Many ventilation systems may increase risk of COVID-19 exposure, study suggests

UNIVERSITY OF CAMBRIDGE

Research News

 

Ventilation systems in many modern office buildings, which are designed to keep temperatures comfortable and increase energy efficiency, may increase the risk of exposure to the coronavirus, particularly during the coming winter, according to research published in the Journal of Fluid Mechanics.

A team from the University of Cambridge found that widely-used 'mixing ventilation' systems, which are designed to keep conditions uniform in all parts of the room, disperse airborne contaminants evenly throughout the space. These contaminants may include droplets and aerosols, potentially containing viruses.

The research has highlighted the importance of good ventilation and mask-wearing in keeping the contaminant concentration to a minimum level and hence mitigating the risk of transmission of SARS-CoV-2, the virus that causes COVID-19.

The evidence increasingly indicates that the virus is spread primarily through larger droplets and smaller aerosols, which are expelled when we cough, sneeze, laugh, talk or breathe. In addition, the data available so far indicate that indoor transmission is far more common than outdoor transmission, which is likely due to increased exposure times and decreased dispersion rates for droplets and aerosols.

"As winter approaches in the northern hemisphere and people start spending more time inside, understanding the role of ventilation is critical to estimating the risk of contracting the virus and helping slow its spread," said Professor Paul Linden from Cambridge's Department of Applied Mathematics and Theoretical Physics (DAMTP), who led the research.

"While direct monitoring of droplets and aerosols in indoor spaces is difficult, we exhale carbon dioxide that can easily be measured and used as an indicator of the risk of infection. Small respiratory aerosols containing the virus are transported along with the carbon dioxide produced by breathing, and are carried around a room by ventilation flows. Insufficient ventilation can lead to high carbon dioxide concentration, which in turn could increase the risk of exposure to the virus."

The team showed that airflow in rooms is complex and depends on the placement of vents, windows and doors, and on convective flows generated by heat emitted by people and equipment in a building. Other variables, such as people moving or talking, doors opening or closing, or changes in outdoor conditions for naturally ventilated buildings, affect these flows and consequently influence the risk of exposure to the virus.

Ventilation, whether driven by wind or heat generated within the building or by mechanical systems, works in one of two main modes. Mixing ventilation is the most common, where vents are placed to keep the air in a space well mixed so that temperature and contaminant concentrations are kept uniform throughout the space.

The second mode, displacement ventilation, has vents placed at the bottom and the top of a room, creating a cooler lower zone and a warmer upper zone, and warm air is extracted through the top part of the room. As our exhaled breath is also warm, most of it accumulates in the upper zone. Provided the interface between the zones is high enough, contaminated air can be extracted by the ventilation system rather than breathed in by someone else. The study suggests that when designed properly, displacement ventilation could reduce the risk of mixing and cross-contamination of breath, thereby mitigating the risk of exposure.

As climate change has accelerated since the middle of the last century, buildings have been built with energy efficiency in mind. Along with improved construction standards, this has led to buildings that are more airtight and more comfortable for the occupants. In the past few years however, reducing indoor air pollution levels has become the primary concern for designers of ventilation systems.

"These two concerns are related, but different, and there is tension between them, which has been highlighted during the pandemic," said Dr Rajesh Bhagat, also from DAMTP. "Maximising ventilation, while at the same time keeping temperatures at a comfortable level without excessive energy consumption is a difficult balance to strike."

In light of this, the Cambridge researchers took some of their earlier work on ventilation for efficiency and reinterpreted it for air quality, in order to determine the effects of ventilation on the distribution of airborne contaminants in a space.

"In order to model how the coronavirus or similar viruses spread indoors, you need to know where people's breath goes when they exhale, and how that changes depending on ventilation," said Linden. "Using these data, we can estimate the risk of catching the virus while indoors."

The researchers explored a range of different modes of exhalation: nasal breathing, speaking and laughing, each both with and without a mask. By imaging the heat associated with the exhaled breath, they could see how it moves through the space in each case. If the person was moving around the room, the distribution of exhaled breath was markedly different as it became captured in their wake.

"You can see the change in temperature and density when someone breathes out warm air - it refracts the light and you can measure it," said Bhagat. "When sitting still, humans give off heat, and since hot air rises, when you exhale, the breath rises and accumulates near the ceiling."

Their results show that room flows are turbulent and can change dramatically depending on the movement of the occupants, the type of ventilation, the opening and closing of doors and, for naturally ventilated spaces, changes in outdoor conditions.

The researchers found that masks are effective at reducing the spread of exhaled breath, and therefore droplets.

"One thing we could clearly see is that one of the ways that masks work is by stopping the breath's momentum," said Linden. "While pretty much all masks will have a certain amount of leakage through the top and sides, it doesn't matter that much, because slowing the momentum of any exhaled contaminants reduces the chance of any direct exchange of aerosols and droplets as the breath remains in the body's thermal plume and is carried upwards towards the ceiling. Additionally, masks stop larger droplets, and a three-layered mask decreases the amount of those contaminants that are recirculated through the room by ventilation."

The researchers found that laughing, in particular, creates a large disturbance, suggesting that if an infected person without a mask was laughing indoors, it would greatly increase the risk of transmission.

"Keep windows open and wear a mask appears to be the best advice," said Linden. "Clearly that's less of a problem in the summer months, but it's a cause for concern in the winter months."

The team are now working with the Department for Transport looking at the impacts of ventilation on aerosol transport in trains and with the Department for Education to assess risks in schools this coming winter.

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Reference:

Rajesh K. Bhagat et al. 'Effects of ventilation on the indoor spread of COVID-19.' Journal of Fluid Mechanics (2020). DOI: 10.1017/jfm.2020.720.

Study shows heating in vaping device as cause for lung injury

Nicotine, THC or Vitamin E oil may not be the primary factor in e-cig or vaping product use-associated lung injury (EVALI)

UNIVERSITY OF CALIFORNIA - IRVINE

Research News

 

Irvine and Pasadena, CA - Sept. 28, 2020 - Early results of an experimental vaping study have shown significant lung injury from E-cigarette (eC) devices with nickel-chromium alloy heating elements. The findings were consistent, with or without the use of nicotine, vitamin E oil or tetrahydrocannabinol (THC), which have previously been thought to contribute to the life-threatening respiratory problem.

The early results, published in the Journal of the American Heart Association by researchers from the University of California, Irvine (UCI) School of Medicine and the Huntington Medical Research Institutes (HMRI), were observed during a larger study designed to explore the effect of e-cigarette and other vaping product use on the cardiovascular system. While conducting experiments, researchers observed eC or vaping product use-associated lung injury (EVALI) immediately after switching from a vaping device with a stainless steel heating element, to one that used nickel-chromium alloy (NC).

"The results were so impactful, we felt it imperative to release the initial findings early so that electronic cigarette users could be cautioned sooner, especially considering E-cigarette users are at increased risk of COVID-19," stated senior author Robert A. Kloner, MD, PhD, chief science officer for HMRI and professor of medicine at USC.

The switch in devices occurred in September 2019, when the eC device the team was using went off market and a substitute device was offered as an alternative. The new device was physically compatible with the original exposure system, but the heating element changed from stainless steel (SS) to a nickel?chromium alloy (NC).

"Within an hour of beginning an experiment, we observed evidence of severe respiratory distress, including labored breathing, wheezing and panting," said Michael Kleinman, PhD, professor of occupational and environmental medicine at UCI School of Medicine and member of the UCI Center for Occupational and Environmental Health. "After analyzing lung tissue from subjects in the study, we found them to be severely compromised and observed other serious changes such as lung lesions, red blood cell congestion, obliteration of alveolar spaces, and pneumonitis in some cases."

The current research aimed to study the impacts of breathing in E-cigarette vapors on heart function in a well- established pre-clinical experimental model. Over the course of nearly a year, none of the subjects exposed to vapors from the stainless steel devices, both with and without additives, contracted respiratory distress and only one showed a less than 10% area of inflammation in the lungs. Once the new eC device was introduced, affected subjects showed severe respiratory distress, with labored breathing, wheezing and panting. The lung injury occurred without nicotine, THC, or Vitamin E additives; and may also have been related to higher wattage of power settings on the E-cigarette devices. These preliminary studies will be followed up with additional future studies to systematically try to determine the cause of the lung problem.

"While further research is needed, these results indicate that specific devices and power settings may play a key role in the development of EVALI as much as the additives do," said Kloner. "The harms associated with E-cigarettes and vaping simply cannot be overstated."

Vaping has been proven to cause increased blood pressure, endothelial dysfunction, and the risk of myocardial infarction and stroke. Heating elements in commercially available eC are usually made of stainless steel, nickel?chromium or nichrome, Kanthal nickel, or titanium.

A condition, which was dubbed "E?cigarette or vaping product use-associated lung injury" (EVALI) was recognized in the United States in June 2019 and peaked in September 2019. In March 2020, there were 2,800 US cases of EVALI and 68 deaths reported. Patients were typically found to be young males and users of E-cigarettes or vaping products whose CT scans revealed lung inflammation and injury. Of note, EVALI can mimic many of the features of COVID-19 pneumonia.

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This study was funded in part by the National Institutes of Health. In addition to Kleinman and Kloner, several researchers participated in the study, including HMRI researchers Jianru Shi, Wangde Dai, Juan Carreno, Jesus Chavez, and Lifu Zhao; and UCI researchers Rebecca Johnson Arechavala, David Herman, Irene Hasen and Amanda Ting.

About HMRI

At HMRI, our scientists and teams are powered by passion and determination, working tirelessly to uncover new and uncharted solutions to some of humankind's most daunting cardiovascular and neurological challenges, like heart disease, Alzheimer's, neurodevelopmental and psychiatric disorders. Established in 1952, HMRI's history is rich with impactful research from significant work on the cerebrospinal fluid shunt system for hydrocephalus to the perfection of MRI spectroscopy for use with brain tumors, dementia, stroke, MS, and cancers. Today, our campus in Pasadena, CA, includes biomedical laboratories focused on the connections between the brain and heart, a MRI for clinical studies, and a Liver Center. Our all glass building was designed intentionally to reflect our mission to be transparent with information between leadership, donors and researchers. We invite those who share our passion to join us. Come see it, have a hand in it: Big-impact, life-changing solutions are happening today at HMRI. For more information visit us at http://www.hmri.org.

About the UCI School of Medicine

Each year, the UCI School of Medicine educates more than 400 medical students, and nearly 150 doctoral and master's students. More than 700 residents and fellows are trained at UCI Medical Center and affiliated institutions. The School of Medicine offers an MD; a dual MD/PhD medical scientist training program; and PhDs and master's degrees in anatomy and neurobiology, biomedical sciences, genetic counseling, epidemiology, environmental health sciences, pathology, pharmacology, physiology and biophysics, and translational sciences. Medical students also may pursue an MD/MBA, an MD/master's in public health, or an MD/master's degree through one of three mission-based programs: the Health Education to Advance Leaders in Integrative Medicine (HEAL-IM), the Leadership Education to Advance Diversity-African, Black and Caribbean (LEAD-ABC), and the Program in Medical Education for the Latino Community (PRIME-LC). The UCI School of Medicine is accredited by the Liaison Committee on Medical Accreditation and ranks among the top 50 nationwide for research. For more information, visit som.uci.edu.

 

Scientists got one step closer to solving a major problem of hydrogen energy

FAR EASTERN FEDERAL UNIVERSITY

Research News

 

IMAGE: FE-NI-MO-B METALLIC GLASS, GRAPHICALL ABSTRACT view more 

CREDIT: FEFU PRESS OFFICE

A team of scientists from Far Eastern Federal University (FEFU) together with their colleagues from Austria, Turkey, Slovakia, Russia (MISIS, MSU), and the UK found a way to hydrogenate thin metallic glass layers at room temperature. This technology can considerably expand the range of cheap, energy-efficient, and high-performance materials and methods that can be used in the field of hydrogen energy. An article about the study was published in the Journal of Power Sources.

The team developed an amorphous nanostructure (FeNi-based metallic glass) that can be used in the field of hydrogen energy to accumulate and store hydrogen, in particular, as a replacement for Li-ion batteries in small-sized systems.

Metallic glass has the potential to replace palladium, an expensive element that is currently used in hydrogen systems. The lack of economically feasible energy storage systems is the main hindrance preventing hydrogen energy from scaling up to the industrial level. With the new development, the team came one step closer to solving this problem.

"Hydrogen is the most common chemical element in the Universe, a source of clean renewable energy that has the potential to replace all types of fuel used today. However, its storage poses a major technological problem. One of the key materials used to store and catalyze hydrogen is palladium. However, it is very expensive and has a low affinity to oxidizing or reducing environments under extreme conditions. These factors prevent hydrogen energy from being used on the industrial level. The problem can be solved with metallic glasses. They are amorphous metals and lack long range atomic order. Compared to crystalline palladium, metallic glasses are much cheaper and more resistant to aggressive environments. Moreover, due to the so-called atomic free volume (i.e. space between atoms), such glasses can 'soak up' hydrogen more effectively than any other materials with crystalline structure," said Yurii Ivanov, an assistant professor of the Department of Computer Systems at the School of Natural Sciences, FEFU.

According to the researcher, metallic glass has enormous potential in the energy industry thanks to its amorphous structure, lack of certain defects that are typical for polycrystalline metals (such as grain boundaries), and high resistance to oxidation and corrosion.

What makes this work unique is the fact that electrochemical methods were used both to hydrogenate metallic glasses and to study their ability to absorb hydrogen. Standard hydrogenation methods (such as gas adsorption) require high temperature and pressure which has a negative effect on the properties of metallic glasses and narrows the range of materials that can be used in the study. Unlike gas adsorption, electrochemical hydrogenation causes hydrogen to react with the surface of an electrode (made of FeNi metallic glass) at room temperature, just like in the case with palladium.

The new method can work as an alternative to the common gas-solid reaction for alloys with low capacity or hydrogen absorption/release speed.

The team also suggested a new concept of 'effective volume' that can be used to analyze the efficiency of hydrogen absorption and release by metallic glasses. To do so, the thickness and composition of the glass-hydrogen reaction area are measured using high-resolution electron microscopy and X-ray photoelectron spectroscopy.

In the future, the team plans to develop and optimize new metallic glass compositions for practical energy applications.

Earlier a team of material scientists from FEFU, Cambridge (UK), and the Chinese Academy of Sciences had developed a method of 'rejuvenation' of 3D metallic glasses that are the most promising for practical use. The glasses had been made more moldable and resistant to above-critical loads. The improved metallic glasses can be used in many fields, from plastic electronics to various sensors and transformer cores, medical implants, and protective coatings of satellites.

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Earthquake lightning: Mysterious luminescence phenomena

SHINSHU UNIVERSITY

Research News

CREDIT: TSUNEAKI YAMABE, FACULTY OF TEXTILE SCIENCE AND ENGINEERING TECHNICAL STAFF. LABORATORY INVESTIGATION OF EARTHQUAKE LIGHTNING DUE TO LANDSLIDE, EARTH, PLANETS AND SPACE (2020) https://www.shinshu-u.ac.jp/english/

Were you aware that earthquakes are sometimes associated with luminescence, called earthquake lightning? This phenomenon had been documented throughout history, such as between 1965 and 1967, the Matsushiro earthquake swarm caused the surrounding mountain to flicker with light multiple times. In 1993 when an earthquake caused a tsunami off the coast in Southwest Hokkaido which caused 5 boats resting at shore to instantly ignite and burn. Various models have been proposed to explain earthquake lightnings, and it seems as though various factors contribute to such light emissions. Professor Emeritus Yuji Enomoto of Shinshu University, first author of the study Laboratory investigation of earthquake lightning due to landslide does not think these incidents can be explained in a unified way using a single model.

           SUPPOSED UFO IS IN FACT VOLCANIC LUMINESCENCE

Therefore, the study focused on luminescence phenomenon caused by landslides. The team picked out various types of rock that form mountains representative of land across Japan; granite, pyroclastic rocks, rhyolite, limestone and serpentinite. What he found was that different rocks have different reasons for luminescence and some rocks such as serpentinite does not emit light at all.

Granite is known to exhibit remarkable photoemission due to the piezo-induced effect of the quartz within. There have been witness accounts of earthquake lightning in areas without granite. The researchers looked at descriptions of earthquake lightning in the Japan Historical Earthquake Archives. At least 5 of the 55 accounts of earthquake lightnings were due to landslides since 869 A.D.

You can probably imagine how light can be emitted when rocks collide violently. However, the luminescence of rocks is instantaneous and faint. For this reason, ultra-sensitive, high-speed, high resolution cameras and spectroscopes were required for the study. Fortunately, excellent cameras with an ISO sensitivity of 25,600 was available in the market at relatively low prices. For ultra-sensitive spectrum analysis, a device suitable for the purpose was commercially available but too expensive. Fortunately, the research team was able to borrow one from Konica Minolta, and the difficulty of continuing research was solved. Please view the attached video to see the method of the experiment, and different visual observations of the types of light emitted.

There are many cases in which electromagnetic anomalies associated with earthquakes have been documented while the cause remains a mystery. Even though it is a rare phenomenon, Professor Emeritus Enomoto feels an obligation as a Geo-tribologist to elucidate such phenomena. He hopes understanding such phenomena will lead to the advancement of earthquake prediction and promote active disaster prevention.

During the 2011 magnitude 9.0 Tohoku-Oki Earthquake, the number of electrons in the ionosphere suddenly increased above the epicenter of the earthquake about 10 minutes after the earthquake struck. Professor Emeritus Enomoto has studied this incident and proposed the lithosphere-hydrosphere-atmosphere-ionosphere coupling model in terms of current generation of charged mists. He is currently working to elucidate why in 1995, during the Hyogo-ken Nanbu Earthquake, the sky in the West which ordinarily remains dark became brighter than usual, and the color changed from bluish purple, white, then red. This is a difficult task. Professor Enomoto hopes to put together a research-outreach book that explains these incidents so that they can be understood by a wider audience.

CRIMINAL CAPITALISM

 The secretive networks used to move money offshore

Researchers have uncovered a highly unusual network pattern within the Panama Papers, showing how fortunes can be easily hidden in secretive offshore shell corporations, and how these remain difficult to trace and take down

UNIVERSITY OF SOUTHERN CALIFORNIA

Research News

 

In 2016, the world's largest ever data leak dubbed "The Panama Papers" exposed a scandal, uncovering a vast global network of people--including celebrities and world leaders, who used offshore tax havens, anonymous transactions through intermediaries and shell corporations to hide their wealth, grow their fortunes and avoid taxes.

Researchers at USC Viterbi School of Engineering have now conducted a deep analysis of the entities and their interrelationships that were originally revealed in the 11.5 million files leaked to the International Consortium of Investigative Journalists. The academic researchers have made some discoveries about how this network and transactions operate, uncovering uniquely fragmented network behavior, vastly different from more traditional social or organizational networks, demonstrating why these systems of transactions and associations are so robust and difficult to infiltrate or take down. The work has been published in Applied Network Science.

Lead author Mayank Kejriwal is an assistant professor working in the Daniel J. Epstein Department of Industrial and Systems Engineering and USC's Information Sciences Institute who studies complex (typically, social) systems like online trafficking markets using computational methods and network science. He said the research team's aim was to study the Panama Papers network as a whole, in the same way you might study a social network like Facebook, to try to understand what the network behavior can tell us about how money can be moved.

"In general, in any social network like LinkedIn or Facebook, there is something called 'Small World Phenomenon', which means that you're only ever around six people away from anyone in the world," Kejriwal said.

"For instance, if you want get from yourself to Bill Gates, on average you would be around six connections away," he said.

However the team discovered that the Panama Papers network was about as far removed from this traditional social or organizational network behavior as it could possibly be. Instead of a network of highly integrated connections, the researchers discovered a series of secretive disconnected fragments, with entities, intermediaries and individuals involved in transactions and corporations exhibiting very few connections with other entities in the system.

"It was really unusual. The degree of fragmentation is something I have never seen before," said Kejriwal. "I'm not aware of any other network that has this kind of fragmentation."

"So (without any documentation or leak), if you wanted to find the chain between one organization and another organization, you would not be able to find it, because the chances are that that there is no chain - it's completely disconnected," Kejriwal said.

Most social, friendship or organizational networks contain a series of triangular structures in a system known as the 'friend of a friend phenomenon."

"The simple notion is that a friend of a friend is also a friend," Kejriwal said. "And we can measure that by counting the number of triangles in the network."

However, the team discovered that this triangular structure was not a feature of the Panama Papers network.

"It turns out that not only is it not prevalent, but it's far less than prevalent than even for a random network," Kejriwal said. "If you literally randomly connect things, in a haphazard fashion and then you count the triangles in that network, this network is even sparser than that." He added, "Compared to a random network, in this type of network, links between financial entities are scrambled until they are essentially meaningless (so that anyone can be transacting with anyone else)."

It is precisely this disconnectedness that makes the system of secret global financial dealings so robust. Because there was no way to trace relationships between entities, the network could not be easily compromised.

"So what this suggests is that secrecy is built into the system and you cannot penetrate it," Kejriwal said.

"In an interconnected world, we don't expect anyone to be impenetrable. Everyone has a weak link," Kejriwal said. "But not in this network. The fact it is so fragmented actually protects them."

Kejriwal said the network behavior demonstrates that those involved in the Panama Papers network of offshore entities and transactions were very sophisticated, knowing exactly how to move money around in a way that it becomes untraceable and they are not vulnerable through their connections to others in the system. Because it is a global network, there are few options for national or international bodies to intervene in order to recoup taxes and investigate corruption and money laundering.

"I don't know how anyone would try to bring this down, and I'm not sure that they would be able to. The system seems unattackable," Kejriwal said.

Puzzled scientists seek reasons behind Africa's low fatality rates from pandemic


By Alexander Winning

JOHANNESBURG (Reuters) - Africa’s overburdened public health systems, dearth of testing facilities and overcrowded slums had experts predicting a disaster when COVID-19 hit the continent in February.

FILE PHOTO: A health worker walks between beds at a temporary field hospital set up by Medecins Sans Frontieres (MSF) during the coronavirus disease (COVID-19) outbreak in Khayelitsha township near Cape Town, South Africa, July 21, 2020. REUTERS/Mike Hutchings

The new coronavirus was already wreaking havoc in wealthy Asian and European nations, and a United Nations agency said in April that, even with social-distancing measures, the virus could kill 300,000 Africans this year.

In May the World Health Organization (WHO) warned that 190,000 people on the continent could die if containment measures failed. Yet as the world marks 1 million COVID-19 deaths, Africa is doing much better than expected, with a lower percentage of deaths than other continents.

The continent’s case fatality count stands at 2.4%, with roughly 35,000 deaths among the more than 1.4 million people reported infected with COVID-19, according to Reuters data as at late Monday. In North America, it is 2.9% and in Europe 4.5%

Hard-hit countries such as Italy and Britain have recorded fatality counts of 11.6% and 9.0% respectively, compared to 1.6% for Ethiopia, 1.9% for Nigeria and 2.4% for South Africa, the continent’s worst affected country.

Hospitals in many African countries say COVID-19 admission rates are falling.

“Based on what we have seen so far it is unlikely that we are going to see anything at the scale that we are seeing in Europe - both in terms of infections and mortality,” said Rashida Ferrand, a London School of Hygiene and Tropical Medicine professor working at the Parirenyatwa Group of Hospitals in the Zimbabwean capital Harare.

Experts say that some COVID-19 deaths in Africa probably are being missed. Testing rates in the continent of about 1.3 billion people are among the lowest in the world, and many deaths of all types go unrecorded.

South Africa saw some 17,000 extra deaths from natural causes between early May and mid-July, 59% more than would normally be expected, according to a July report from the South African Medical Research Council. That suggests the death toll from COVID-19 could be significantly higher than the official figure, currently over 16,000, researchers say. Even so, there is wide agreement that COVID-19 fatality rates have not so far been as bad as predicted.

Why? Scientists and public health experts cite a number of possible factors, including the continent’s youthful population and lessons learned from previous disease outbreaks. African governments also had precious time to prepare due to the relative isolation of many of their citizens from airports and other places where they could come into contact with global travellers.

Some scientists also are exploring the possibility that a tuberculosis vaccine routinely given to children in many African countries might be helping reduce deaths from COVID-19.

Another theory being considered is whether prior exposure to other coronaviruses including those that cause the common cold has provided a degree of resistance in some of the very communities once thought to be most vulnerable.

“There is a lot of circumstantial evidence,” Salim Abdool Karim, a South African infectious disease specialist who has advised the government on COVID-19, told Reuters, “but there is no smoking gun.”
LESSONS LEARNED

The virus hit Africa later than other continents, giving medical personnel time to set up field hospitals, source oxygen and ventilators, and learn from improvements in treatment elsewhere.

“We got the gift of time,” said Thumbi Mwangi, senior research fellow at the University of Nairobi’s Institute of Tropical and Infectious Diseases. “We had an amount of preparation that others did not.”

One reason could be that international travel is limited in many African countries, and travelling domestically can be more difficult than on other continents, Matshidiso Moeti, WHO regional director for Africa, told a news conference on Thursday.

The continent’s governments have also battled deadly infectious diseases such as Ebola, which killed more than 11,000 people in West Africa in 2013-16. So officials took notice when the new coronavirus started spreading around the globe rapidly early this year.

Many African countries were quick to introduce screening at airports, suspend flights from heavily affected nations and enforce social distancing measures and mask wearing.

Within a week of Kenya reporting its first case, schools were shut, incoming travellers had to undergo a mandatory quarantine and large gatherings were banned. Nigeria, Africa’s most populous nation, imposed a ban on interstate travel and a curfew. Many of its land borders had already been closed since August 2019 to cut down on smuggling, which helped fight the pandemic too.

South Africa introduced one of the world’s toughest lockdowns in late March, when the country had confirmed just 400 cases.

“Africa brought down the hammer earlier in terms of coronavirus lockdowns,” said Tim Bromfield, regional director for East and Southern Africa at the Tony Blair Institute for Global Change, a U.K.-based think tank.

Experts also point to the continent’s demographics.

Research has found that the risk of developing severe COVID-19 increases with age.

A 2019 United Nations report said 62% of sub-Saharan Africa’s population was under 25 and just 3% 65 or over. In the U.N.’s Europe and North America region, 28% were under 25 while 18% were age 65 and up.

Chikwe Ihekweazu, director general of the Nigeria Centre for Disease Control, attributed his country’s relatively low case mortality rate in part to the fact that the majority of patients were between the ages of 31 and 40.

CROSS-PROTECTION?

Scientists in several countries including South Africa are testing whether the century-old Bacille Calmette-Guérin (BCG) vaccine, widely used on the continent against tuberculosis, provides a degree of cross-protection.

BCG vaccines have been shown to protect against other viral respiratory illnesses, and a study published in the scientific journal Proceedings of the National Academy of Sciences in July found that countries with higher vaccination rates for tuberculosis had lower peak mortality rates from COVID-19.

Studies have also started in South Africa and Zimbabwe to assess the impact of past exposure to other coronaviruses.

More than half of Africa’s urban population is concentrated in slums, where access to water for hand washing is scarce, and physical distancing is near-impossible.

Diseases spread rapidly under such conditions, but some scientists wonder whether that may have been an unexpected boon in this case. There is some evidence that T cells developed by the body’s immune system after exposure to other common cold coronaviruses could help fight off COVID-19.

“I would say that is at least a plausible explanation as to why there are different levels of resistance to the virus in different populations,” said Thomas Scriba, an immunologist and deputy director of the South African Tuberculosis Vaccine Initiative.

Others are more sceptical.

“All other regions have been exposed to coronaviruses, have poor people and slums and have received BCG vaccination,” said Humphrey Karamagi, team leader for data and analytics at the WHO’s Africa office. “We are most probably looking at a mix of multiple factors working together - and not a single magic bullet.”

For Sam Agatre Okuonzi, from the Arua Regional Referral Hospital in Uganda, the doomsday predictions were informed by entrenched prejudices, including that the continent is prone to disease.

“COVID-19 has shattered a lot of biases about disease in general but also about Africa,” he told Thursday’s briefing. “The severity of the pandemic has not played out in line with the outrageous predictions.”

Additional reporting by Wendell Roelf in Cape Town and Tim Cocks in Johannesburg, MacDonald Dzirutwe in Harare, Ed McAllister in Dakar, Alexis Akwagyiram in Lagos, Katharine Houreld in Nairobi and Giulia Paravicini in Addis Ababa; Editing by Alexandra Zavis and David Gregorio

U.S. astronaut crew on SpaceX's Crew Dragon to cast ballots from space

WILL TRUMP ATTACK EMAIL VOTING?

WASHINGTON (Reuters) - Three NASA astronauts launching next month on SpaceX’s first operational Crew Dragon mission plan to vote in the upcoming presidential election from the International Space Station, the crew said Tuesday as they named the spacecraft “Resilience.”

SpaceX’s Crew Dragon Resilience capsule will carry NASA astronauts Michael Hopkins, Victor Glover, Shannon Walker and Japanese astronaut Soichi Noguchi to the space station Oct. 31 as the company’s first non-test mission after completing a successful two-man preliminary mission last summer.

“All of us are planning on voting from space,” Walker told a news conference, explaining that the three U.S. astronauts will fill out an electronic PDF file aboard the station some 250 miles above Earth and email it to elections officials.

The crew’s more than six month mission in space, enabled by SpaceX’s new gumdrop-shaped Crew Dragon space capsule, comes as NASA regains its capability of sending astronauts to space after nearly a decade-long dependence on Russia’s Soyuz vehicles.

Following tradition from SpaceX’s last crewed mission named “Endeavor,” which ended in August with a successful splashdown in the Gulf of Mexico, Hopkins said the crew chose the name “Resilience” as a tribute to a “challenging” 2020.

“I think all of us can agree that 2020 has certainly been a challenging year,” Hopkins said, adding that SpaceX and NASA have pressed on with launch plans despite a slew of events like the “global pandemic, economic hardships, civil unrest, isolation” that have punctuated this year.

SpaceX made a few tweaks to Crew Dragon’s heat shield and altitude sensors after analyzing data from the summer test flight carrying NASA astronauts Bob Behnken and Doug Hurley, the company’s Crew Dragon chief Benji Reed said during a separate press conference on Tuesday.

Reporting by Joey Roulette in Washington; Editing by Eric M. Johnson and David Gregorio

Ann Arbor, Michigan, Decriminalizes Magic Mushrooms, Psychedelic Plants
Authorities won’t investigate and arrest anyone for planting, cultivating, buying, transporting, distributing, engaging in practices with or possessing the plants.

ANN ARBOR, Mich. (AP) — The city of Ann Arbor has decriminalized psychedelic plants and fungi, including magic mushrooms, and police officers will no longer make them an enforcement focus.

City Council voted unanimously Sept. 21 in favor of a resolution declaring it the city’s lowest law enforcement priority, MLive.com reported. It means that authorities won’t investigate and arrest anyone for planting, cultivating, buying, transporting, distributing, engaging in practices with or possessing “entheogenic plants” or plant compounds.

The resolution defines entheogenic plants as plants and fungi that contain indole amines, tryptamines and phenethylamines “that can benefit psychological and physical wellness, support and enhance religious and spiritual practices, and can reestablish human’s inalienable and direct relationship to nature.”

The move applies to ayahuasca, ibogaine, mescaline, peyote, psilocybin mushrooms and other substances with hallucinogenic properties considered illegal under state and federal law.

 

Generating renewable hydrogen fuel from the sea

Researchers use membranes that remove salt from water to help 'split' sea water into fuel

PENN STATE

Research News

 

IMAGE: HERE IS A VISUAL REPRESENTATION OF HOW ION MOVEMENT IS AFFECTED BY A REVERSE OSMOSIS (RO) MEMBRANE VERSUS A CATION-EXCHANGE MEMBRANE. CHLORIDE IONS FROM THE SEAWATER ARE NOT ABLE TO... view more 

CREDIT: LOGAN RESEARCH GROUP

The power of the sun, wind and sea may soon combine to produce clean-burning hydrogen fuel, according to a team of Penn State researchers. The team integrated water purification technology into a new proof-of-concept design for a sea water electrolyzer, which uses an electric current to split apart the hydrogen and oxygen in water molecules.

This new method for "sea water splitting" could make it easier to turn wind and solar energy into a storable and portable fuel, according to Bruce Logan, Kappe Professor of Environmental Engineering and Evan Pugh University Professor.

"Hydrogen is a great fuel, but you have to make it," Logan said. "The only sustainable way to do that is to use renewable energy and produce it from water. You also need to use water that people do not want to use for other things, and that would be sea water. So, the holy grail of producing hydrogen would be to combine the sea water and the wind and solar energy found in coastal and offshore environments."

Despite the abundance of sea water, it is not commonly used for water splitting. Unless the water is desalinated prior to entering the electrolyzer -- an expensive extra step -- the chloride ions in sea water turn into toxic chlorine gas, which degrades the equipment and seeps into the environment.

To prevent this, the researchers inserted a thin, semipermeable membrane, originally developed for purifying water in the reverse osmosis (RO) treatment process. The RO membrane replaced the ion-exchange membrane commonly used in electrolyzers.

"The idea behind RO is that you put a really high pressure on the water and push it through the membrane and keep the chloride ions behind," Logan said.

In an electrolyzer, sea water would no longer be pushed through the RO membrane, but contained by it. A membrane is used to help separate the reactions that occur near two submerged electrodes -- a positively charged anode and a negatively charged cathode -- connected by an external power source. When the power is turned on, water molecules start splitting at the anode, releasing tiny hydrogen ions called protons and creating oxygen gas. The protons then pass through the membrane and combine with electrons at the cathode to form hydrogen gas.

With the RO membrane inserted, seawater is kept on the cathode side, and the chloride ions are too big to pass through the membrane and reach the anode, averting the production of chlorine gas.

But in water splitting, Logan noted, other salts are intentionally dissolved in the water to help made it conductive. The ion-exchange membrane, which filters ions by electrical charge, allows salt ions to pass through. The RO membrane does not.

"RO membranes inhibit salt motion, but the only way you generate current in a circuit is because charged ions in the water move between two electrodes," Logan said.

With the movement from the bigger ions restricted by the RO membrane, the researchers needed to see if there were enough tiny protons moving through the pores to keep a high electrical current.

"Basically, we had to show that what looked like a dirt road could be an interstate," Logan said. "We had to prove that we could get a high amount of current through two electrodes when there was a membrane between them that would not allow salt ions to move back and forth."

Through a series of experiments recently published in Energy & Environmental Science, the researchers tested two commercially available RO membranes and two cation-exchange membranes, a type of ion-exchange membrane that allows the movement of all positively charged ions in the system.

Each were tested for membrane resistance to ion movement, the amount of energy needed to complete reactions, hydrogen and oxygen gas production, interaction with chloride ions and membrane deterioration.

Logan explained that while one RO membrane turned out to be a "dirt road," the other performed well in comparison to the cation-exchange membranes. The researchers are still investigating why there was such a difference between the two RO membranes.

"The idea can work," he said. "We do not know exactly why these two membranes have been functioning so differently, but that is something we are going to figure out."

Recently, the researchers received a $300,000 grant from the National Science Foundation (NSF) to continue investigating sea water electrolysis. Logan hopes their research will play a critical role in reducing carbon dioxide emissions around the world.

"The world is looking for renewable hydrogen," he said. "For example, Saudi Arabia has planned to build a $5 billion hydrogen facility that is going to use sea water. Right now, they have to desalinate the water. Maybe they can use this method instead."

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Penn State researchers Le Shi, postdoctoral researcher in environmental engineering, Ruggero Rossi, postdoctoral researcher in environmental engineering, Derek Hall, assistant professor of energy engineering, Michael Hickner, professor of materials science and engineering and chemical engineering, and Christopher Gorski, associate professor of civil and environmental engineering, also contributed to the project.

The research was supported by the Stan and Flora Kappe Endowment in the Penn State Department of Civil and Environmental Engineering, the NSF, the United States Agency for International Development and the National Academy of Sciences, as well as additional funding from Penn State.

Guest Post: R0 and Herd Immunity

Beyond the Curve: Dr. Peter Lurie's COVID-19 Blog

September 12, 2020



This is a guest post by CSPI senior policy associate Ashley Hickson. See all Beyond the Curve posts.

A salutary benefit of the coronavirus pandemic is how it underscores that we’re all in this sticky predicament together. In order to “flatten the curve,” we all have to act in concert by wearing masks, washing hands, respecting social distancing recommendations, and generally minimizing contact with others. In epidemiology, this notion of interdependence is encapsulated in the concept of “herd immunity.” When most of a population is immune to an infectious disease, this provides indirect protection—or herd immunity—even to those who are not immune to the disease. In essence, once population immunity reaches a certain level, your chances of encountering someone who is infectious decline significantly. Depending on how infectious a disease is, usually 70% to 90% of a population needs to be immune for herd immunity to be established. But antibody levels, which measure prior exposure to the virus, are only around 25% in New York City, and considerably lower almost everywhere else. And this assumes that having antibodies assures immunity – something that has not yet been proved. Thus, the majority of the population remains susceptible to infection.

Given the high proportion of still-susceptible individuals, it’s unsurprising that COVID-19 outbreaks are persisting in cities such as Chicago, Houston, Los Angeles, Miami, and Phoenix. These dismal events paint a picture of an outbreak that is not contained and is still spreading rapidly.

How do epidemiologists portray the potential for spread of an infectious disease? Here, we turn to a technical term you may have heard about (and certainly will): the basic reproduction number, denoted as R0 (pronounced "R naught"). This measure describes the likely impact of a single infection—the number of people to whom an infected person will likely transmit the disease if no one is immune. It is one of the most fundamental metrics in the study of infectious disease outbreaks. So, if each person spreads the infection to two people and each cycle of infection takes a week, after about a month 16 people have been infected (of course, in that period, some of the 16 will have recovered).

To understand, from a theoretical standpoint, how R0 is calculated, consider a single infected person who contracts a disease at the beginning of an outbreak when no one is immune. To calculate how many people that person will infect, we must first figure out how long the person is infectious (2 to 14 days for COVID-19, according to the Centers for Disease Control and Prevention) and multiply that by the number of people they encounter per day. The number of contacts encountered can be calculated either at the individual- (via contact tracing) or population-level. Finally, we multiply that by the likelihood of infection for each encounter because, thankfully, the great majority of encounters do not lead to infection. That gives us the number of people who were infected by the first person. Presto! It’s R0 itself. (In practice, R0 is calculated using complex mathematical modeling with several additional inputs, but this illustrates the concepts behind the measure).

To help contextualize R0, the 1918 Spanish Influenza pandemic that killed 50 million people worldwide had an R0 that was estimated at between 1.4 and 2.8. The seasonal flu is estimated to have a R0 of approximately 1.3. Although estimates of R0 for COVID-19 vary, a range of 2 to 3 is often cited.

But, typically, shortly after an outbreak begins, some people become immune, so R can vary over time. This is where the effective reproductive number, or Rt, comes in (t stands for time). This number describes whether outbreaks are growing, remaining steady, or decreasing. An Rt value greater than 1 indicates that the epidemic is continuing to grow, an Rt value of 1 indicates that the outbreak is stable (with each case spreading the disease to one person), and an Rt less than 1 means the outbreak is on the wane and, all things being equal, will extinguish itself.

In addition to R0 and Rt, the dispersion factor, or “k” is also important in assessing an outbreak. K captures the idea that some people will spread the infection to many people, while others won’t spread it to anyone else, depending on social distancing and a host of other mitigating factors like mask wearing. For example, research is showing that people infected with COVID-19 are most infectious for a brief period of time; if an infected person enters a high-risk setting during this period, a super-spreading event could occur. Other interactions, even by the same individual, will confer lower risk. So k captures a level of complexity not contained in R0 or Rt: all exposures are not created equal. In general, the distribution of infectiousness depends upon the virus, characteristics of the potential spreader, and the circumstances in which infections are spread, including efforts to mitigate transmission.

We have examples of this domestically from outbreaks associated with small social events. These gatherings, such as bible study groups or birthday parties, are often more likely to take place indoors, creating an environment where the virus is able to spread easily from person to person. In Texas, a family hosted a birthday party for a total of 25 guests on May 30th. A single relative, unknowingly infected with the virus that causes COVID-19, spread the disease to seven family members (much greater than the typical value for R0); from this encounter, ten relatives who did not attend the party were infected. Across the nation, Greek fraternity and sorority houses, along with residence halls, have become the site of COVID-19 outbreaks at universities including Oklahoma State and the University of North Carolina at Chapel Hill. An outbreak at a sleep-away camp in Georgia last month resulted in 260 children and staffers contracting the virus less than a week after spending time together in close quarters. This example is the largest documented super-spreading event among children domestically, and gives pause for concern around the upcoming school year.

Unlike R0, the calculation for k is a bit too involved to discuss here. Suffice it to say, it captures the heterogeneity in likelihood of transmission in a given population. If a small number of individuals are responsible for a large number of transmissions, the value of k will be close to zero. As we continue to evaluate how this disease spreads, k will be a critical measure to consider when making decisions about reopening schools and businesses.

A research study modeling COVID-19 outbreaks across different countries discovered that k is around 0.1, implying that as few as 10% of infected individuals may be associated with 80% of transmissions. This provides a ray of hope: if we focus on potential super-spreading events like, ahem, indoor political rallies, we can have a disproportionate impact upon the course of the pandemic.



Ashley Hickson is a Senior Policy Associate focusing on healthy retail campaign initiatives. Prior to joining CSPI, she served as Director of Community Impact at the American Heart Association where she led her market’s food access strategies. Ashley is a Doctor of Public Health student at Johns Hopkins with a concentration in Health Equity and Social Justice. She has a passion for food justice and is a Bloomberg American Health Initiative Fellow in the obesity and food system focus area. She holds an MPH from the University of Texas Health Science Center