Global experts warn of COVID-19 airborne threat
This photo taken on July 5, 2020 shows a staff member wearing protective clothing spraying disinfectant at an examinaton room ahead of the National College Entrance Examination (NCEE), known as Gaokao, in Wuhan in China's central Hubei province. China's annual nationwide college entrance examination will start on July 7, 2020.
AFP/STR
Global experts warn of COVID-19 airborne threat
Issam Ahmed (Agence France-Presse) - July 7, 2020 - 7:23am

WASHINGTON, United States — As countries ease their lockdowns, authorities need to recognize the coronavirus can spread through the air far beyond the two meters (six feet) urged in social distancing guidelines, an international group of 239 scientists said Monday.

In a comment piece that takes direct aim at the World Health Organization for its reluctance to update its advice, researchers recommended new measures including increasing indoor ventilation, installing high-grade air filters and UV lamps, and preventing overcrowding in buildings and transport. 

"There is significant potential for inhalation exposure to viruses in microscopic respiratory droplets (microdroplets) at short to medium distances (up to several meters, or room scale)," wrote the authors, led by Lidia Morawska of the Queensland University of Technology.

"Hand washing and social distancing are appropriate, but in our view, insufficient to provide protection from virus-carrying respiratory microdroplets released into the air by infected people."

The new paper appears in the Oxford Academic journal Clinical Infectious Diseases.

When an infected person breathes, speaks, coughs or sneezes, they expel droplets of various sizes. 

Those above five to ten micrometers — which is less than the width of a typical human head hair — fall to the ground in seconds and within a meter or two.

Droplets under this size can become suspended in the air in what is called an "aerosol," remaining aloft for several hours and traveling up to tens of meters.

There has been a debate in the scientific community about how infectious microdroplets are in the context of COVID-19.

For the time being the WHO advises that the potential for infection from an aerosol occurs "in specific circumstances"  mainly in hospitals, for example when a tube is placed down a patient's airway.

On the other hand, some studies of particular spreading events suggest that aerosolization and microdroplet transmission can happen in a variety of settings.

The air flow from an air conditioning unit appeared to waft the coronavirus to several tables in a Chinese restaurant in January where patrons became infected, according to a study that appeared in Emerging Infectious Diseases.

Another study that appeared in a report by the Centers for Disease Control and Prevention indicated that the virus was spread by microdroplets from people singing during a choir practice in Washington state in March.

Fifty-three people fell ill at that event and two died.

That is in addition to the fact that bars jam-packed with people have also emerged as hotspots of contagion, with droplets of all sizes believed to contribute to the spread.

Cath Noakes, a professor of environmental engineering for buildings at the University of Leeds, who contributed to the paper, said COVID-19 doesn't spread in the air as easily as measles or tuberculosis, but is a threat nonetheless.

"COVID-19 is more likely to be 'opportunistically' airborne and therefore poses a risk to people who are in the same room for long periods of time," she added.

The WHO advice is out of step with both the US CDC and its European counterpart.

"We are aware of the article and are reviewing its contents with our technical experts," the WHO said in response to the new commentary.

'Precautionary principle'

The authors recognized that the evidence for microdroplet transmission was "admittedly incomplete," but argued that the evidence for large droplets and surface transmission was also incomplete yet still formed the basis for health guidelines.

"Following the precautionary principle, we must address every potentially important pathway to slow the spread of COVID-19," they wrote.

Put another way, "absence of evidence is not evidence of absence," said Julian Tang, an associate professor of respiratory sciences at the University of Leicester who contributed to the commentary.

"The WHO say that there is insufficient evidence to prove aerosol/airborne transmission of SARS-CoV-2 is happening. We are arguing that there is insufficient proof that aerosol/airborne transmission does not occur," he said.

AIRBORNE NOVEL CORONAVIRUS
As It Happens
LATEST UPDATE: November 26, 2020 - 5:37pm

Follow this page for updates on a mysterious pneumonia outbreak that has struck dozens of people in China.

November 26, 2020 - 5:37pm

Russia on Thursday registered record numbers for daily infections and deaths from the coronavirus for the second time in less than a week. 

Health officials reported 25,487 new infections, bringing the national total to 2,187,990 cases since the beginning of the pandemic — the fifth-highest caseload in the world.

Health authorities also reported 524 deaths, raising Russia's total fatalities from COVID-19 to 38,062. — AFP

November 26, 2020 - 2:14pm

South Korea reported its highest daily number of coronavirus cases since March on Thursday, with a surge of new infections sparking fears of a major third wave.

Officials announced 583 new cases after several weeks of fresh infections ranging between around 100 and 300.

The latest cases have mostly been clusters at offices, schools, gyms and small gatherings in the greater Seoul area, the Korea Disease Control and Prevention Agency said.

New infections also emerged within the military, including dozens of newly enlisted soldiers at a boot camp — prompting the defense ministry to bolster its virus measures. — AFP

November 26, 2020 - 1:29pm

South Korea reported its highest daily number of coronavirus cases since March on Thursday, with a surge of new infections sparking fears of a major third wave.

Officials announced 583 new cases after several weeks of fresh infections ranging between around 100 and 300.

The latest cases have mostly been clusters at offices, schools, gyms and small gatherings in the greater Seoul area, the Korea Disease Control and Prevention Agency said. — AFP

November 26, 2020 - 8:31am

The coronavirus pandemic is no excuse for not getting enough exercise, the World Health Organization says Wednesday, warning that even before the crisis many were getting too little physical activity. 

In an update of its physical activity guidelines, the UN health agency stressed that exercise was vital to physical and mental health, while sedentary behaviour can have serious repercussions.

"WHO urges everyone to continue to stay active through the Covid-19 pandemic," the agency's head of health promotion Ruediger Krech told reporters.

"If we do not remain active, we run the risk of creating another pandemic of ill-health as a result of sedentary behavior." — AFP

November 25, 2020 - 8:29pm

The coronavirus crisis has hit Italy's already historically-low birth rate, new projections from the national statistics agency reveal. 

Italy had last year already recorded its lowest number of births for 150 years, at 420,000, but this could fall to 408,000 in 2020 and 393,000 in 2021, according to Istat.

The projections were presented by Istat chief, Gian Carlo Blangiardo, to lawmakers on Tuesday.

"The climate of fear and uncertainty as well as financial difficulties... caused by recent events will have a negative effect on the fertility of Italian couples," he said. — AFP

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