If the United States Centers for Disease Control and Prevention (CDC) guidelines aren’t enough to convince you that face shields alone shouldn’t be used to stop the spread of COVID-19, then maybe a new visualization study will.

To increase public awareness about the effectiveness of face shields alone as well as face masks with exhalation valves, researchers from Florida Atlantic University’s College of Engineering and Computer Science used qualitative visualizations to test how face shields and masks with valves perform in impeding the spread of aerosol-sized droplets. Widespread public use of these alternatives to regular masks could potentially have an adverse effect on mitigation efforts.

For the study, just published in the journal Physics of Fluids, researchers employed flow visualization in a laboratory setting using a laser light sheet and a mixture of distilled water and glycerin to generate the synthetic fog that made up the content of a cough-jet. They visualized droplets expelled from a mannequin’s mouth while simulating coughing and sneezing. By placing a plastic face shield and an N95-rated face mask with a valve, they were able to map out the paths of droplets and demonstrate how they performed.

Results of the study show that although face shields block the initial forward motion of the jet, the expelled droplets move around the visor with relative ease and spread out over a large area depending on light ambient disturbances. Visualizations for the face mask equipped with an exhalation port indicate that a large number of droplets pass through the exhale valve unfiltered, which significantly reduces its effectiveness as a means of source control.

“From this latest study, we were able to observe that face shields are able to block the initial forward motion of the exhaled jet, however, aerosolized droplets expelled with the jet are able to move around the visor with relative ease,” said Manhar Dhanak, Ph.D., department chair, professor, and director of SeaTech, who co-authored the paper with Siddhartha Verma, Ph.D., lead author and an assistant professor; and John Frankenfeld, a technical professional, all within FAU’s Department of Ocean and Mechanical Engineering. “Over time, these droplets can disperse over a wide area in both lateral and longitudinal directions, albeit with decreasing droplet concentration.”

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University of Arizona and Non-profit Covid Watch Launch COVID-19 Exposure App that Notifies Others Anonymously

University of Arizona students, faculty and staff can now download and opt in to the Covid Watch exposure notification smartphone app, which allows users who have been diagnosed with COVID-19 to anonymously notify others who may have been exposed. After a successful pilot, the goal is for the app to be used statewide.

“The app is a vital part of our [Test-Trace-Treat] plan to mitigate the risk of COVID-19 as we return to campus over the coming weeks with our on-ramp approach,” said University of Arizona President Robbins C. Robbins, MD. “I am very proud of our partnership with Covid Watch, which allows us to prioritize privacy while using this incredible technology for exposure alerts. I hope our entire campus community takes advantage of this resource. The more people who use it, the safer we will be.”

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The Centers for Disease Control and Prevention (CDC) says: “People who have tested positive for COVID-19 do not need to quarantine or get tested again for up to 3 months as long as they do not develop symptoms again.”

The CDC’s current guidance suggests that “People who develop symptoms again within 3 months of their first bout of COVID-19 may need to be tested again if there is no other cause identified for their symptoms.”

A saliva-based laboratory diagnostic test developed by researchers at the Yale School of Public Health has been granted an emergency use authorization by FDA.

“This is a huge step forward to make testing more accessible,” said Chantal Vogels, a Yale postdoctoral fellow, who led the laboratory development and validation along with Doug Brackney, an adjunct assistant clinical professor. “This started off as an idea in our lab soon after we found saliva to be a promising sample type of the detection of SARS-CoV-2, and now it has the potential to be used on a large scale to help protect public health. We are delighted to make this contribution to the fight against coronavirus.” The preprint on the development and validation of SalivaDirect was recently posted on medRxiv.

A Stanford study shows that in severely ill COVID-19 patients, “first-responder” immune cells, which should react immediately to signs of viruses or bacteria in the body, instead respond sluggishly.

Now, a study by investigators at the Stanford University School of Medicine and other institutions has turned up immunological deviations and lapses that appear to spell the difference between severe and mild cases of COVID-19.

That difference may stem from how our evolutionarily ancient innate immune system responds to SARS-CoV-2, the virus that causes the disease. Found in all creatures from fruit flies to humans, the innate immune system rapidly senses viruses and other pathogens. As soon as it does, it launches an immediate though somewhat indiscriminate attack on them. It also mobilizes more precisely targeted, but slower-to-get-moving, “sharpshooter” cells belonging to a different branch of the body’s pathogen-defense forces, the adaptive immune system.

Rochester Institute of Technology (RIT) will test wastewater in residence halls and on-campus apartments twice weekly to detect infections before symptoms show.

“We’re looking for viral RNA, pieces of the virus that get shed off of people when they go to the bathroom,” said Jennifer Schneider, the Eugene H. Fram Chair of Applied Critical Thinking and a professor in the Department of Civil Engineering Technology, Environmental Management and Safety. “By testing wastewater, we can get an idea of what the relative viral prevalence could be in the population using areas of campus. If we see it increase in a particular area, we can look more closely and run some strategic testing.”

Members of RIT’s fall planning task forces say the wastewater surveillance will be a critical and proactive complement to more standard COVID-19 tests like the PCR tests involving nasal swabs. If health officials see spikes in coronavirus levels, they could take actions such as having the residents of the affected areas get further testing.

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New research from several studies in Spain indicate that Covid-19 is causing a wide range of disorders in the nervous system and may be directly attacking the brain

The SARS-CoV-2 coronavirus attacks the respiratory system, but there is growing evidence that it also affects the nervous system. Several studies based on thousands of Spanish patients show that most of these individuals developed at least one neurological problem. This manifested itself in a wide range of symptoms, ranging from headaches to comatose states. In a percentage of cases, neurological conditions were even the principal cause of death. Although these symptoms have been attributed to the body’s excessive immune response to Covid-19, some research indicates that the virus is directly attacking the brain.

The Spanish Neurology Association (SEN) has collated the most recent studies carried out in Spain on the connection between the coronavirus, the brain and the entire nervous system. The research is varied; it includes investigations on how the virus changes a person’s sense of smell and taste, research on headaches in infected healthcare workers, and a study into strokes in 1,600 patients with Covid-19.

But the most significant piece of research is a registry called Albacovid, which studies the neurological conditions observed in 841 coronavirus patients in two hospitals in Albacete in the Spanish region of Castilla-La Mancha during the peak of the crisis in March. The results, published in the specialist journal Neurology a few weeks ago, show that 57% of these patients developed one or several neurological symptoms.

Researchers King’s College London identify 6 different types of coronavirus with increasing severity levels

Six distinct types of coronavirus have been identified by scientists in a breakthrough that promises to save lives by flagging the highest-risk patients. Analysis of thousands of cases by artificial intelligence software has revealed different “clusters” of symptoms and ranked them in order of severity. Each type was found to be distinguished by a particular cluster of symptoms. Moreover, the team found that these types differed in the severity of the disease and the need for respiratory support during hospitalization.

For example, patients with the sixth type of Covid-19 are nearly 10 times more likely to end up needing breathing support than patients in the first group. This is significant because often patients only deteriorate to a critical stage several days after showing symptoms.

The new ranking system could have major implications for clinical management of COVID-19, and could help doctors predict who is most at risk, who is likely to need hospital care in a second wave of coronavirus infections, and give doctors the opportunity to intervene earlier in the highest-risk cases.