Resolving people's issues priority: Aaditya Thackeray

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, Apr 23: The nationwide lockdown in India which started about a month ago has impacted nearly 40 million internal migrants, the World Bank has said.

The lockdown in India has impacted the livelihoods of a large proportion of the country's nearly 40 million internal migrants. Around 50,000 60,000 moved from urban centers to rural areas of origin in the span of a few days, the bank said in a report released on Wednesday.

According to the report -- 'COVID-19 Crisis Through a Migration Lens' -- the magnitude of internal migration is about two-and-a-half times that of international migration.

Lockdowns, loss of employment, and social distancing prompted a chaotic and painful process of mass return for internal migrants in India and many countries in Latin America, it said.

Thus, the COVID-19 containment measures might have contributed to spreading the epidemic, the report said.

Governments need to address the challenges facing internal migrants by including them in health services and cash transfer and other social programmes, and protecting them from discrimination, it said.

World Bank said that coronavirus crisis has affected both international and internal migration in the South Asia region.

As the early phases of the crisis unfolded, many international migrants, especially from the Gulf countries, returned to countries such as India, Pakistan, and Bangladesh until travel restrictions halted these flows.

Some migrants had to be evacuated by governments, such as those of China and Iran, it said.

Before the coronavirus crisis, migrant outflows from the region were robust, the report said.

The number of recorded, primarily low-skilled emigrants from India and Pakistan rose in 2019 relative to the prior year but is expected to decline in 2020 due to the pandemic and oil price declines impacting the Gulf countries.

In India, the number of low-skilled emigrants seeking mandatory clearance for emigration rose slightly by eight percent to 368,048 in 2019.

In Pakistan, the number of emigrants jumped 63 per cent to 6,25,203 in 2019, largely due to a doubling of emigration to Saudi Arabia, it said.

According to the bank, migration flows are likely to fall, but the stock of international migrants may not decrease immediately, since migrants cannot return to their countries due to travel bans and disruption to transportation services.

In 2019, there were around 272 million international migrants.

The rate of voluntary return migration is likely to fall, except in the case of a few cross-border migration corridors in the South (such as Venezuela-Colombia, Nepal-India, Zimbabwe South Africa, Myanmar-Thailand), it said.

Migrant workers tend to be vulnerable to the loss of employment and wages during an economic crisis in their host country, more so than native-born workers.

Lockdowns in labour camps and dormitories can also increase the risk of contagion among migrant workers.

Many migrants have been stranded due to the suspension of transport services. Some host countries have granted visa extensions and temporary amnesty to migrant workers, and some have suspended the involuntary return of migrants, it said.

Observing that government policy responses to the COVID-19 crisis have largely excluded migrants and their families back home, the World Bank said there is a strong case for including migrants in the near-term health strategies of all countries, given the externalities associated with the health status of an entire population in the face of a highly contagious pandemic.

The Bank said governments would do well to consider short, medium and long-term interventions to support stranded migrants, remittance infrastructure, loss of subsistence income for families back home, and access to health, housing, education, and jobs for migrant workers in host/transit countries and their families back home.

The pandemic has also highlighted the global shortage of health professionals and an urgent need for global cooperation and long-term investments in medical training, it said.

New Delhi, Jan 12: A fact-finding committee of the Congress on the JNU violence on Sunday said the January 5 attack inside the university campus was "state-sponsored" and recommended Vice Chancellor M Jagadesh Kumar be dismissed and criminal investigation initiated against him.

The Congress had appointed a four-member fact-finding committee to carry out a detailed inquiry into the violence at the Jawaharlal Nehru University (JNU).

Sushmita Dev, member of the committee, said the committee recommended that Kumar should be dismissed immediately and all the appointments in faculty should be probed and independent inquiry should take place.

"Criminal investigation must take place against the VC and faculty members and the security company," the Mahila Congress chief said.

"It is clear that the attack on JNU campus was state-sponsored," Dev said.

She also demanded a complete rollback of the JNU fee hike.

The other members of the fact-finding committee are Hibi Eden, MP and former NSUI president, Syed Naseer Hussain, MP and former president of JNU NSUI and Amrita Dhawan, a former NSUI president and ex-DUSU president.

On January 5 night, masked people armed with rods and sticks stormed the JNU campus and assaulted students and faculty members, and vandalised property, leaving several people injured.

Leftist outfits and the RSS-affiliated Akhil Bharatiya Vidyarthi Parishad (ABVP) blamed each other for the violence.