Gorakhpur tragedy: Dr Kafeel Khan slams Yogi Adityanath for telling ‘blatant lies’

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 10: The Enforcement Directorate (ED) on Wednesday brought back over 2,300 kg of polished diamonds and pearls worth Rs 1,350 crore of firms belonging to Nirav Modi and Mehul Choksi from Hong Kong, officials said.

Out of the 108 consignments that landed at Mumbai, 32 belong to overseas entities "controlled" by Modi while the rest are of Mehul Choksi firms.

Both the businessmen are being probed by the ED under the Prevention of Money Laundering Act (PMLA) in connection with an over USD 2 billion alleged bank fraud at a PNB branch in Mumbai.

The valuables include polished diamonds, pearls and silver jewellery, and is worth Rs 1,350 crore. 

The ED completed "all legal formalities" with authorities in Hong Kong to bring back these valuables, the agency said.

These will formally seized under the PMLA now, it said.

New Delhi, Apr 8: The death toll due to the novel coronavirus rose to 149 and the number of cases to 5,194 in the country on Wednesday, according to the Union Health Ministry.

While the number of active COVID-19 cases is 4,643, as many as 401 people were cured and discharged and one had migrated, it said.

The total number of cases include 70 foreign nationals.

According to the ministry's data updated at 9 a.m., 25 new deaths have been reported since Tuesday.

Sixteen deaths were reported from Maharashtra, two each from Delhi, West Bengal, Haryana and Tamil Nadu and one from Andhra Pradesh.

Maharashtra has reported the most coronavirus deaths at 64, followed by Gujarat  and Madhya Pradesh at 13 each and Delhi at 9.

Telengana, Punjab and Tamil Nadu have reported seven fatalities each.

West Bengal has registered five deaths, Karnataka and Andhra Pradesh have reported four each, Uttar Pradesh, Haryana and Rajasthan have recorded three deaths each.

Two deaths each have been reported from Jammu and Kashmir and Kerala.

Bihar, Himachal Pradesh and Odisha reported one fatality each, according to the health ministry data.

However, a PTI tally of figures reported by various states as on Tuesday 9.45 p.m. showed 5,192 testing positive across the country and at least 162 deaths.

There has been a lag in the Union Health Ministry figures, compared to the numbers announced by different states, which officials attribute to procedural delays in assigning the cases to individual states.

The highest number of confirmed cases in the country are from Maharashtra at 1018, followed by Tamil Nadu at 690 and Delhi with 576 cases.

Telengana has reported 364 COVID-19 cases followed by Kerala at 336.

Rajasthan has 328 cases, Uttar Pradesh has 326 and Andhra Pradesh reported 305 coronavirus cases.

Novel coronavirus cases have risen to 229 in Madhya Pradesh, 175 in Karnataka and 165 in Gujarat.

Haryana has 147 cases, Jammu and Kashmir has 116, West Bengal has 99 and Punjab has 91 positive patients so far. Odisha has reported 42 coronavirus cases.

Thirty- eight people were infected with the virus in Bihar while Uttarakhand has 31 patients and Assam 27.

Chandigarh  and Himachal Pradesh have 18 cases each while Ladakh has 14 positive patients so far.

Ten cases each have been reported from the Andaman and Nicobar Islands and Chhattisgarh. 

Goa has reported seven COVID-19 infections, followed by Puducherry at five cases. Jharkhand has reported four cases and Manipur two. 

Tripura, Mizoram and Arunachal Pradesh have reported one case each.

"State-wise distribution is subject to further verification and reconciliation," the ministry said on its website.