Researchers make case for airborne spread of COVID-19; virus may travel through tiny particles
(KWTX) - An international team of researchers is making a case for airborne spread of the new coronavirus through tiny beads of moisture that humans expel when they sing, talk or breathe.
The 239 scientists from around the world signed a July 6 letter that says the virus may spread from person to person through “micoroplets” too small to see with the naked eye.
“We appeal to the medical community and to the relevant national and international bodies to recognize the potential for airborne spread of COVID-19. There is significant potential for inhalation exposure to viruses in microscopic respiratory droplets…at short to medium distances…and we are advocating for the use of preventive measures to mitigate this route of airborne transmission,” the team said in the letter.
Six faculty members of the University of Colorado in Boulder including chemistry Professor Jose-Luis Jimenez say the pathogen behind the virus likely can drift through the air, especially in crowded indoor spaces such as bars and restaurants.
"Once droplets carrying the virus become small enough, they can stay in the air for minutes or even hours, and we can breathe them in during that time if we are in the same room," Jimenez said.
"You have to help the disease by being indoors for a long time without masks on and in crowded conditions, and with low ventilation. Shouting or singing also helps," Jimenez said.
"It's similar to what we've seen happening in bars and restaurants in places like Texas."
After a post-Memorial Day surge in the number of COVID-19 cases in Texas, Gov. Greg Abbott issued an executive order on June 26 shutting down bars, scaling back restaurant dining, and closing rafting and tubing outfitters on popular rivers as COVID-19 cases soar in the state.
Restaurants, which had been operating at 75% capacity, were ordered to scale back to 50%.
The order also banned, gatherings of more than 100 people with certain exceptions, unless a mayor of county judge grants approval.
Businesses must continue to operate at 50% occupancy.
CU environmental engineering Professor Shelly Miller also signed the letter.
"More than 200 scientists from different disciplines and from around the world read our letter, and overwhelmingly agreed to sign on," she said.
"That's a powerful statement."
On Thursday, three days after the letter was published, the World Health Organization updated its guidance on the spread of the virus, acknowledging outbreaks linked to such closed settings as restaurants, nightclubs, churches and workplaces and issuing an urgent call for further investigation.
Research, the professors say, also suggests ventilation is an important factor in transmission of the virus.
Outside airflow could clear the droplets from the air inside.
"We need as much outside air as possible," Miller said.
"If you have to recirculate air, then use the highest rated filter that you can."
But regardless of how the virus spreads, individual precautions do make a difference.
"I hope the general public can understand that this is isn't about politics or taking away your freedoms," Miller said.
“It’s about giving you the freedom to be able to go out and eat at a restaurant and shop and do what you love doing, but in a healthy way.”
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