Six feet distancing not enough to stop coronavirus transmission in light winds: Study

News Network
May 20, 2020

London, May 20: The current physical distancing guidelines of 6 feet may be insufficient to prevent COVID-19 transmission, according to a study which says a mild cough in low wind speeds can propel saliva droplets by as much as 18 feet.

Researchers, including those from the University of Nicosia in Cyprus, said a good baseline for studying the airborne transmission of viruses, like the one behind the COVID-19 pandemic, is a deeper understanding of how particles travel through the air when people cough.

In the study, published in the journal Physics of Fluids, they said even with a slight breeze of about four kilometres per hour (kph), saliva travels 18 feet in 5 seconds.

"The droplet cloud will affect both adults and children of different heights," said study co-author Dimitris Drikakis from the University of Nicosia.

According to the scientists, shorter adults and children could be at higher risk if they are located within the trajectory of the saliva droplets.

They said saliva is a complex fluid, which travels suspended in a bulk of surrounding air released by a cough, adding that many factors affect how saliva droplets travel in the air.

These factors, the study noted, include the size and number of droplets, how they interact with one another and the surrounding air as they disperse and evaporate, how heat and mass are transferred, and the humidity and temperature of the surrounding air.

In the study, the scientists created a computer simulation to examine the state of every saliva droplet moving through the air in front of a coughing person.

The model considered the effects of humidity, dispersion force, interactions of molecules of saliva and air, and how the droplets change from liquid to vapour and evaporate, along with a grid representing the space in front of a coughing person.

Each grid, the scientists said, holds information about variables like pressure, fluid velocity, temperature, droplet mass, and droplet position.

The study analysed the fates of nearly 1,008 simulated saliva droplets, and solved as many as 3.7 million equations.

"The purpose of the mathematical modelling and simulation is to take into account all the real coupling or interaction mechanisms that may take place between the main bulk fluid flow and the saliva droplets, and between the saliva droplets themselves," explained Talib Dbouk, another co-author of the study.

However, the researchers added that further studies are needed to determine the effect of ground surface temperature on the behaviour of saliva in air.

They also believe that indoor environments, especially ones with air conditioning, may significantly affect the particle movement through air.

This work is important since it concerns safety distance guidelines, and advances the understanding of the transmission of airborne diseases, Drikakis said.

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News Network
July 22,2020

New Delhi, Jul 22: With a spike of 37,724 cases and 648 deaths reported in the last 24 hours, the total number of COVID-19 cases in India stands at 11,92,915, according to the Union Ministry of Health and Family Welfare.

The total number of cases includes 4,11,133 active cases, 7,53,050 cured/discharged/migrated and 28,732 deaths, the Health Ministry informed.

Maharashtra remains the worst affected state with 3,27,031 cases and 12,276 deaths.
The second worst-hit state, Tamil Nadu has reported 1,80,643 COVID-19 cases so far while Delhi has reported 1,25,096 cases, according to the Ministry.

Other states that have witnessed a higher number of COVID-19 positive cases include, Andhra Pradesh with 58,668 cases, Karnataka with 71,069 while Telangana has reported 47,705 COVID-19 positive cases.

Meanwhile, as per the information provided by the Indian Council of Medical Research (ICMR), the total number of samples tested up to July 21 is 1,47,24, 546 including 3,43,243 samples tested yesterday.

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News Network
June 4,2020

Jun 4: A malaria drug President Donald Trump took to try to prevent COVID-19 proved ineffective for that in the first large, high-quality study to test it in people in close contact with someone with the disease.

Results published Wednesday by the New England Journal of Medicine show that hydroxychloroquine was no better than placebo pills at preventing illness from the coronavirus.

The drug did not seem to cause serious harm, though -- about 40% on it had side effects, mostly mild stomach problems.

 “We were disappointed. We would have liked for this to work,” said the study leader, Dr. David Boulware, an infectious disease specialist at the University of Minnesota.

“But our objective was to answer the question and to conduct a high-quality study,” because the evidence on the drug so far has been inconclusive, he said.

Hydroxychloroquine and a similar drug, chloroquine, have been the subject of much debate since Trump started promoting them in March.

Hydroxychloroquine has long been used for malaria, lupus, and rheumatoid arthritis, but no large studies have shown it or chloroquine to be safe or effective for much sicker patients with coronavirus, and some studies have suggested the drugs may do harm.

Trump took a two-week course of hydroxychloroquine, along with zinc and Vitamin D, after two staffers tested positive for COVID-19, and had no ill effects, according to results of his latest physical released by his doctor Wednesday.

Federal regulators have warned against hydroxychloroquine's use except in hospitals and formal studies because of the risk of side effects, especially heart rhythm problems.

Boulware's study involved 821 people in the United States and Canada living with someone diagnosed with COVID-19 or at high risk of getting it because of their job -- doctors, nurses, ambulance workers who had significant exposure to a sick patient while not wearing full protective gear.

They were randomly assigned to get either the nutrient folate as a placebo or hydroxychloroquine for five days, starting within four days of their exposure. Neither they nor others involved in the research knew who was getting which pills.

After 14 days in the study, 12 per cent on the drug developed COVID-19 symptoms versus 14 per cent in the placebo group, but the difference is so small it could have occurred by chance, Boulware said.

“There's basically no effect. It does not prevent infection,” he said of the drug. Even if it were to give some slim advantage, “we'd want a much larger effect” to justify its use and risk of side effects for preventing illness, he said.

Results were no different among a subgroup of participants who were taking zinc or vitamin C, which some people believe might help make hydroxychloroquine more effective or fight the coronavirus.

There are some big caveats: The study enrolled people through the Internet and social media, relying on them to report their own symptoms rather than having them tracked in a formal way by doctors.

Participants were not all tested for the coronavirus but were diagnosed as COVID-19 cases based on symptoms in many cases. And not all took their medicines as directed.

The results “are more provocative than definitive,” and the drug may yet have prevention benefits if tried sooner or in a different way, Dr. Myron Cohen of the University of North Carolina at Chapel Hill wrote in a commentary in the journal.

Others were glad to see a study that had a comparison group and good scientific methods after so many weaker reports on hydroxychloroquine.

“This fits with everything else we've seen so far which suggests that it's not beneficial," said Dr. Peter Bach, director of a health policy center at Memorial Sloan Kettering Cancer Center in New York.

This study was in younger relatively healthy people, but the results “would make me very discouraged about trying to use this in older people” who are most vulnerable to serious illness from the coronavirus, Bach said.

“If it does work, it doesn't work very well.” Dr. Dan Culver, a lung specialist at the Cleveland Clinic, said there's still a chance that giving the drug sooner than four days after someone's exposure to the virus may help prevent illness.

But the study “takes 'home run' off the table” as far as hopes for the drug, he said.

The study was mostly funded by David Baszucki, founder of Roblox, a California-based game software company, and other private donors and the Minnesota university.

Boulware also is leading a study testing hydroxychloroquine for treating COVID-19. The study is finished and results are being analyzed now.

On Tuesday, the journal Lancet posted an “expression of concern” about a study it published earlier this month of nearly 15,000 COVID-19 patients on the malaria drugs that tied their use to a higher risk of dying in the hospital or developing a heartbeat problem.

Scientists have raised serious questions about the database used for that study, and its authors have launched an independent audit.

That work had a big impact: the World Health Organization suspended use of hydroxychloroquine in a study it is leading, and French officials stopped the drug's use in hospitals. On Wednesday, the WHO said experts who reviewed safety information decided that its study could resume.

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News Network
May 24,2020

Islamabad, May 24: Pakistan recorded 32 coronavirus-related deaths during the last 24 hours, taking the total number of fatalities in the country to 1,133, the health ministry said on Sunday.

The total number of COVID-19 patients in Pakistan also jumped to 54,601, it said.

Read: Coronavirus India update: State-wise total number of confirmed cases, deaths

Sindh reported the maximum number of 21,645 coronavirus cases, followed by Punjab at 19,557, Khyber-Pakhtukhwa at 7,685, Balochistan at 3,306, Islamabad at 1,592, Gilgit-Baltistan at 619 and Pakistan-occupied Kashmir (PoK) at 197.

According to the health ministry, 17,198 coronavirus patients have recovered and 473,607 tests, including 12,915 in the last 24 hours, have been conducted so far.

The government also issued strict instructions to observe social distancing while offering Eid prayer and asked people to avoid visiting relatives and hosting parties.

Eid congregations were held at open places, mosques and Eidgahs in all major cities and towns while following strict standard operating procedures (SOPs) of social distancing and other precautionary measures.

Pakistan Prime Minister's Special Assistant on Health Zafar Mirza on Friday said the deadly infection would continue to multiply if precautions are not taken.

Earlier this month, the government had announced the lifting of the countrywide lockdown imposed to curb the spread of the virus in phases, even as infections continued to rise in the country.

Prime Minister Imran Khan had cited the economic havoc the virus restrictions had wreaked on citizens as the reason behind the decision.

The prime minister on Saturday urged Pakistanis to forgo traditional Eid festivity in view of the hundreds of fatalities caused by the coronavirus and the lives lost in Friday's plane crash in Karachi.

Ninety-seven people, including nine children, were killed and two passengers miraculously survived a fiery crash when a Pakistan International Airlines plane with 99 travellers on board plunged into a densely populated residential area near the Jinnah International Airport in Karachi. Most of the victims were travelling home to celebrate Eid.

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