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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News Network
March 7,2020

Srinagar, Mar 7: Two more accused, including a man who allegedly bought chemicals online for making improvised explosive device (IED) to be used in an attack on a convoy of the Central Reserve Police Force (CRPF) in Jammu and Kashmir's Pulwama last year, were arrested by the National Investigation Agency (NIA) on Friday, an official said.

The terror attack left 40 CRPF personnel dead in south Kashmir's Pulwama last year.

Waiz-ul-Islam, 19, from Srinagar and Mohammad Abbass Rather, 32, from Pulwama were arrested by the NIA, taking the number of those arrested in the case in the past week to five.

"During initial interrogation, Islam disclosed that he used his Amazon online shopping account to procure chemicals for making IEDs, batteries and other accessories on the directions of Pakistani Jaish-e-Mohammed (JeM) terrorists," the official said.

He said Islam personally delivered the items to the JeM terrorists after buying them online as a part of the conspiracy to carry out the attack.

"Rather is an old overground worker of the JeM. He has disclosed that he gave shelter at his home to Jaish terrorist and IED expert Mohd Umar after he came to Kashmir in April-May 2018," the official said.

Rather also sheltered other JeM terrorists - suicide bomber Adil Ahmad Dar, Sameer Ahmed Dar and Kamran, a Pakistani -- at his house before the Pulwama attack, the official said.

"He also facilitated safe shelter for the JeM terrorists, including Adil, at the house of accused Tariq Ahmed Shah and his daughter Insha Jan of Hakripora, who were arrested on March 3," the official said.

He said Islam and Rather will be produced before the NIA special court in Jammu on Saturday, while further investigation in the case continues. The NIA took over the case to probe the conspiracy behind the February 14, 2019, attack in Pulwama.

The last video of Adil, which was released by the JeM from Pakistan after the terror attack, was filmed at the home of Tariq Ahmed Shah. On February 28, the NIA achieved a major breakthrough in the case when it arrested 22-year-old Shakir Bashir Magrey, a furniture shop owner and resident of Pulwama.

Magrey had given shelter and other logistical assistance to suicide bomber Adil. He was introduced to Adil in mid-2018 by Pakistani terrorist Mohammad Umar Farooq and he became a full-time OGW of the JeM.

The explosives used in the attack were determined through forensic probe to be ammonium nitrate, nitro-glycerin and RDX. During investigation into the attack, the identity of the suicide bomber to be Adil Ahmad Dar was confirmed through DNA matching with that of his father.

The other key terrorists involved in the attack have been found to be JeM's south Kashmir divisional head Muddasir Ahmad Khan, killed in an operation by the security forces on March 11 last year; Pakistani terrorists Muhammad Umar Farooq and IED expert Kamran, both killed on March 29 last year; the owner of the car Sajjad Ahmad Bhat, a resident of Anantnag who was killed on June 16 last year, and Qari Yassir, JeM's commander for Kashmir who was killed on January 25 this year.

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News Network
February 3,2020

Beijing, Feb 3: The first batch of patients arrived on Monday at a specialised hospital built in just 10 days as part of China's intensive efforts to fight a new virus.

Huoshenshan Hospital and a second facility with 1,500 beds that's due to open this week were built by construction crews who are working around the clock in Wuhan, the city in central China where the outbreak was first detected in December.

The Wuhan treatment centres mark the second time Chinese leaders have responded to a new disease by building specialised hospitals almost overnight. As severe acute respiratory syndrome, or SARS, spread in 2003, a facility in Beijing for patients with that viral disease was constructed in a week.

The first batch of patients arrived at the Huoshenshan Hospital at 10 am on Monday, according to state media. The reports gave no details of the patients' identities or conditions.

The ruling Communist Party's military wing, the People's Liberation Army, sent 1,400 doctors, nurses and other personnel to staff the Wuhan hospital, the official Xinhua News Agency said. The government said earlier some have experience fighting SARS and other outbreaks.

Authorities have cut most road, rail and air access to Wuhan and surrounding cities, isolating some 50 million people, in efforts to contain the viral outbreak that has sickened more than 17,000 and killed more than 360 people.

The Huoshenshan Hospital was built by a 7,000-member crew of carpenters, plumbers, electricians and other specialists, according to the Xinhua News Agency.               Photos in state media showed workers in winter clothing, safety helmets and the surgical-style masks worn by millions of Chinese in an attempt to avoid contracting the virus.

About half of the two-storey, 600,000-square-foot building is isolation wards, according to the government newspaper Yangtze Daily. It has 30 intensive care units.

Doctors can talk with outside experts over a video system that links them to Beijing's PLA General Hospital, according to the Yangtze Daily. It said the system was installed in less than 12 hours by a 20-member "commando team" from Wuhan Telecom Ltd.

The building has specialised ventilation systems and double-sided cabinets that connect patient rooms to hallways and allow hospital staff to deliver supplies without entering the rooms.

The hospital received a donation of "medical robots" from a Chinese company for use in delivering medicines and carrying test samples, according to the Shanghai newspaper The Paper.

In other cities, the government has designated hospitals to handle cases of the new virus.

In Beijing, the Xiaotangshan Hospital built in 2003 for SARS is being renovated by construction workers. The government has yet to say whether it might be used for patients with the new disease.

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Agencies
February 10,2020

Washington D.C, Feb 10: Children's vulnerability towards depression, anxiety, impulsive behaviour, and poor cognitive performance could be determined by considering the hours of sleep they manage to get.

Sleep states are active processes that support the reorganisation of brain circuitry. This makes sleep especially important for children, whose brains are developing and reorganising rapidly.

In a study by researchers from the University of Warwick -- recently published in the journal Molecular Psychiatry -- cases of 11,000 children aged between 9 and 11 years from the Adolescent Brain Cognitive Development dataset were analyzed to find out the relationship between sleep duration and brain structure.

The study was carried out by researchers Professor Jianfeng Feng, Professor Edmund Rolls, Dr. Wei Cheng and colleagues from the University of Warwick's Department of Computer Science and Fudan University.

Measures of depression, anxiety, impulsive behaviour and poor cognitive performance in the children were associated with shorter sleep duration. Moreover, the depressive problems were associated with short sleep duration one year later.

The reduced brain volume of areas such as orbitofrontal cortex, prefrontal, and temporal cortex, precuneus, and supramarginal gyrus was found to be associated with the shorter sleep duration.

Professor Jianfeng Feng, from the University of Warwick's Department of Computer Science, comments: "The recommended amount of sleep for children 6 to 12 years of age is 9-12 hours. However, sleep disturbances are common among children and adolescents around the world due to the increasing demand on their time from school, increased screen time use, and sports and social activities."

A previous study showed that about 60 per cent of adolescents in the United States receive less than eight hours of sleep on school nights.

Professor Jianfeng Feng further added: "Our findings showed that the total score for behavior problems in children with less than 7 hours sleep was 53 per cent higher on average and the cognitive total score was 7.8 per cent lower on average than for children with 9-11 hours of sleep. It highlights the importance of enough sleep in both cognition and mental health in children."

Professor Edmund Rolls from the University of Warwick's Department of Computer Science also commented: "These are important associations that have been identified between sleep duration in children, brain structure, and cognitive and mental health measures, but further research is needed to discover the underlying reasons for these relationships."

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