Coronavirus airborne: What we should do now

International New York Times
July 7, 2020

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.

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Agencies
July 2,2020

The American pharmaceutical giant Pfizer Inc. and the European biotechnology company BioNTech SE have conducted an experimental trial of a COVID-19 vaccine candidate and found it to be safe, well-tolerated, and capable of generating antibodies in the patients.

The study, which is yet to be peer-reviewed, describes the preliminary clinical data for the candidate vaccine -- nucleoside-modified messenger RNA (modRNA), BNT162b1.

It said the amount of antibodies produced in participants after they received two shots of the vaccine candidate was greater than that reported in patients receiving convalescent plasma from recovered COVID-19 patients.

"I was glad to see Pfizer put up their phase 1 trial data today. Virus neutralizing antibody titers achieved after two doses are greater than convalescent antibody titers," tweeted Peter Hotez, a vaccine scientist from Baylor College of Medicine in the US, who was unrelated to the study.

Researchers, including those from New York University in the US, who were involved in the study, said the candidate vaccine enables human cells to produce an optimised version of the receptor binding domain (RBD) antigen -- a part of the spike (S) protein of SARS-CoV-2 which it uses to gain entry into human cells.

"Robust immunogenicity was observed after vaccination with BNT162b1," the scientists noted in the study.

They said the program is evaluating at least four experimental vaccines, each of which represents a unique combination of mRNA format and target component of the novel coronavirus, SARS-CoV-2.

Based on the study's findings, they said BNT162b1 could be administered in a quantity that was well tolerated, potentially generating a dose dependent production of immune system molecules in the patients.

The research noted that patients treated with the vaccine candidate produced nearly 1.8 to 2.8 fold greater levels of RBD-binding antibodies that could neutralise SARS-CoV-2.

"We are encouraged by the clinical data of BNT162b1, one of four mRNA constructs we are evaluating clinically, and for which we have positive, preliminary, topline findings," said Kathrin U. Jansen, study co-author and Senior Vice President and Head of Vaccine Research & Development, Pfizer.

"We look forward to publishing our clinical data in a peer-reviewed journal as quickly as possible," Jansen said.

According to Ugur Sahin, CEO and Co-founder of BioNTech, and another co-author of the study, the preliminary data are encouraging as they provide an initial signal that BNT162b1 is able to produce neutralising antibody responses in humans.

He said the immune response observed in the patients treated with the experimental vaccine are at, or above, the levels observed from convalescent sera, adding that it does so at "relatively low dose levels."

"We look forward to providing further data updates on BNT162b1," Sahin said.

According to a statement from Pfizer, the initial part of the study included 45 healthy adults 18 to 55 years of age.

It said the priliminary data for BNT162b1 was evaluated in 24 subjects who received two injections of 10 microgrammes ( g) and 30 g -- 12 subjects who received a single injection of 100 g, and 9 subjects who received two doses of a dummy vaccine.

The study noted that participants received two doses, 21 days apart, of placebo, 10 g or 30 g of BNT162b1, or received a single dose of 100 g of the vaccine candidate.

According to the scientists, the highest neutralising concentrations of antibodies were observed seven days after the second dose of 10 g, or 30 g on day 28 after vaccination.

They said the neutralising concentrations were 1.8- and 2.8-times that observed in a panel of 38 blood samples from people who had contracted the virus.

In all 24 subjects who received two vaccinations at 10 g and 30 g dose levels, elevation of RBD-binding antibody concentrations was observed after the second injection, the study noted.

It said these concentrations are 8- and 46.3-times the concentration seen in a panel of 38 blood samples from those infected with the novel coronavirus.

At the 10 g or 30 g dose levels, the scientists said adverse reactions, including low grade fever, were more common after the second dose than the first dose.

According to Pfizer, local reactions and systemic events after injection with 10 g and 30 g of BNT162b1 were "dose-dependent, generally mild to moderate, and transient."

It said the most commonly reported local reaction was injection site pain, which was mild to moderate, except in one of 12 subjects who received a 100 g dose, which was severe.

The study noted that there was no serious adverse events reported by the patients.

Citing the limitations of the research, the scientists said the immunity generated in the participants in the form of the T cells and B cells of their immune system, and the level of immunity needed to protect one from COVID-19 are unknown.

With these preliminary data, along with additional data being generated, Pfizer noted in the statement that the two companies will determine a dose level, and select among multiple vaccine candidates to seek to progress to a large, global safety and efficacy trial, which may involve up to 30,000 healthy participants if regulatory approval to proceed is received.

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News Network
February 24,2020

New Delhi, Feb 24: The shared values between India and the US are "discrimination, bigotry, and hostility towards refugees and asylum seekers", Amnesty International USA said in a joint statement with Amnesty International India ahead of US President Donald Trump's visit to India on Monday.

Trump, accompanied by his wife Melania, daughter Ivanka and son-in-law Jared Kushner as well as senior officials of his administration, landed in Ahmedabad on the first leg of his two-day visit to India.

"Anti-Muslim sentiment permeates the policies of both U.S. and Indian leaders. For decades, the U.S.-India relationship was anchored by claims of shared values of human rights and human dignity. Now, those shared values are discrimination, bigotry, and hostility towards refugees and asylum seekers,” Margaret Huang, Amnesty International USA’s executive director, was quoted as saying in the statement.

It was a reference to the anti-CAA protests in India, the internet lockdown in Jammu and Kashmir and the Muslim ban expansion by President Trump affecting Nigeria, Eritrea, Myanmar, Kyrgyzstan, Sudan and Tanzania, the statement said.

It added that Amnesty International USA’s researchers travelled to Lebanon and Jordan to conduct nearly 50 interviews with refugees that as a result of the previous version of the ban have been stranded in countries where they face restrictive policies, increasingly hostile environments, and lack the same rights as permanent residents or citizens.

The statement also came down hard on the Indian government, hitting out at the Citizenship (Amendment) Act (CAA) 2019 and saying it legitimises discrimination based on religious grounds.

It criticised statements such as “identify them (the protestors) by their clothes” or “shoot the traitors” by Prime Minister Modi and his party workers. Such remarks "peddled the narrative of fear and division that has fuelled further violence", it said.

“The internet and political lockdown in Kashmir has lasted for months and the enactment of CAA and the crackdown on protests has shown a leadership that is lacking empathy and a willingness to engage. We call on President Trump and Prime Minister Modi to work with the international community and address our concerns in their bilateral conversations,” Avinash Kumar, executive director, Amnesty International India said in the statement.

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News Network
June 19,2020

Jun 19: Billionaire Mukesh Ambani on Friday announced that his oil-to-telecom conglomerate Reliance Industries is now net debt-free after raising a record Rs 1.69 lakh crore from global investors and a rights issue in under two months.

Reliance raised Rs 1.15 lakh crore from global tech investors by selling a little less than a quarter of the firm's digital arm, Jio Platforms Ltd, and another Rs 53,124.20 crore through a rights issue in the past 58 days.

Taken together with last year's sale of 49 per cent stake in fuel retailing venture to BP Plc of UK for Rs 7,000 crore, the total fund raised is in excess of Rs 1.75 lakh crore, the company said in a statement.

Reliance had a net debt of Rs 1,61,035 crore as on March 31, 2020. "With these investments, RIL has become net debt-free," it said.

"I have fulfilled my promise to the shareholders by making Reliance net debt-free much before our original schedule of March 31, 2021," Ambani said.

Jio Platforms - which houses the country's youngest but largest telecom firm Reliance Jio, raised Rs 1,15,693.95 crore from leading global investors including Facebook, Silver Lake, Vista Equity Partners, General Atlantic, KKR, Mubadala, ADIA, TPG, L Catterton and PIF since April 22, 2020.

Saudi Arabian sovereign wealth fund PIF buying 2.32 per cent stake in the unit for Rs 11,367 crore on June 18 "marks the end of Jio Platforms' current phase of induction of financial partners," the statement said.

Alongside, Reliance launched India's biggest right issue, which was subscribed to 1.59 times.

Though the rights issue size was Rs 53,124 crore, the company has got only 25 per cent of the money as the remaining is to be paid only next fiscal.

Ambani had at the company's annual general meeting on August 12, 2019, announced a roadmap for Reliance to become a net debt-free company before March 31, 2021.

"We have a very clear roadmap to becoming a zero net-debt company within the next 18 months that is by March 31, 202," he had said last year highlighting strong interest from strategic and financial investors in consumer businesses, Jio and Reliance Retail.

In the statement on Friday, he said he was both delighted and humbled to announce the fulfillment of the promise.

"Exceeding the expectations of our shareholders and all other stakeholders, again and yet again, is in the very DNA of Reliance," he said.

"Therefore, on the proud occasion of becoming a net debt-free company, I wish to assure them that Reliance in its Golden Decade will set even more ambitious growth goals, and achieve them," he added.

He said over the past few weeks, phenomenal interest was received from the global financial investor community in partnering with Jio.

"As our fundraising milestone from financial investors is achieved, we sincerely thank the marquee group of financial partners and warmly welcome them into Jio Platforms," he said.

"I also express my heartfelt gratitude to all the retail and institutional investors, both domestic and foreign, for their overwhelming participation in our record-setting Rights Issue," he added.

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