5 saffron extremists including a Mangalurean are key suspects in Gauri Lankesh murder

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.

Mangaluru, Mar 12: Deputy Commissioner Sindhu B Rupesh on Thursday said that the test reports of the 35-year-old passenger from Dubai have shown no signs of either Coronavirus (COVID-19) or H1N1.

In statement issued here Ms Rupesh said that the passenger has now been discharged from the Bantwal hospital. He has been asked to stay at home quarantined for the next 14 days.

The passenger, who had been diagnosed with fever after he arrived at the airport from Dubai on March 8, had left the Government Wenlock Hospital in the early hours of March 9 refusing to undergo tests.

Later, he was traced and admitted to the hospital in Bantwal and his throat swab samples had been sent to Viral Research Diagnostic Laboratory (VRDL) in Hassan Institute of Medical Sciences.

Meanwhile, throat swab samples of six patients were also found negative for COVID-19.

As many asf 49 people were under quarantine in the district of which five have completed the 28-day cycle.

All passengers arriving by international flights and those in contact with them should voluntarily report to the district health team and undergo self-quarantine for 14 days. If there were symptoms of cough, cold and fever, they should undergo tests for COVID-19. If the reports were positive for COVID-19, then they have to stay in the isolation ward of the Government Wenlock Hospital or in the seven select private hospitals for 28 days.

Screening facility at the airport has been strengthened by posting doctors from seven private medical colleges on rotation basis. These doctors would be in addition to the medical officer at the airport. An ambulance has been placed at the airport exclusively to shift people to the hospitals, she added.

The State government has issued a notification on Wednesday authorising Deputy Commissioners to get the affected admitted by force, if necessary.

Mangaluru, Jan 2: The Muslim Central Committee of Dakshina Kannada and Udupi has dropped its plan to stage a massive protest against the contentious Citizenship (Amendment) Act and National Register of Citizens on January 4 at Mangaluru’s Nehru Maidan.

Addressing a press conference here today, committee chief K S Mohammed Masood made this announcement.

“All the 28 organisations that had decided to stage protest under the leadership of the Muslim Central Committee, have unanimously agreed to temporarily cancel the protest plan after the city police refused permission for the event,” he said.

Mr Masood requested the people, especially the youth, not to lose patience. “No one should head to Nehru Maidan on January 4 as Muslim leaders have unanimously decided to cancel the protest,” he urged.

S M Rasheed Haji, Y Abdulla Kunhi, Umar UH, Ibrahim Kodichal, B M Mumtaz Ali, Khasim H K, Mansoor Ahmed Azad and Asif Deals were present in the press meet.