Former minister, statesman B A Mohideen no more

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.

Follow latest updates on the Covid-19 pandemic here

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.

Washington, Jun 30: Researchers in China have discovered a new type of swine flu that is capable of triggering a pandemic, according to a study published Monday in the US science journal PNAS.

Named G4, it is genetically descended from the H1N1 strain that caused a pandemic in 2009.

It possesses "all the essential hallmarks of being highly adapted to infect humans," say the authors, scientists at Chinese universities and China's Center for Disease Control and Prevention.

The researchers then carried out various experiments including on ferrets, which are widely used in flu studies because they experience similar symptoms to humans -- principally fever, coughing and sneezing. 

G4 was observed to be highly infectious, replicating in human cells and causing more serious symptoms in ferrets than other viruses.

Tests also showed that any immunity humans gain from exposure to seasonal flu does not provide protection from G4.

According to blood tests which showed up antibodies created by exposure to the virus, 10.4 percent of swine workers had already been infected.

The tests showed that as many as 4.4 percent of the general population also appeared to have been exposed.

The virus has therefore already passed from animals to humans but there is no evidence yet that it can be passed from human to human -- the scientists' main worry.

"It is of concern that human infection of G4 virus will further human adaptation and increase the risk of a human pandemic," the researchers wrote.

The authors called for urgent measures to monitor people working with pigs.

"The work comes as a salutary reminder that we are constantly at risk of new emergence of zoonotic pathogens and that farmed animals, with which humans have greater contact than with wildlife, may act as the source for important pandemic viruses," said James Wood, head of the department of veterinary medicine at Cambridge University.

A zoonotic infection is caused by a pathogen that has jumped from a non-human animal into a human.

Shivaji is a great icon in Maharashtra. Different sections of society have given him very high status, though for diverse reasons. Folklores about him abound in the state. His statues, popular songs on him are very prevalent. These folk songs (Powadas) praise his multifarious actions. So it was no surprise that when Jayabhagwan Goyal, released his book, ‘Aaj ka Shivaji: Narendra Modi’, at religious-cultural meet organized by Delhi BJP, there was a strong resentment in Maharashtra. Various leaders from Maharashtra were furious. The Shiv Sena leader Sanjay Raut challenged the Shivaji’s descendent, Sambhaji Raje who is in BJP and is member of Rajya Sabha, to resign on the issue. Sambhaji Raje in turn stated that "We respect Narendra Modi, who was elected as the prime minister of the country for the second time. But neither (Narendra) Modi nor anybody else in the world can be compared with Chhatrapati Shivaji Maharaj,"

Not to be left behind Jitendra Awhad of NCP felt Modi-BJP are insulting the pride of Maharashtra. It is not the first time that controversy is erupting around the Maharashtra warrior of medieval period. Earlier we had seen Sambhaji Brigrade demanding the ban on James Laine book, Shivaji: ‘A Hindu King in an Islamic Kingdom’, for its objectionable content. Bhandarkar Institute in Pune, which had helped James Laine in his research, was also vandalized. At another level there was a talk that Babasaheb Purandare, a Brahmin, who has written some popular material on Shivaji will be made as the Chairman of the committee for statue of Shivaji. Maratha Mahasangh and Shiv Dharm officials objected to a Brahmin heading the committee for a statue for the Maratha warrior. The caste angel in Shivaji’s case is coming to the fore from quite some time.

While there is no dearth of controversies around Shivaji, it is also true that each political tendency has created Shivaji’s image from their political point of view. Who was the real Shivaji, is the question. One can see two clear streams of projection in this matter. On one hand there is an attempt to present Shivaji as the anti Muslim King, a king who was respecting Cows and Brahmins (Go Brahman pratipalak). This view was brought forward from the times of Lokmanya Tilak and picked up by Hindu nationalists, who have been looking for icons in history to suit their political agenda. Nathram Godse, while criticizing Gandhi says that Gandhi’s nationalism was dwarf in front of the one of Shivaji or Rana Pratap.

In tune with this the Hindu nationalists are promoting both these as icons of Hindu nationalism and giving anti-Muslim slant to the whole discourse. This discourse also hides in this the Brahmanical agenda of Hindu nationalism as Cows and Brahmins are presented as the central object of veneration by Shivaji. This image of Shivaji fits well into the current agenda of Hindu nationalists, being spearheaded by RSS Combine.

It is because of this that for seeking votes in Mumbai Narendra Modi on the eve of 2014 elections stated that Shivaji attacked Surat to plunder the treasury of Aurangzeb. This also presents Shivaji-Aurangzeb, Shivaji-Afzal Khan interactions as battle between Hindus and Muslims. The truth is that Surat was plundered for its wealth as it was a rich port city and Bal Samant’s book on the topic gives in depth description of the same. It is noteworthy that Shivaji began his real career of conquest in 1656 when he conquered Javli from the Maratha Chief Chandra Rao More. He took over the treasures of this kingdom. That it was not a Hindu Muslim battle becomes clear when we know that in confrontation with Aurangzeb it was Mirza Raja Jaisingh who was negotiating and engaging with Shivaji on behalf of Aurangzeb. And Shivaji had Muslim officers like Kazi Haider as confidential secretary and many Muslim Generals in his army.

Darya Sarang was chief of armor division, Daulat Khan was in-charge of his naval division; Ibrahim Khan was another general of significance in his army.  This mixed up administration just shows that the kings were not having Hindu or Muslim administration depending on their religion. In the confrontation between Shivaji and Afzal Khan, Rustam-e-Jaman was Shivaji’s side and Afzal Khan had Krisnaji Bhaskar Kulkarni on his side.

As far as Shivaji’s popularity is concerned it was due to his being a King with welfare of his subjects in his mind. He lightened the burden of taxation on the average peasants, and reduced the domination of landlords over the serfs. This picture of Shivaji is well documents in the booklets by Com. Govind Pansare (Who was Shivaji) and Jayant Gadkari (Shivaji: Ek Lok Kalyankari Raja- Shivaji: King doing People’s Welfare). He did not belong to the warrior caste so Brahmins had refused to coronate him, for which purpose Gaga Bhatt a Brahmin from Kashi was brought in with heavy fees. Teesta Setalvad’s hand book on History for teachers underlined this fact.

Today while BJP-Brahmanical forces want to present Shivaji as worshipper of Brahmins and cows, the non upper caste have seen through the game. As such it was Jotirao Phule who brought forward the caste angel of Shivaji as he wrote Powada (Poem) in his honor and today dalit Bahujan are not toeing Hindu Nationalist projection on the issue.

The likes of Jayabhagwan Goyal of BJP as such are trying to give two messages through such attempts. One hand they want to paint Shivaji in anti Muslim and Brahmanical color, they also want to give the subtle message of similarity of this presentation of Shivaji with what Modi is doing. Non BJP forces have seen this game and want to present the other picture of Shivaji, which was highlighted by the likes of Jotirao Phule and which today many of those standing for rights of dalit-Bahujan are trying to articulate. The criticism of the said, book, since withdrawn is on these twin aspects. One about the picture of Shivaji who was concerned about welfare of the farmers, and two his respect for people of all religions.