakh in 2015 to Rs 9.65 lakh in 2020.

There was no change in the value of immovable assets of his wife while Kejriwal's immovable assets' worth increased from Rs 92 lakh to Rs 177 lakh.

The party functionaries said increase in Kejriwal's immovable assets' worth is due to the increased valuation of the same asset as in 2015.

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