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COVID-19 Researchers Identify Features of a Virus Super-Spreader – SciTechDaily

COVID-19 Researchers Identify Features of a Virus Super-Spreader - SciTechDaily
Sneeze Velocity

Sneeze velocity for four different nose and mouth types is shown. A) is open nasal passage with teeth, B) is open nasal passage without teeth, C) is blocked nasal passage without teeth, and D) is blocked nasal passage with teeth. Credit: University of Central Florida

Sneezes from people who have congested noses and a full set of teeth travel about 60% farther than from people who don’t, according to a new study.

New research from the University of Central Florida has identified physiological features that could make people super-spreaders of viruses such as COVID-19.

In a study appearing this month in the journal Physics of Fluids, researchers in UCF’s Department of Mechanical and Aerospace Engineering used computer-generated models to numerically simulate sneezes in different types of people and determine associations between people’s physiological features and how far their sneeze droplets travel and linger in the air.

They found that people’s features, like a stopped-up nose or a full set of teeth, could increase their potential to spread viruses by affecting how far droplets travel when they sneeze.

According to the U.S. Centers for Disease Control and Prevention, the main way people are infected by the virus that causes COVID-19 is through exposure to respiratory droplets, such as from sneezes and coughs that are carrying infectious virus.

Knowing more about factors affecting how far these droplets travel can inform efforts to control their spread, says Michael Kinzel, an assistant professor with UCF’s Department of Mechanical Engineering and study co-author.

“This is the first study that aims to understand the underlying ‘why’ of how far sneezes travel,” Kinzel says. “We show that the human body has influencers, such as a complex duct system associated with the nasal flow that actually disrupts the jet from your mouth and prevents it from dispersing droplets far distances.”

For instance, when people have a clear nose, such as from blowing it into a tissue, the speed and distance sneeze droplets travel decrease, according to the study.

This is because a clear nose provides a path in addition to the mouth for the sneeze to exit. But when people’s noses are congested, the area that the sneeze can exit is restricted, thus causing sneeze droplets expelled from the mouth to increase in velocity.

Similarly, teeth also restrict the sneeze’s exit area and cause droplets to increase in velocity.

“Teeth create a narrowing effect in the jet that makes it stronger and more turbulent,” Kinzel says. “They actually appear to drive transmission. So, if you see someone without teeth, you can actually expect a weaker jet from the sneeze from them.”

To perform the study, the researchers used 3D modeling and numerical simulations to recreate four mouth and nose types: a person with teeth and a clear nose; a person with no teeth and a clear nose; a person with no teeth and a congested nose; and a person with teeth and a congested nose.

When they simulated sneezes in the different models, they found that the spray distance of droplets expelled when a person has a congested nose and a full set of teeth is about 60 percent greater than when they do not.

The results indicate that when someone keeps their nose clear, such as by blowing it into a tissue, that they could be reducing the distance their germs travel.

The researchers also simulated three types of saliva: thin, medium, and thick.

They found that thinner saliva resulted in sneezes comprised of smaller droplets, which created a spray and stayed in the air longer than medium and thick saliva.

For instance, three seconds after a sneeze, when thick saliva was reaching the ground and thus diminishing its threat, the thinner saliva was still floating in the air as a potential disease transmitter.

The work ties back to the researchers’ project to create a COVID-19 cough drop that would give people thicker saliva to reduce the distance droplets from a sneeze or cough would travel, and thus decrease disease-transmission likelihood.

The findings yield novel insight into variability of exposure distance and indicate how physiological factors affect transmissibility rates, says Kareem Ahmed, an associate professor in UCF’s Department of Mechanical and Aerospace Engineering and study co-author.

“The results show exposure levels are highly dependent on the fluid dynamics that can vary depending on several human features,” Ahmed says. “Such features may be underlying factors driving superspreading events in the COVID-19 pandemic.”

The researchers say they hope to move the work toward clinical studies next to compare their simulation findings with those from real people from varied backgrounds.

Study co-authors were Douglas Fontes, a postdoctoral researcher with the Florida Space Institute and the study’s lead author, and Jonathan Reyes, a postdoctoral researcher in UCF’s Department of Mechanical and Aerospace Engineering.

Fontes says to advance the findings of the study, the research team wants to investigate the interactions between gas flow, mucus film and tissue structures within the upper respiratory tract during respiratory events.

“Numerical models and experimental techniques should work side by side to provide accurate predictions of the primary breakup inside the upper respiratory tract during those events,” he says.

“This research potentially will provide information for more accurate safety measures and solutions to reduce pathogen transmission, giving better conditions to deal with the usual diseases or with pandemics in the future,” he says.

Reference: “A study of fluid dynamics and human physiology factors driving droplet dispersion from a human sneeze” by D. Fontes, J. Reyes, K. Ahmed and M. Kinzel, 12 November 2020, Physics of Fluids.
DOI: 10.1063/5.0032006

The work was funded by the National Science Foundation.

Kinzel received his doctorate in aerospace engineering from Pennsylvania State University and joined UCF in 2018. In addition to being a member of UCF’s Department of Mechanical and Aerospace engineering, a part of UCF’s College of Engineering and Computer Science, he also works with UCF’s Center for Advanced Turbomachinery and Energy Research.

Ahmed is an associate professor in UCF’s Department of Mechanical and Aerospace Engineering, a faculty member of the Center for Advanced Turbomachinery and Energy Research, and the Florida Center for Advanced Aero-Propulsion. He served more than three years as a senior aero/thermo engineer at Pratt & Whitney military engines working on advanced engine programs and technologies. He also served as a faculty member at Old Dominion University and Florida State University. At UCF, he is leading research in propulsion and energy with applications for power generation and gas-turbine engines, propulsion-jet engines, hypersonics and fire safety, as well as research related to supernova science and COVID-19 transmission control. He earned his doctoral degree in mechanical engineering from the State University of New York at Buffalo. He is an American Institute of Aeronautics and Astronautics associate fellow and a U.S. Air Force Research Laboratory and Office of Naval Research faculty fellow.

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Tracking COVID-19 in Alaska: 2 deaths and 656 new cases reported Saturday – Anchorage Daily News

Tracking COVID-19 in Alaska: 2 deaths and 656 new cases reported Saturday - Anchorage Daily News
We’re making this important information about the pandemic available without a subscription as a public service. But we depend on reader support to do this work. Please consider joining others in supporting independent journalism in Alaska for just $3.23 a week.

In total, 120 Alaskans and a nonresident have died with COVID-19 since the pandemic began here in March. The two deaths reported Saturday involved an Anchorage woman in her 70s and an Anchorage woman over 80, according to the state health department.

Saturday’s COVID-19 numbers represent a continuation of high case counts statewide that have grown for weeks alongside a nationwide virus surge. Concern surrounding the state’s strained hospital and health care system continues to grow as daily tallies climb.

And health officials say that daily counts may be underreporting new case numbers as lags in data entry persist. They say looking at trends, such as two-week averages, may give a fuller picture of the state’s current virus situation. Almost every region in the state is now in a high-alert level based on the average number of cases per 100,00 people over the last 14 days, with that number steeply rising in multiple regions over the past week. That means there’s widespread community transmission, frequent outbreaks and many undetected cases across Alaska.

People in Alaska are largely getting the virus from friends, family members and co-workers, according to health officials, and many people who tested positive reported going to social gatherings, community events, church services and social venues while they were contagious but did not yet know they had COVID-19.

Officials recommend that Alaskans stay away from gatherings with people they don’t live with and avoid crowds, and they continue to encourage people to stay 6 feet from others and wear masks around non-household members.

As of Saturday, 141 people were currently hospitalized with COVID-19 and another 12 hospital patients were suspected of being infected with the virus. Close to a fifth of all hospital patients statewide had COVID-19 by the weekend. Hospitalizations are rising and the limited availability of staffing is a significant concern, health officials said this week.

Of the 639 new cases reported by the state Saturday among Alaska residents, 262 were in Anchorage, plus 16 in Chugiak, 13 in Eagle River and one in Girdwood; 91 in Wasilla, 29 in Palmer, two in Big Lake, one in Houston and one in Sutton-Alpine; 16 in Soldotna, 12 in Kenai, four in Sterling, two in Seward, two in Homer, one in Fritz Creek and one in Nikiski; 37 in Fairbanks and seven in North Pole; 11 in Kodiak; 10 in Nome; seven in Utqiagvik; seven in Juneau; seven in Sitka; six in Bethel; three in Delta Junction; three in Kotzebue; two in Dillingham; two in Chevak; one in Ketchikan; one in Petersburg; and one in Unalaska.

Among communities smaller than 1,000 people not named to protect privacy, there were 55 resident cases in the Bethel Census Area; eight in the Kusilvak Census Area; four in the northern Kenai Peninsula Borough; four in the Yukon-Koyukuk Census Area; two in the Northwest Arctic Borough; two in the North Slope Borough; one in the Kodiak Island Borough; one in the Valdez-Cordova Census Area; one in the Denali Borough; one in the Prince of Wales-Hyder Census Area; and one in the Yakutat plus Hoonah-Angoon region.

Seventeen cases were reported among nonresidents: seven in Anchorage, two in Delta Junction, one in Fairbanks, one in Wasilla, one in the Southeast Fairbanks Census Area and five in unidentified regions of the state.

The percentage of positive cases among people arriving in Alaska is five times what it was just weeks ago, at around 5%, officials said in a weekly report. Traveling by air risks exposure in airports, on planes, in taxis or rideshares and after arriving, they said.

While people might get tested more than once, each case reported by the state health department represents only one person.

Among the new cases, it is not reported how many people were showing symptoms when they tested positive. The Centers for Disease Control and Prevention estimates that about a third of people who have the virus are asymptomatic.

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Should you quarantine after Thanksgiving gathering amid rising COVID cases? Yes, expert says – WPVI-TV

Should you quarantine after Thanksgiving gathering amid rising COVID cases? Yes, expert says - WPVI-TV
Thanksgiving is over. Many people celebrated with just their household unit, but many others did not. In fact, up to 50 million Americans are traveling over the Thanksgiving weekend, according to the American Automobile Association, or AAA.

The comings and goings of US travelers belie the fact that the COVID-19 pandemic continues to surge. The US reported 2,046 deaths Wednesday — the highest one-day coronavirus death toll the country has reported since early May, Johns Hopkins University data shows. The country also hit a new daily hospitalization record, with 89,954 people currently hospitalized for COVID-19, according to the COVID Tracking Project. This is the 16th straight day that figure set a record for the pandemic, as previously reported by CNN.

We talked to CNN Medical Analyst Dr. Leana Wen about her recommendations on how to keep safe after people return from holiday festivities.

First and foremost, anyone who traveled to visit with family and friends or hosted guests outside their immediate household unit should quarantine, Wen advised.

Taking action to protect others around you will help mitigate the spread of COVID-19, especially with Hanukkah, Christmas and New Year’s just around the corner.

CNN: Many people took a risk and got together with loved ones for Thanksgiving. Why are you recommending that these people quarantine after they return?

Dr. Leana Wen: Coronavirus is surging all across the country, and there are hotspots in so many areas. Anyone who traveled to another part of the country and got together with other people could be at risk for contracting COVID-19. When they return to their home communities, they could spread it – to people in their households and to friends, colleagues and any other people around them.

We are facing an impending calamity. Many hospitals are already at the brink. ICUs are full. We all need to do our part and flatten the curve again. And that means knowing when we are at risk to others around us. If you’ve traveled, and have seen other people, you could pose a risk to your community.

CNN: How should you go about assessing your risk?

Wen: There are three things you should consider when assessing your own risk exposure. First, consider who you saw over the holidays. How many guests were there and what were their risks? If you visited elderly parents who have been quarantining themselves, that’s very low risk to you. On the other hand, if you were together with three households, some with teenage children who are in school, and they’ve been at work themselves, and these households haven’t been quarantining, the risk is much higher.

Second, what activities did you do with others? If you only saw people outdoors, spaced at least 6 feet apart, the risk is very low. Time spent indoors is high risk, particularly if you are in poorly ventilated spaces for long periods of time, and where people are eating and drinking (and therefore don’t have masks on). If you stayed in someone’s house, the risk could be even higher, because the time of exposure was longer.

Third, what kind of exposure did you have during travel? If you drove, the risk will be lower than if you flew. I’m actually less concerned about your risk exposure during the flight than all the other components, like waiting at the airport and boarding the jetway, where there’s the potential of people crowding together in less well-ventilated spaces. If you wore a three-ply surgical mask the whole time, that further reduces risk. Overall, I’m most concerned about the risks of getting together with people.

CNN: What does a quarantine look like?

Wen: Good question. By quarantine, I mean that you should act as if you’ve been exposed to someone with coronavirus, because you could have. That means you should not be around others as much as possible. Do not go into work. Keep kids out of school. Get groceries delivered. Definitely do not get together with others during this period.

The safest thing to do is to quarantine for 14 days. If you have testing readily available, you could quarantine for at least seven days after the date of return and then get tested.

I recognize that this is asking a lot. For some people, this full protocol may not be necessary, if your risk during travel was truly very low (that is, if you saw elderly parents only who were already quarantined and you drove yourself). But if you got together with others who have risk themselves, know that you are now at risk, too.

Please keep in mind just how contagious COVID-19 is, and that nearly 60% of the spread is by people who don’t have symptoms. I am certain that none of us want to inadvertently infect others and increase the level of community spread where we live.

CNN: The community I’m going back to is a hotspot itself. Should I still quarantine?

Wen: Yes. Just because the area you’re going back to also has a lot of COVID-19 doesn’t mean that you don’t have a responsibility to try to keep the level from getting higher. Having hospitals overwhelmed affects all of us – not just patients with coronavirus but also patients with cancer and heart disease who may not be able to get the care they need.

CNN: What if you have roommates who didn’t travel with you?

Wen: If you normally live at home with other people who didn’t go with you on your travels, you should stay away from them during your quarantine period. Do not spend time in shared spaces. If this can’t be avoided – for example, if you have a shared restroom or kitchen – wear a mask, open the windows and do not use either space at the same time as others. Remember that they could have risk themselves if they traveled too, so please urge them also to follow the same quarantine protocol.

CNN: What should you do if you are staying put, for example, if you’re a college student and school has let out?

Wen: For some students, they were able to quarantine and then get tested prior to returning home. In that case, they are fine to see their family members – though they must continue to be vigilant and not engage in risky behaviors like seeing their friends indoors. For those who couldn’t, they should quarantine once they return home, following the same procedures as above: ideally 14 days and if not, at least seven days and then take a test.

CNN: Will I need to follow all these procedures for Christmas and New Year’s, too?

Wen: Yes. There will almost certainly be an even higher level of coronavirus infection by then, and hospitals will be in an even more dire position. I highly encourage everyone to put off nonessential travel. We are so close to getting a vaccine that will allow us to see one another safely again. Please, let’s get through this winter. Keep up the safeguards that we know to work: Wear a mask. Practice physical distancing. Do not gather indoors. I know it’s very hard, but we can make it through this winter!

The-CNN-Wire ™ & © 2020 Cable News Network, Inc., a WarnerMedia Company. All rights reserved.

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Illinois COVID-19 Updates: Tom Dart Tests Positive, State Reports More Than 7,800 New Cases – NBC Chicago

Illinois COVID-19 Updates: Tom Dart Tests Positive, State Reports More Than 7,800 New Cases - NBC Chicago

Note: Any news conferences from Gov. J.B. Pritzker, Chicago Mayor Lori Lightfoot or other officials will be streamed in the video player above.

Here are the latest coronavirus headlines from around the state of Illinois.

Cook County Sheriff Thomas Dart Tests Positive for COVID-19

Cook County Sheriff Thomas Dart has tested positive for coronavirus and is quarantining at his home, officials announced Saturday.

According to the Cook County Sheriff’s Office, Dart was tested for the virus on Tuesday and received his positive test results on Friday.

The sheriff was last in the office on Nov. 19. He began to feel symptoms of the virus on Friday and immediately self-quarantined.

Illinois Officials Report 7,873 New COVID-19 Cases, 108 Additional Deaths

The Illinois Department of Public Health reported 7,873 confirmed and probable cases of coronavirus on Saturday, along with 108 additional deaths attributed to the virus.

According to the latest figures released by the department, the state has now reported 712,936 total cases of the virus since the pandemic began, along with 12,137 fatalities.

The state performed an additional 79,055 tests over the last 24 hours, giving the state a total of 10,368,278 tests performed during the pandemic.

Deck the Halls? Not at the Illinois Capitol Due to COVID-19

The coronavirus has extinguished some traditional holiday cheer at the Illinois Capitol.

There will be no Christmas tree nor any holiday displays inside or outside the building, The State Journal-Register reported.

The Capitol for months has been closed to all but employees and others with permission. Tours were suspended months ago because of the COVID-19 pandemic.

Lights on the Capitol dome won’t be used for the second consecutive year. Engineers have recommended that an observation deck, which is typically used to anchor the lights, should be fortified.

Saturday’s Ohio State-Illinois Game Postponed Due to Positive COVID-19 Tests

The University of Illinois’ home football game against the Ohio State Buckeyes has been postponed after a series of positive COVID-19 test results within the Ohio State program.

The school made the official announcement Friday night, cancelling the Saturday morning game between the two schools that was set to be played at Champaign’s Memorial Stadium.

The announcement came after a second round of coronavirus testing of the Ohio State roster on Friday. The school said that it had seen an increased number of positive COVID-19 tests earlier Friday, with head coach Ryan Day among those who tested positive for the illness.

Chicagoland Christmas Trees Selling Fast Amid Pandemic Restrictions

The coronavirus pandemic has made Christmas tree hunting a bit different this year, but that hasn’t stopped families from making sure to get their trees in time for the holiday season.

Some Christmas tree farms in Illinois are requiring reservations, due to the pandemic, and as of Friday afternoon, many times were already sold out for the weekend.

The early and high demand for trees comes during an ongoing Christmas tree shortage across the country. According to experts, this shortage has its roots (pun intended) in the 2008 global recession, which led to a slowdown in planting seedlings.

It can take a tree 7 to 20 years to reach the desired height, so business owners can’t flood the market overnight, no matter how high the demand is.

Farmers are now raising their prices on Christmas trees, which could be passed down to the consumer.

Illinois COVID Metrics: A Region-by-Region Look at the State’s Latest Coronavirus Data

All 11 of Illinois’ healthcare regions are currently operating under Tier 3 coronavirus mitigation rules, but some regions are trending in the right direction to have those rules eased in the coming weeks.

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Illinois health officials report 7,873 COVID-19 cases, 108 deaths – WGN TV Chicago

Illinois health officials report 7,873 COVID-19 cases, 108 deaths - WGN TV Chicago

CHICAGO Illinois health officials announced 7,873 new confirmed and probable cases of COVID-19 Saturday, including 108 additional deaths Saturday as public health experts fear recent progress in mitigation was lost over Thanksgiving.

The deaths were reported in the following counties:

  • Bureau County: 1 female 80s
  • Cook County: 1 female 30s, 3 females 40s, 2 males 40s, 3 males 50s, 6 females 60s, 9 males 60s, 10 females 70s, 10 males 70s, 12 females 80s, 11 males 80s, 5 females 90s, 3 males 90s
  • DuPage County: 1 male 50s, 1 female 60s, 2 males 70s, 1 male 80s, 2 males 90s
  • Greene County: 1 female 60s
  • Knox County: 1 male 70s
  • Lake County: 1 male 70s, 1 male 80s
  • Macoupin County: 1 male 70s
  • Madison County: 2 females 60s, 1 female 70s, 1 female 80s, 2 females 90s, 2 males 90s
  • Ogle County: 1 female 90s
  • Peoria County: 1 female 70s, 1 female 80s
  • St. Clair County: 1 male 90s
  • Stephenson County: 1 male 60s
  • Whiteside County: 2 males 60s, 1 female 80s, 1 female 90s
  • Will County: 1 female 40s, 1 female 70s
  • Williamson County: 1 male 80s

Currently, IDPH is reporting a total of 712,936 cases, including 12,137 deaths, in 102 counties in Illinois.

Within the past 24 hours, laboratories have reported 79,055 specimens for a total of 10,368,278.

As of Friday night, 5,775 people in Illinois were reported to be hospitalized with COVID-19. Of those, 1,211 patients were in the ICU and 686 patients were on ventilators.

The preliminary seven-day statewide positivity for cases as a percent of total tests from November 21 to November 27 is 10.1%. The preliminary seven-day statewide test positivity from November 21 to November 27 is 12.2%.

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COVID-19 in South Dakota: 819 total new cases; Death toll rises to 942; Active cases at 17,106 –

COVID-19 in South Dakota: 819 total new cases; Death toll rises to 942; Active cases at 17,106 -

PIERRE, S.D. (KELO) — A record number of COVID-19 deaths were reported on Saturday as South Dakota surpassed more than 900 deaths due to the virus, according to the update from the state department of health.

Fifty-four new COVID-19 deaths were reported, bringing the total to 942. There have been 527 deaths reported since Nov. 1. The new deaths were 23 women and 31 men listed in the following age ranges: 80+ (25); 70-79 (13); 60-69 (11); and 50-59 (5). The new deaths were listed in the following counties: Aurora (2), Beadle (1), Brown (1), Buffalo (2), Charles Mix (1), Codington (4), Davison (4), Day (2), Faulk (2), Grant (1), Gregory (1), Hamlin (1), Hanson (1), Hutchinson (1), Jackson (2), Lincoln (2), Minnehaha (11), Oglala Lakota (2), Pennington (4), Roberts (2), Tripp (2), Turner (2), Union (2) and Walworth (1).

On Saturday, 819 new total coronavirus cases were reported bringing the state’s total case count to 79,099, up from Friday (78,280). Total recovered cases are now at 61,051, up from Friday (61,010).

Active cases increased to 17,106 from Friday (16,382).

Current hospitalizations are at 539, down from Friday (569). Total hospitalized are now at 4,400, up from Friday (4,353).

Total persons tested negative is now at 246,277, up from Friday (245,204).

There were 1,892 new persons tested reported on Saturday. The new person test positivity rate for Saturday is 43-percent.

The latest 7-day all test positivity rate, reported by the DOH, is 13.8%. The DOH calculates that based on the results of the PCR test results but doesn’t release total numbers for how many PCR tests are done daily. The DOH 1-day PCR test positivity rate is reported at 12.8%.

Only four of South Dakota’s 66 counties are not listed as having “substantial” community spread.

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