Monday, May 23, 2022
No Result
View All Result
Medical Finance
  • Home
  • News
  • Interviews
  • Mediknowledge
  • Insights From Industry
  • Thought Leaders
  • Coronavirus
  • Whitepapers
  • Home
  • News
  • Interviews
  • Mediknowledge
  • Insights From Industry
  • Thought Leaders
  • Coronavirus
  • Whitepapers
No Result
View All Result
Medical Finance
No Result
View All Result
Home News

Respiratory virus particles likely travel greater distance than previously thought

by Medical Finance
in News
New evidence supports the link between growth-induced respiratory stress and fish reproduction
9
SHARES
99
VIEWS
Share on FacebookShare on Twitter

A modeling study raises questions about how far respiratory droplets, like those that transmit the virus that causes COVID-19, can travel before becoming harmless. Can the airborne particles that carry the virus remain infectious not just for a few feet but rather more than 200 feet, farther than the length of a hockey rink?

Experiments dating to the 1930s proposed two paths for respiratory droplets like those from a sneeze or cough. Either they are big and heavy, plummeting to the ground without much chance of infecting another person. Or they are so small and light that they dry out almost instantly, remaining airborne but becoming harmless very quickly. The dryness renders “enveloped” viruses like coronaviruses unable to infect.

But a new study from scientists at the Department of Energy’s Pacific Northwest National Laboratory suggests a third option-;that small respiratory particles can remain moist and airborne for a longer time and greater distance than scientists have recognized.

There are reports of people becoming infected with a coronavirus downwind of an infected person or in a room several minutes after an infected person has exited that room.”


Leonard Pease, corresponding author of the study

The findings were published in the February issue of the journal International Communications in Heat and Mass Transfer.

“The idea that enveloped virions may remain well hydrated and thus fully infective at substantial distances is consistent with real-world observations. Perhaps infectious respiratory droplets persist longer than we have realized,” Pease added.

The PNNL team took a long look at the mucus that coats the respiratory droplets that people spew from their lungs. Scientists know that mucus allows many viruses to travel further than they otherwise would, enabling them to journey from one person to another.

Conventional wisdom has been that very small, aerosolized droplets of just a few microns, like those produced in the lungs, dry out in air almost instantly, becoming harmless. But the PNNL team found that mucus changes the equation.

The team found that the mucus shell that surrounds respiratory droplets likely reduces the evaporation rate, increasing the time that viral particles within the droplets are kept moist. Since enveloped viruses like SARS-CoV-2 have a fatty coating that must be kept moist for the virus to be infectious, the slower evaporation allows viral particles to be infectious longer.

The team estimates that droplets encased in mucus could remain moist for up to 30 minutes and travel up to about 200 feet.

“While there have been many factors proposed as variables in how COVID spreads,” said Pease, “mucus remains largely overlooked.”

Authors of the paper include Pease and Nora Wang Esram, Gourihar Kulkarni, Julia Flaherty and Carolyn Burns.

Viral journeys between offices

The focus on mucus helps address another question: how the virus moves in a multiroom office building.

Hitching a ride within respiratory droplets is the first step for the virus to become airborne and infect those who breathe it in. Chemist Carolyn Burns had the task of creating artificial, respiratory-like droplets to study how the particles moved from room to room.

Ultimately, Burns settled on two substances to carry artificial virus-like particles. One was bovine mucus; the other was sodium alginate, a compound derived from brown seaweed. The compound is commonly used as a thickening agent in foods like ice cream and cheese.

The team used an airbrush to disperse droplets in one room of a multiroom laboratory building. Together, the droplets and airbrush simulated a person’s coughing fit, releasing particles for about one minute in a source room. A team led by Alex Vlachokostas and Burns measured droplet levels in two adjoining rooms with controlled building ventilation.

The team’s experimental findings, published Jan. 19 in Indoor Air, echo the findings of its previous modeling study, published last year in the journal Building and Environment.

The scientists found that both low and high levels of filtering were effective at reducing levels of respiratory droplets in all rooms. Filtration quickly cut down the levels of droplets in the adjoining rooms-;within about three hours, to one-third the level or less without filtration.

The team also found that increasing ventilation rapidly reduced particle levels in the source room. But particle levels in the other connected rooms jumped immediately; levels spiked 20 to 45 minutes later with vigorous air changes increasing the spike. Ultimately, after the initial spike, levels of droplets in all the rooms gradually dropped after three hours with filtration and after five hours without it.

The scientists say that increased air exchange for crowded spaces may be beneficial in certain situations, like large conferences or school assemblies, but in normal work and school conditions, it may actually increase transmission rates throughout all rooms of a building.

“If you’re in a downstream room and you’re not the source of the virus, you probably are not better off with more ventilation,” said Pease.

Source:

Pacific Northwest National Laboratory

Journal reference:

Pease, L.F., et al. (2022) A missing layer in COVID-19 studies: Transmission of enveloped viruses in mucus-rich droplets. International Communications in Heat and Mass Transfer. doi.org/10.1016/j.icheatmasstransfer.2021.105746.

Total
0
Shares
Share 0
Tweet 0
Pin it 0
Share 0
Medical Finance

Medical Finance

Related Posts

Potential new diagnostic marker predicts successful, efficient development of mammalian egg cells

Potential new diagnostic marker predicts successful, efficient development of mammalian egg cells

by Medical Finance
May 23, 2022
0

Researchers at the Centre for Genomic Regulation (CRG) in Barcelona have identified a potential new diagnostic marker that predicts the...

Study hints a potential difference in molecular clockworks between the master and slave clock neurons

Study hints a potential difference in molecular clockworks between the master and slave clock neurons

by Medical Finance
May 23, 2022
0

From tiny fruit flies to human beings, all animals on Earth maintain their daily rhythms based on their internal circadian...

Bacterial biofilms use a developmental patterning mechanism seen in plants and animals

Biologists reveal structure of newly discovered speargun-like molecular injection systems in bacteria

by Medical Finance
May 23, 2022
0

Biologists from ETH Zurich have discovered speargun-​like molecular injection systems in two types of bacteria and have described their structure...

Study identifies cellular receptors for alphaviruses shared across mosquitoes, humans, and animals

Human nose organoids provide better understanding of the first steps toward SARS-CoV-2 infection

by Medical Finance
May 23, 2022
0

Preclinical models that recapitulate aspects of human airway disease are essential for the advancement of novel therapeutics and vaccines. In...

New mathematical model can calculate the risk of resistance evolution for drug pairs

Estonian Microbiome Project demonstrates the impact of long-term antibiotic use on the microbiome

by Medical Finance
May 23, 2022
0

Estonian Microbiome Project, using electronic health data from more than 2500 biobank participants finds long-term antibiotic usage, independent from recent...

Scientists unravel how blood cells mount the first line of defense against viruses

YME1L protein regulates the production of new nerve cells in the brain

by Medical Finance
May 23, 2022
0

Researchers at the University of Cologne have discovered that the protein YME1L regulates the production of new nerve cells and...

Next Post
What are the benefits of Irish Life Sciences’ new 2.2 mL square well ‘V’ bottom plate?

Combating infectious diseases with reagent banks

New research may help better understand the causes of human diseases

0 0 votes
Article Rating
Subscribe
Login
Notify of
guest
guest
0 Comments
Inline Feedbacks
View all comments

Support

  • Contact
  • Disclaimer
  • Home
  • Privacy Policy
  • Terms And Conditions

Categories

  • Coronavirus
  • Insights From Industry
  • Interviews
  • Mediknowledge
  • News
  • Thought Leaders
  • Whitepapers

More News

  • Study: Third primary SARS-CoV-2 prophylactic mRNA vaccines enhances antibody responses in the majority of patients with haematological malignancies: Results from the MARCH study. Image Credit: Chinnapong/Shutterstock
    Third dose of messenger RNA vaccines found to increase serological immunity in hematological malignancy patients
  • Study: Guillain-Barré syndrome and SARS-COV2 coronavirus. Vaccinate or get infected with COVID? What poses less risk? Image Credit: Bangkok Click Studio / Shutterstock
    Bibliographic review evaluates risk of Guillain-Barré syndrome after receiving COVID vaccination
  • Home
  • Privacy Policy
  • Contact
  • Disclaimer
  • Terms And Conditions

© 2022 Medical Finance - Latest Financial and Business News

No Result
View All Result
  • Interviews
  • Mediknowledge
  • News
  • Insights From Industry
  • Coronavirus
  • Thought Leaders
  • Whitepapers
wpDiscuz
0
0
Would love your thoughts, please comment.x
()
x
| Reply