This website uses cookies to ensure you get the best experience on our website. Learn more

Covid-19: How the Virus Gets in and How to Block It: Aerosols, Droplets, Masks, Face Shields, & More

x

Covid-19: How the Virus Gets in and How to Block It: Aerosols, Droplets, Masks, Face Shields, & More

In this Covid-19 Medical Grand Rounds (July 16, 2020), three world experts discuss a variety of issues surrounding how the coronavirus moves from person to person, how best to block viral spread, and the potential that mask-wearing may not only prevent infection but also lead to a milder clinical course. The questions regarding aerosol vs. droplet transmission and the value of wearing masks and/or face shields are central to formulating public health strategies as well as to informing the personal decisions that each of us makes every day. The session is hosted by UCSF Department of Medicine chair Bob Wachter.

Program
Bob Wachter: Introduction
00:04:45 – Aerosol vs. Droplets:
Don Milton, Professor, Environmental & Occupational Health, University of Maryland School of Public Health
00:25:35 – Q&A
00:29:03 – Masks:
Monica Gandhi, UCSF Professor of Medicine; Associate Chief of Division of HIV, Infectious Diseases, and Global Medicine at ZSFG; Director of the UCSF Center for AIDS Research; and Medical Director of the HIV Clinic, Ward 86, ZSFG
00:45:46 – Q&A
00:48:25 – Face Shields:
Michael Edmond, Chief Quality Officer and Associate Chief Medical Officer, University of Iowa Health Care; Professor of Medicine, Division of Infectious Diseases, University of Iowa Carver College of Medicine
01:06:14 – Q&A
01:08:10 – Panel Discussion
01:28:57 – Bob Wachter: Closing

See previous Covid-19 Medical Grand Rounds:
• July 9: The State of the Pandemic, Opening the Schools, and the Outbreak at San Quentin State Prison

• June 25: Special Presentation: An Interview with John Barry, Author of the Bestselling Book, The Great Influenza: The Story of the Deadliest Pandemic in History

• June 18: Covid-19: Update in Therapies (including Steroids), and Covid Patients with Persistent Symptoms: What’s Going On?

• June 11: Covid-19: Update in Epidemiology, and, Are the Publication and FDA Approval Processes Moving Too Fast for Safety?


See all UCSF Covid-19 grand rounds, which have been viewed more than 300,000 times, here:
x

How Effective Against Coronavirus Are Face Shields Compared To Masks? | TODAY

As summer temperatures soar, face shields present a tempting alternative to masks to prevent the spread of coronavirus, and they cover your eyes as well as your mouth and nose. NBC investigative and consumer correspondent Vicky Nguyen reports as TODAY’s Search for Solutions series continues.
» Subscribe to TODAY:
» Watch the latest from TODAY:

About: TODAY brings you the latest headlines and expert tips on money, health and parenting. We wake up every morning to give you and your family all you need to start your day. If it matters to you, it matters to us. We are in the people business. Subscribe to our channel for exclusive TODAY archival footage & our original web series.

Connect with TODAY Online!
Visit TODAY's Website:
Find TODAY on Facebook:
Follow TODAY on Twitter:
Follow TODAY on Instagram:
Follow TODAY on Pinterest:

#FaceShields #Coronavirus #TodayShow

How Effective Against Coronavirus Are Face Shields Compared To Masks? | TODAY
x

High speed camera captures how different types of face masks work

Which mask works best? To visualise droplets and aerosols, UNSW researchers used LED lighting system & a high-speed camera, filming people coughing and sneezing in different scenarios — using no mask, 2 different types of cloth masks, and a surgical mask.

We confirmed that even speaking generates substantial droplets. Coughing and sneezing (in that order) generate even more.

A three-ply surgical mask was significantly better than a one-layered cloth mask at reducing droplet emissions caused by speaking, coughing and sneezing, followed by a double-layer cloth face covering.

A single-layer cloth face covering also reduced the droplet spread caused by speaking, coughing and sneezing but was not as good as a two-layered cloth mask or surgical mask.

We do not know how this translates to infection risk, which will depend on how many asymptomatic or mildly symptomatic infected people are around. However, it shows a single layer is not as good a barrier as a double layer.

Here's more on what we found:

VIDEO: UNSW/ Thorax
AUTHORS:
- C Raina MacIntyre, Professor of Global Biosecurity, NHMRC Principal Research Fellow, Head, Biosecurity Program, Kirby Institute, UNSW;
- Abrar Ahmad Chughtai, Epidemiologist, UNSW;
- Charitha de Silva, Lecturer, UNSW;
- Con Doolan, Professor, School of Mechanical and Manufacturing Engineering, UNSW;
- Prateek Bahl, PhD Candidate, School of Mechanical and Manufacturing Engineering, UNSW, and;
- Shovon Bhattacharjee, PhD Candidate, The Kirby Institute, UNSW

For more videos like this subscribe to our channel:

We're the official channel of UNSW Sydney, a brilliantly located university between the coast and the city.
x

Face shields vs. face masks: Does one offer better protection from COVID-19?

Local 4's Dr. McGeorge explains how face shields differ from face masks when it comes to preventing the spread of the coronavirus (COVID-19).
x

Inexpensive way to test face mask effectiveness in reducing COVID-19 transmission

Dr. Martin Fischer, Ph.D., from Duke University, developed a simple, low-cost technique to visualize the effectiveness of different face coverings on droplet emissions during normal wear. Testing several face coverings, the researchers found that the particles can be blocked by some, but not all recommended face coverings. N95s without valves, and surgical, and polypropylene masks worked best. Cotton face coverings provided some coverage. Bandanas and neck fleece didn’t block the droplets very much.

COVID-19 | Clear Face Shields

While traditional face masks are critical to stopping the spread of COVID-19, they can pose some unique challenges for healthcare workers and some patients. We've partnered with UW-Madison College of Engineering to help design and test prototypes of clear face masks that not only make communication easier but also provide a greater sense of connection.

Learn more:

COVID-19 Update 16: Effectiveness of surgical masks for prevention

In this video, we further touch on the distinction between droplets and aerosols. The WHO and others claim that COVID-19 is primarily spread by the inhalation of aerosols and near range droplets. There are others who disagree with this statement, and so there is confusion on if masks are helpful or not. To support this claim, we review a study in which viral load in the air was measured in various public locations. Finally, we take a look at a recent trial demonstrating that simple surgical masks worn by individuals with upper respiratory tract infections could significantly reduce viral concentration in the exhaled air.

#medmastery #coronavirus #COVID19 #sarscov2 #coronaviruschina #coronavirustruth #coronavirusdeaths #WHO #wuhan #infection #pandemic #publichealth
-------------------------------------------------
Links for reference:









-----------------------------------------------------------
More updates by Dr. Wiesbauer:
COVID-19 Update 1: How to tell if a pandemic is likely to occur or not–R0 and the serial interval:
COVID-19 Update 2: How to stop an epidemic - Herd immunity:
COVID-19 Update 3: Symptoms of COVID-19:
COVID-19 Update 4: Clinical characteristics of COVID-19:
COVID-19 Update 5: Estimating case fatality rates for COVID-19:
COVID-19 Update 6: Seasonality: will COVID-19 go away in the summer?:
COVID-19 Update 7: This is probably the most important picture of the whole Coronavirus-epidemic:
COVID-19 Update 8: Zinc and chloroquine for the treatment of COVID-19?:
COVID-19 Update 9: Hydroxychloroquine and azithromycin for the treatment of COVID-19–Review of study by Didier Raoult:
COVID-19 Update 10: Is COVID-19 an airborne disease? Will we all need to wear face-masks against SARS-CoV-2?
COVID-19 Update 11: How exactly the coronavirus becomes airborne.
COVID-19 Update 12: Attack rates of COVID-19 depend on face-to-face time spent with infected persons:

COVID-19 Update 13: Randomized Controlled Trial of Hydroxychloroquine in Patients with COVID-19:

COVID-19 Update 14: Are children contributing to the spread of COVID-19?

COVID-19 Update 15: Can we disinfect and reuse N95 masks?:
-----------------------------------------------------------
Useful resources:
For checking daily developments of cases, deaths and more:



Other useful resources:
Journal Watch:

New England Journal of Medicine:

Github collaboration:

CDC:

WHO:

Nucleuswealth:

-------
Speaker: Franz Wiesbauer, MD MPH
Internist & Founder at Medmastery
LinkedIn:
PubMed:

Check out our course library and register for a free trial account:

Facebook:
Twitter:

Please Note: Medmastery's videos, medical lectures, medical illustrations, and medical animations are for medical education and exam preparation purposes, and not intended to replace recommendations by your doctor or health care provider.

See how masks stop the spread of COVID-19 - Nebraska Medicine

How does a mask prevent respiratory droplets from spreading? Using laser light scattering, researchers visualized droplets when someone is masked or unmasked.

The New England Journal of Medicine published the video in an article called Visualizing Speech-Generated Oral Fluid Droplets via Laser Light Scattering.

Read the article at:

Face shields don't protect against COVID: Explained

A Japanese study has indicated that face shields alone are not effective enough in preventing COVID-19 infection. Here is all you need to know.

#FaceShield #COVID19 #JapaneseStudy #VortexRings #Sneeze #Droplets #Virus #ViralParticles #Plastic #PlasticPollution

..............................................................................................
NEWS9 is widely known to be the undisputed leader and most trusted source of news and information in Karnataka. Today, NEWS9 is the fastest growing digital news platform in India. NEWS9 brings you thought-provoking stories from across the Globe on topics ranging from Politics, Finance, Entertainment & Sports to latest trends on Social media, Lifestyle, Tech and Wellness.


► Watch us on YouTube :
► Like us on Facebook :
► Follow us on Instagram :
► Follow us on Twitter :

#NEWS9 #NEWS9live #NEWS9india #NEWS9bengaluru #breakingnews
#topnews #livenews #bignews #NEWS9karnataka #latestnews #latesttrends #news

New findings warn of higher risk in airborne coronavirus transmissions | COVID-19 Special

What does the latest research tell us about the spread of coronavirus? Do masks help prevent new infections?
A study by Berlin's Charite Hospital has found the risk of catching the coronavirus from contaminated surfaces is lower than thought. The bad news is the risk from droplets and aerosols is greater than previously thought. Aerosols are tiny particles, like fine dust. Virus particles can attach themselves to the aeorsols and spread infection. While larger droplets can't travel far because they fall to the ground, smaller aerosols are lighter and float in the air for several hours indoors, spreading all over. Scientists are now certain that these are the main infection route indoors. That means talking, singing, coughing or sneezing can spread the virus when inside.
Subscribe:

For more news go to:
Follow DW on social media:
►Facebook:
►Twitter:
►Instagram:
Für Videos in deutscher Sprache besuchen Sie:
#Coronavirus #Aerosols #Droplets
x

Aerosols vs. Droplets: In Transmitting COVID-19, There’s a Big Difference

When COVID-19 first began to spread, health officials were initially concerned with the transmission of droplets. These larger particles from the mouths of infected people generally travel less than six feet, hence the social distancing rule of people staying six feet away from each other.

But in July, 239 scientists signed a letter to the World Health Organization stating that they believe that aerosol particles - particles much smaller than droplets that can stay in the air for hours - are also responsible for the transmission of the disease. Jordan Peccia, the Thomas E. Golden, Jr. Professor of Chemical & Environmental Engineering, was among those among those who signed the letter. In the video, Peccia details the differences between droplets and aerosols, and the ways we can protect ourselves from both.

Everything you need to know about face masks | COVID-19 Special

How useful are face masks during the coronavirus crisis? Experts can’t really agree on this: Should we wear them? And if so: who should wear them? Do they protect me, or the other person? And which types of masks make sense at all?
In many Asian countries, face masks are regarded as one of the main weapons in the fight against the coronavirus. And in China it’s even forbidden to be on the streets without a mask.
Here in Europe, we have mixed feelings about wearing masks. In times of scarcity many believe masks should be reserved for healthcare workers who depend on protection. But that view seems to have changed recently. Now more and more local authorities do recommend to wear masks in public.
So let's talk about face masks - and what they can do for us during a pandemic.Subscribe:

For more news go to:
Follow DW on social media:
►Facebook:
►Twitter:
►Instagram:
Für Videos in deutscher Sprache besuchen Sie:
#Coronavirus #Covid19 #FaceMasks

COVID 10: Is COVID-19 an airborne disease? Will we all need to wear face-masks against SARS-CoV-2?

There seems to be a lot of confusion in the droplet versus aerosol discussion and how these relate to the spread of COVID-19. Is it airborne and inhaled or droplet based via fomites and hands? The uncomfortable truth is that we have evidence for both modes.

In this video we first define what a droplet and an aerosol is based on their behaviour in the environment. We then examine both through the findings from two published studies. We will also discuss how long viral particles survive and stay viable and able to infect after they fall on a surface or get suspended in the air.

For COVID-19, we agree that the various transmission routes may predominate in different settings. The airborne route is relevant for hospitals and hospital staff as well as crowded and badly ventilated public spaces. Everyone else is more likely to get the virus through touching surfaces, bad hand hygiene and then touching their face.

#medmastery #coronavirus #COVID19 #sarscov2 #coronaviruschina #coronavirustruth #coronavirusdeaths #WHO #wuhan #infection #pandemic #publichealth
-----------------------------------------------------------
Links for reference:




-----------------------------------------------------------
More updates by Dr. Wiesbauer:
COVID-19 Update 1: How to tell if a pandemic is likely to occur or not–R0 and the serial interval:
COVID-19 Update 2: How to stop an epidemic - Herd immunity:
COVID-19 Update 3: Symptoms of COVID-19:
COVID-19 Update 4: Clinical characteristics of COVID-19:
COVID-19 Update 5: Estimating case fatality rates for COVID-19:
COVID-19 Update 6: Seasonality: will COVID-19 go away in the summer?:
COVID-19 Update 7: This is probably the most important picture of the whole Coronavirus-epidemic:
COVID-19 Update 8: Zinc and chloroquine for the treatment of COVID-19?:
COVID-19 Update 9: Hydroxychloroquine and azithromycin for the treatment of COVID-19–Review of study by Didier Raoult:
-----------------------------------------------------------
Useful resources:
For checking daily developments of cases, deaths and more:



Other useful resources:
Journal Watch:

New England Journal of Medicine:

Github collaboration:

CDC:

WHO:

Nucleuswealth:

-------
Speaker: Franz Wiesbauer, MD MPH
Internist & Founder at Medmastery
LinkedIn:
PubMed:

Check out our course library and register for a free trial account:

Facebook:
Twitter:

Please Note: Medmastery's videos, medical lectures, medical illustrations, and medical animations are for medical education and exam preparation purposes, and not intended to replace recommendations by your doctor or health care provider.

Covid Face Masks | Best + Worst Face Masks For Covid-19 Prevention | Dr. William Li

Most and least effective face masks to protect against Covid-19 ranked, including N95 masks, surgical masks + cloth masks — according to a doctor.

How Scientists Test Face Mask Effectiveness Against Coronavirus | NBC Nightly News

Scientists around the world have conducted research that finds wearing face masks can significantly decrease the spread of the coronavirus by blocking droplets created when a person coughs, sneezes, or talks that would carry the virus.» Subscribe to NBC News:
» Watch more NBC video:

NBC News is a leading source of global news and information. Here you will find clips from NBC Nightly News, Meet The Press, and original digital videos. Subscribe to our channel for news stories, technology, politics, health, entertainment, science, business, and exclusive NBC investigations.

Connect with NBC News Online!
Visit NBCNews.Com:
Find NBC News on Facebook:
Follow NBC News on Twitter:
Follow NBC News on Instagram:

How Scientists Test Face Mask Effectiveness Against Coronavirus | NBC Nightly News
x

Pandemic science, Wear a mask to protect yourself

All referenced hyperlinked below for personal perusal and verification. CDC



Masks reduce the spray of droplets when worn over the nose and mouth

Prevent people who have COVID-19 from spreading virus to others

Respiratory virus shedding in exhaled breath and efficacy of face masks (Nature Medicine)



Aerosol transmission is a potential mode of transmission for coronaviruses as well as influenza viruses and rhinoviruses

Universal use of face masks for success against COVID-19: evidence and implications for prevention policies (European Respiratory Journal)



Cloth masks are a simple, economic and sustainable alternative to surgical masks as a means of source control of SARS-CoV-2 in the general community

Mask wearers are dramatically less likely to get a severe case of Covid-19



Professor Monica Gandhi, San Francisco General Hospital.

No mask is perfect

Wearing one might not prevent you from getting infected

But it might be the difference between a case of Covid-19 that sends you to the hospital and a case so mild you don’t even realize you’re infected.

Masks Do More Than Protect Others During COVID-19: Reducing the Inoculum of SARS-CoV-2 to Protect the Wearer (Journal of General Internal Medicine)



Universal masking reduces the “inoculum”

Leading to more mild and asymptomatic infection manifestations

Masks, depending on type, filter out the majority of viral particles, but not all

Viral inoculum and severity of disease (LD50)

Rising rates of asymptomatic infection with population-level masking

Increased with mask wearing, decreased where few masks are worn

So, more asymptomatic infections

Greater community-level immunity and slower spread


Cloth Masks May Prevent Transmission of COVID-19: An Evidence-Based, Risk-Based Approach (Annals of Internal Medicine)




The point is not that some particles can penetrate but that some particles are stopped

Every virus-laden particle retained in a mask is not available to hang in the air as an aerosol or fall to a surface to be later picked up by touch.

Cloth can block droplets and aerosols, and layers add efficiency.

Immunity and immunopathology to viruses: what decides the outcome? (Nature, Reviews Immunology)



The outcome of host–viral interactions depend on

Dose and route of infection

Viral virulence properties

Several host factors that mainly involve innate and adaptive immunity

If the exposure dose is very high, the immune response can become overwhelmed.

If the initial dose of the virus is small, the immune system is able to contain the virus with less drastic measures.

If this happens, fewer symptoms, if any

A simple method of estimating fifty per cent end points, (American Journal of Hygiene, 1938)



Viral dose being related to disease severity

Validation of the Wild-type Influenza A Human Challenge Model H1N1pdMIST: An A(H1N1)pdm09 Dose-Finding Investigational New Drug Study (Clinical Infectious Diseases)



Clinical symptoms of influenza occurred at all doses (Table 1), but were most prevalent at 106 and 107 TCID (tissue culture infectious dose)

Higher viral doses, the more sick people became

Simple Respiratory Protection—Evaluation of the Filtration Performance of Cloth Masks and Common Fabric Materials Against 20–1000 nm Size Particles, (The Annals of Occupational Hygiene)



Masks increase the rate of asymptomatic cases, (Annals of Internal Medicine)







COVID-19: in the footsteps of Ernest Shackleton, (MBJ, Thorax)



Cases at seafood plant cause spike in Oregon COVID numbers (Pacific Seafoods)



Releases Covid-19 Test Results at Northwest Arkansas Facilities (Tyson)

Droplets and Aerosols generated by singing & the risk of COVID-19 for choirs.

Prateek Bahl, Charitha de Silva, Shovon Bhattacharjee, Haley Stone, Con Doolan, Abrar Ahmad Chughtai, C Raina MacIntyre


For more videos like this subscribe to our channel:

We're the official channel of UNSW Sydney, a brilliantly located university between the coast and the city.

Universal Face Shields: A Better Option for COVID-19 Containment?

Contagion Editorial Director Allie Ward speaks with Michael B. Edmond, MD, MPH, MPA, MBA, associate chief medical officer, University of Iowa Health Care, about a viewpoint published in JAMA, which hypothesized that universally adopting face shields could help cut the transmissibility of COVID-19.

How to make a face shield in 2 minutes & DIY Fluid resistant cover for N95: 14 min Pep talk for HCW

Hi everyone, this is the “MacGyver” version for making the face shield when you don't have a hot glue gun. The original version uses a hot glue gun from Michaels instead of the Scotch tape. Posted on My Instagram account @georgeyangmd

To convert an existing or damaged face shield to a reusable one with discardable cushion and head band:

0:00 How to make face shields
9:32 How to make Omega face mask, using Non-woven fluid resistant fabric found in the hospital as a N95 Cover, to conserve the medical face masks as separate use PPE.

I believe that the hospitals, city, and state governments are all trying to procure PPE for our front line healthcare professionals. The problem is that since the federal government has not taken over by federal mandate to take all of the inventory, to ration and distribute them by need, some hospitals are better stocked, while others are are running out. New York Governor Cuomo said that they had a large order for N95 PPE which evaporated, because they were outbid by another purchaser. Private citizens and groups are all trying to help, and may purchase the PPE at a premium to ensure that they are getting them for distribution for their website or Kickstarter supporters, but who knows if the competition between all of the purchasers is actually making some confirmed orders disappear into thin air. If the New York State government can have an order disappear, what may happen with a smaller funded hospital. It's not an excuse, but I don't think this is being done intentionally. This started in Wuhan China, and much of the PPE manufacturing is in China. Closures of their factories immediately compromised the supply chain.

So what can we do? We need to think outside of the box and purchase items that other people are not thinking of. The raw materials. Acetate sheeting or vinyl sheeting, foam cushion, and braided elastic. Stores like Michael's (Arts and Crafts), Joann's (fabric), or Staples have supplies which can make a face shield which work to block splashes and sprays towards the face. If they can't ship them quickly enough we can buy the less in demand raw materials and fashion #MacGyver our own face shields until they can provide more.

I chose the face shields because I can't make N95 masks without significant technology and special materials. In addition N95 masks depend on fit testing to make sure there is no leakages of the N95 mask. A simpler solution is to protect and keep the N95 filter surface as clean as possible to make sure the filtering ability remains viable and doesn't clog making it difficult to breath, as well as protecting them from getting dirty with visible splashes of bodily fluids and droplets. Face shields seem like the obvious first piece of protection between the patient's mouth and the HCW mouth. My hospital is recommending to add a procedural mask on top of the N95 when performing procedures which may result in droplets or aerosol. Procedural masks are usually fluid resistant.

In the second part of the Video 9:32, I describe the Omega Face mask (HCW version) which uses fluid resistant materials we find readily in a healthcare environment (gowns, drapes, autoclave paper wraps, cold pack sleeves). These materials are usually baby blue in color which identifies them. Since elective surgeries are cancelled and most of the Covid-19 care is not surgically related, these surgical gowns and drapes might be used to make many fluid resistant face masks to protect the N95 and extending their usefulness.

If you watched Dr. David Price's Viral video interview with his family members, he said that he only wore the N95 mask when performing procedures which would result in aerosol production. Otherwise, he would wear a surgical mask when not in those situations. This will also prolong the effectiveness of the N95 masks. He seemed confident that the mode of transmission through Human to human contact is from a contaminated hand to mouth/nose/eye area. He felt it was possible from breathing in an aerosol breathed out from an infectious patient, but if you kept a 6 foot distance the risk is still lower. The main benefit of a non-N95 mask is really to ensure that your hands do not touch your nose and mouth area accidentally. We are creatures of habit and also human, so even if you are really good 95-99% of the time, only wearing the mask when outside 100% of the time and washing your hands religiously immediately after touching a potentially contaminated surface (so you don't forget to do it, if think you will wash it later when you get home.)

Hope that makes sense. Good luck, be safe. Follow the rules 100%.

DOCTOR REVEALS TRUTH ABOUT MASKS: Why Healthcare Workers Are Catching COVID-19

Why are 10% of COVID-19 (coronavirus) cases health care workers? Are we not protecting ourselves well enough? We’re going to tackle this question head on and I've asked Dr. Rishi Desai, the former epidemic intelligence officer for the CDC, pediatric infectious disease doctor and current medical director at Osmosis, to give us his opinion.

What the difference between a surgical mask and N95?
Is coronavirus spread by droplet or aerosols?

For those of you who are new here, I'm Siobhan, a 3rd year internal medicine resident working on the front lines of the coronavirus pandemic in Canada.

HUGE thank you to Dr. Desai for sharing his thoughts with us!
Check out this link to see a the Osmosis COVID page to see more videos by Dr. Desai and a free trial of Osmosis:

SUBSCRIBE so you never miss a video
COMMENT with any questions or just to say hi
LIKE if you want to see more like this!

See you in the next video!
~ Siobhan (Violin MD) ~
--------------------------------------------------
❤ YOU MAY ALSO ENJOY WATCHING... ❤

Doctor Explains Coronavirus:


26 hour call shift in ICU with Code Blue


26 hour call shift with 2 code blues


Doctor Shadows an ICU Nurse

-------------------------------------------------
???? REFERENCES:


Shares

x

Check Also

x

Menu