Babri verdict will strengthen India’s unity and integrity: Amit Shah

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, Jun 11: Petrol and diesel prices on Thursday were hiked by 60 paise per litre each - the fifth straight daily increase in rates since oil PSUs ended an 82-day hiatus in rate revision.

Petrol price in Delhi was hiked to Rs 74 per litre from Rs 73.40 while diesel rates were increased to Rs 72.22 a litre from Rs 71.62, according to a price notification of state oil marketing companies.

Rates have been increased across the country and vary from state to state depending on the incidence of local sales tax or VAT.

This is the fifth daily increase in rates in a row since oil companies on Sunday restarted revising prices in line with costs, after ending an 82-day hiatus.

In five hikes, petrol price has gone up by Rs 2.74 per litre and diesel by Rs 2.83.

Jammu, Jan 6: Union Minister Jitendra Singh on Sunday said India is the only shelter for religiously persecuted Hindus, Sikhs and other minorities who come from Pakistan, Bangladesh or Afghanistan, for the safety of their life and honour.

"India owes responsibility towards the minorities living in these countries which proclaim Islam as their state religion," Singh said here while launching the BJP's countrywide 10-day mass contact drive to spread awareness about the Citizenship Amendment Act (CAA).

Accompanied by senior party colleagues, including former deputy chief minister Kavinder Gupta and former minister Sat Sharma, he began by visiting the house of veteran columnist, writer and Padmashri awardee K L Pandita, where he spent time with them discussing the Act.

Later, he visited prominent social activist Amjad Mirza, eminent Sikh religious leader Baba Swaranjit Singh, retired High Court judge Justice G D Sharma, veteran journalist and former bureau head of Hind Samachar group Gopal Sachar, retired principal of Jammu government medical college Subhash Gupta, social activist and president of Peoples' Forum Ramesh Sabharwal, among others.

During his interaction with them, the Minister of State in the Prime Minister's Office claimed that Congress leaders and their allies protesting against the Act are doing so without "conviction".

He opined that if a "survey" was conducted among the family members of these Congress leaders, then, even they would not support their "anti-CAA stand".

"The tragedy of Congress party and contemporary leaders of Congress is that either they do not read their own history or are blissfully ignorant of the statements made by their own party patriarchs and former prime ministers," he said.

The minister recalled that the Nehru-Liaquat Pact of 1950 was inspired by the realisation on the part of the then Congress government headed by prime minister Jawaharlal Nehru that minorities, particularly Hindus, were not getting a fair deal in Pakistan.

"In 1949, Nehru had written a letter expressing concern about people coming in from then East Pakistan, which is now Bangladesh, and while doing so, he had referred to Hindus coming from there as 'refugees' and Muslims arriving here as 'immigrants'," Singh said.

Further, Nehru had stated that India owed a "responsibility" to these refugees, the minister said.

Referring to the opposition of senior Congress leaders Rahul Gandhi and Priyanka Gandhi to the amended legislation, the minister said someone should show them records of proceedings of the winter session of Parliament in 1950 when their great-grandfather (Nehru) had himself said that they deserved to be given citizenship and if the law was inadequate for it, then, the law should be changed.

"PM Modi should actually be given credit for showing courage and conviction to carry forward the task, which the Congress government lacked, to accomplish this," the minister opined.

Singh reiterated that a false fear psychosis against Muslims is being sought to be manufactured when there is no place as safe and comfortable to live for the community as India.

Turning the tables on the opposition to the National Population Register(NPR) and proposed National Register of Citizens (NRC), Singh pointed out that PM Modi and Union Home Minister Amit Shah have been stating that the exercise on NRC is yet to begin.

He also said that it was then Union home minister P Chidambaram, who had stated in Parliament in 2010 that NPR could be a basis for NRC.