Iran urges Muslims to unite against US, including Saudi brothers

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.

Pune, Jan 1: Maharashtra Deputy Chief Minister Ajit Pawar and Vanchit Bahujan Aghadi president Prakash Ambedkar paid tributes at the 'Jay Stambh' near here on Wednesday on the 202nd anniversary of Koregaon Bhima battle.

Lakhs of people congregate every year at the 'Jay Stambh' (victory pillar) near Koregaon Bhima village to offer tributes on the anniversary of the battle, which was fought on January 1, 1818 between the British East India Company and the Peshwa faction of the Maratha Confederacy.

Violence broke out during the bicentenary celebrations of the Koregaon Bhima battle on January 1, 2018 in which one person was killed and several others were injured.

Police have made elaborate security arrangements to ensure no untoward incident takes place during the congregation at the victory pillar, an official said.

Talking to reporters after visiting the victory pillar, Pawar said he came to offer tributes on behalf of the people of Maharashtra.

"This pillar has history and every year lakhs of people come here. Some untoward incidents took place two years ago, but the government is taking utmost care and elaborate police bandobast has been made here to ensure that no untoward incident takes place," he said.

Pawar also urged people to visit the war memorial in a peaceful manner.

"I appeal to people to come here and offer their tributes, but maintain peace and do not believe in rumours," the NCP leader said.

Prakash Ambedkar also offered his tributes at the victory pillar.

Pune Police last week issued notices to several people, including right-wing leaders Milind Ekbote and Sambhaji Bhide, and members of Kabir Kala Manch, barring them from entering the district for four days from December 29.

The notices, as part of preventive action, were issued to all those against whom cases were registered in connection with the violence two years ago.

Ekbote was arrested in March 2018 for allegedly instigating and orchestrating the violence around Koregaon Bhima.

Bhide was also booked and named in the FIR, but never arrested.

The police attributed the violence to the Elgar Parishad conclave held here on December 31, 2017, where provocative speeches were allegedly made.

They are also probing the alleged "Maoist link" of some activists to the Elgar Parishad conclave.

Several Dalit groups observe the anniversary of the Koregaon Bhima battle, in which the British defeated the Peshwas of Maharashtra.

The memorial, located at Perne village on Pune- Ahmednagar road, was constructed by the British in the memory of soldiers who died in the battle.

Dalit leaders commemorate the British victory as soldiers from the Mahar community were part of the East India Company's forces.

The Peshwas were Brahmins, and the victory is seen as a symbol of assertiveness by Dalits.

Mumbai, Mar 4: BJP leader Devendra Fadnavis on Tuesday said Maharashtra Chief Minister Uddhav Thackeray should not give "vague" replies on the 5 per cent Muslim quota issue and declare "with courage" that his government will not bring law granting reservation to the minority community.

Mr Fadnavis made the remark after Mr Thackeray, during a press conference earlier in the day, said he has not yet received the proposal regarding giving quota to Muslims and that the Shiv Sena-led government is yet to take any decision on it.

Mr Thackeray made the comments after Maharashtra Minority Affairs Minister Nawab Malik recently said in the legislative council that thestate government will provide 5 per cent quota to Muslims in education.

Mr Malik, an NCP leader, had also said the state government will ensure that a legislation to this effect is passed soon.

The NCP and the Congress, both proponents of Muslim quota, are constituents of the Sena-led Maha Vikas Aghadi government.

Asked about Mr Thackeray's remarks on the issue, Mr Fadnavis said instead of making comments at the press conference, the chief minister should make a statement in the legislature which is currently having its budget session.

The Leader of the Opposition in the assembly said that Mr Malik's opinion is the official position of the government as the minister had talked about giving quota in the council.

"So, instead of making vague comments in the press conference, the chief minister should say in the council that it is not his view (the one expressed by chief minister).

"The chief minister gave vague answers during the press conference, saying the proposal has not come to him. Your minister (Malik) only has said it," Mr Fadnavis told reporters outside the legislature building complex.

The BJP leader maintained there is no provision in the Constitution for religion-based reservation in government jobs or education.

"Say with courage that you will not give the quota, that the Constitution doesn't accept quota based on religion. Hence, we (the government) will not bring law granting quota," the former Chief Minister said.

Mr Fadnavis claimed that if given within the 50 per cent ceiling set by the Supreme Court, the Muslim quota will affect the existing reservation granted to OBCs.

"And if given outside it, it will affect Maratha quota," he added.