Dissident scientists spent a year convincing the World Health Organization that the virus that causes COVID-19 spreads through the air.

click image to enlarge; original here; backed up here

In March 2020, the World Health Organization used social media to aggressively deny that the virus that causes COVID-19 stays aloft in the air.

INCORRECT claimed the WHO on Twitter. FACT CHECK: COVID-19 is NOT airborne. The WHO said that “droplets generated when an infected person coughs, sneezes or speaks” are “too heavy to hang in the air. They quickly fall on floors or surfaces.” As long as people remained 3 feet (1 meter) apart from each other, there was no risk of breathing in the virus, it insisted.

But the WHO was wrong. As two recent reports explain, it has now quietly reversed itself. Very quietly.

In a 30-minute read over at Wired magazine, Megan Molteni recounts events through the eyes of Linsey Marr. Along with 35 other aerosol scientists, Marr participated in a zoom meeting with WHO officials six days after its NOT airborne tweet. Together, they tried to explain to those making COVID-related decisions that a growing list of superspreader events implied people were catching the virus even when they kept their distance from each other indoors.

This meant the virus was almost certainly airborne. It meant the great outdoors was a safer place to be, and that good ventilation was important.

Recalling a WHO expert rudely cutting off a senior atmospheric physicist during that zoom meeting, Marr says, “It felt like they had already made up their minds.” Journalist Molteni explains the bigger picture:

The distinction between droplet and airborne transmission has enormous consequences. To combat droplets, a leading precaution is to wash hands frequently with soap and water. To fight infectious aerosols, the air itself is the enemy.

For decades, the medical community has believed three things:

1. respiratory diseases are spread primarily via droplets (defined as particles larger than 5 microns)
2. these droplets fall to the floor quickly rather than circulating in the air
3. particles smaller than 5 microns – called microdropletsdroplet nuclei, or aerosols – remain airborne, but are of marginal concern

Marr, who has a doctorate in civil and environmental engineering, knew from air samples she’d collected in day care centers and elsewhere long before the pandemic appeared that these ideas are mistaken: Particles larger than 5 microns do stay afloat, she says, “depending on heat, humidity, and airspeed.”

Following the Zoom call with the WHO, Marr, some colleagues, and a graduate student became detectives in an attempt to track down the original source of these dogmatic beliefs. They discovered that experiments conducted in 1930s determined that particles larger than 100 microns sank quickly to the floor (rather a different number than 5 microns).

Research published in 1962 demonstrated that rabbits exposed to airborne tuberculosis particles smaller than 5 microns got ill, but those exposed to larger TB particles did not. (This isn’t the case with many other pathogens, however.)

Eventually, their detective work concluded that, in the earliest years of the US Centers for Disease Control, experts conflated and confused matters. 5 microns became a fixation. This was the particle size public health officials erroneously came to believe sank quickly. It also apparently became a mental cut-off between infectious and non-infectious exposure.

Over time, writes journalist Molteni, “through blind repetition, the error sank deeper into the medical canon.” In other words, the medical community’s understanding of how respiratory infections spread has been significantly flawed for much of the past century. On the upside, this story demonstrates that a persistent group of dissidents can sometimes overturn a long-held scientific consensus.

Molteni reports that, due to the efforts of individuals such as Marr, three weeks ago “the WHO quietly updated a page on its website…the text now states that the virus can spread via aerosols as well as larger droplets.”

Which brings us to the second report. Appearing in the New York Times under the headline Why Did It Take So Long to Accept the Facts About Covid? writer Zeynep Tufekci contributes some crucial analysis. She points out that this change on the WHO’s website “didn’t get a lot of attention. There was no news conference, no big announcement.” In her view, that’s a problem. She calls this the opposite of credible leadership.

The WHO, she points out, is responsible for much of the misery we’ve endured over the past year:

If the importance of aerosol transmission had been accepted early, we would have been told from the beginning that it was much safer outdoors, where these small particles disperse more easily, as long as you avoid close, prolonged contact with others. We would have tried to make sure indoor spaces were well ventilated, with air filtered as necessary. Instead of blanket rules on gatherings, we would have targeted conditions that can produce superspreading events: people in poorly ventilated indoor spaces, especially if engaged over time in activities that increase aerosol production, like shouting and singing… [bold added]

COVID databases describe thousands of indoor superspreader events, but Tufekci says she isn’t aware of a single “confirmed outdoor-only case of superspreading.”

One of the most traumatic aspects of the past year has been the suspension of our normal mourning rituals. Whether the departed died of COVID-19 or some other cause, attendance at even outdoor funeral services has been severely restricted. Outdoor events of all sorts have been banned. Police have hassled people for taking country walks, and for sitting in parks and on beaches. During a stressful time, it’s no trivial matter to declare safe, wholesome activities off limits for billions of people.

It’s great that the WHO has finally seen the light. By why has it been so grudging – so surreptitious – about this important correction? In Tufekci’s words:

Righting this ship cannot be a quiet process – updating a web page here, saying the right thing there. The proclamations we now know are wrong were so persistent and so loud for so long.

.

Read the Wired feature story here. Read the NYT analysis here.

via Big Picture News, Informed Analysis

https://ift.tt/34alp0O

May 24, 2021