Hopes dashed but will fight till convicts are hanged: Nirbhaya's mother

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.

Dubai, May 7: As India begins the world’s largest evacuation mission by repatriating its overseas citizens stranded due to COVID-19, as many as 354 of them from the UAE will fly into their home country in the first two flights to Kerala today.

An Air India Express flight, which is scheduled to take off from Abu Dhabi to Kochi at 4.15 pm is the first flight, which will be followed by a Dubai-Kozhikode flight of the same airline at 5.10pm. The Indian missions in the UAE finalised the list of passengers, who were chosen based on the compelling reasons they submitted while registering their names.

Selection criteria

These include pregnant women and their accompanying family members in some instances, people with medical emergencies, workers and housemaids in distress, families with cancelled visas, bereaved family members who couldn’t attend funerals back home, a few students and stranded visitors and tourists including two brothers who got stranded in Dubai International Airport for 50 days, the missions said.

Short-listing the first passengers from among a database of more than 200,000 applicants, who include around 6,500 pregnant women, has been a mammoth task which posed several challenges for the missions, Neeraj Agrawal, Consul Press, Information and Culture at the Indian Consulate in Dubai told Gulf News.

He said the consulate set up an operations room in a tie-up with community volunteers from Kerala Muslim Cultural Centre, Indian Association Ajman, AKCAF Task Force, the BAPS Mandir, Indian People’s Forum, and Tamil Ladies’ Sangam.

 “We are trying to accommodate as many deserving people as possible. We expect the understanding of the people. It has been very difficult to sort out everyone’s urgency.”

“We cannot do a lottery system in this and we had to make sub- categories to ensure there is a mix of people with different types of urgencies.”

“Though we want to give priority to pregnant women, it is practically not possible and not good for the health and safety of the applicants to allot a lot of them on the same flight.”

He said 11 pregnant women have been issued tickets on the Dubai-Kozhikode flight.

“That is the threshold we can allow on a flight.”

Volunteer support

The consul appreciated the support of the volunteers in finalising the flight manifest.

“But our response ratio was very less. Many people whose names came up on top of the list were not willing to go on the first flights.”

Due to various constraints like this and sometimes the details of accompanying persons not readily being available, he said the mission was not able to quickly reach out to who might be really in need.

“However, we have given due consideration to people who got in touch with us with their emergency needs. At the time of issuing tickets, we had about 20 such cases.”

He said the Consul General of India in Dubai Vipul led the entire operation and Pankaj Bodkhe, consul, education, was in charge of the Dubai flight.

A big challenge

“It has been a big challenge. Our only concern is that despite our best efforts, sometimes people with more compelling reasons might have got left out on the first flights because of the volume of people who have reached out to us.”

Since there is a chance that some passengers with tickets might not be allowed to fly if they fail the medical screening including blood tests to check antibodies for COVID-19, he said some applicants in the waiting list have been asked to be on standby at the airport.

People with emergencies wishing to fly to other destinations also could not be included, he pointed out.

“We had to ask them to wait. We are unable to send them to other destinations. We can see their desperation. We feel sorry and desperate.”

He said the government is trying to add more flights to un-chartered destinations and a new flight from Dubai to Kannur has been added on May 12.

Passengers of today’s flights have been urged to reach the airport four to five hours prior to departure to facilitate the medical screening.

New Delhi, Jan 31: Slamming the BJP over the Jamia firing incident, Congress leader Priyanka Gandhi Vadra on Friday said such incidents were possible with the ruling party's leaders inciting people to shoot, and asked Prime minister Narendra Modi to answer whether he stands with violence or non-violence.   

Her attack on the government comes a day after tensions in the Jamia area spiralled on Thursday after a man fired a pistol at a group of anti-CAA protesters, injuring a student, before walking away while waving the firearm above his head and shouting "Yeh lo aazadi" amid heavy police presence in the area.

"When the BJP government ministers and party leaders incite people to shoot, give provocative speeches, then all this becomes possible. The Prime Minister should answer what kind of a Delhi he wants to build?" Priyanka Gandhi said in a tweet in Hindi.

Does the PM stand with violence or non-violence, she asked.

"Does he stand with development or with anarchy?" the Congress general secretary said.