Study: Malicious bots are the primary pathogen of COVID-19 misinformation on social media

ELEVATED SCIENCE COMMUNICATIONS

Research News

 

La Jolla, Calif. (June 07, 2021) -- "The coronavirus pandemic has sparked what the World Health Organization has called an 'infodemic' of misinformation," said Dr. John W. Ayers, a scientist who specializes in public health surveillance. "But, bots --like those used by Russian agents during the 2016 American presidential election-- have been overlooked as a source of COVID-19 misinformation."

A new study published in JAMA Internal Medicine led by Dr. Ayers, Co-Founder of the Center for Data Driven Health and Vice Chief of Innovation within the Division of Infectious Diseases at the University of California San Diego in collaboration with the George Washington University and Johns Hopkins University suggests bots are the primary pathogen of COVID-19 misinformation on social media.

Identifying Bot Influence on Facebook Groups: A Case Study of Masks and COVID-19

The team identified public facebook groups that were heavily influenced by bots. The team measured how quickly the same URLs (or links) were shared in a sample of about 300,000 posts made to Facebook groups that shared 251,655 links.

When URLs are repeatedly shared by multiple accounts within seconds of one another, it indicates these are bot accounts controlled by automated software that coordinates their action. The team found that the Facebook groups most influenced by bots averaged 4.28 seconds between shares of identical links, compared to 4.35 hours for the Facebook groups least influenced by bots.

Among Facebook groups least or most influenced by bots, the team monitored posts that shared a link to the Danish Study to Assess Face Masks for the Protection Against COVID-19 Infection (DANMASK-19) randomized clinical trial published in the Annals of Internal Medicine. "We selected DANMASK-19 for our study because masks are an important public health measure to potentially control the pandemic and are a source of popular debate," said Dr. Davey Smith, study coauthor and Chief of Infectious Diseases at UC San Diego.

39 percent of all posts sharing the DANMASK-19 trial were made to Facebook groups that were the most influenced by bots. Whereas 9 percent of posts were made to Facebook groups the least influenced by bots.

20 percent of posts sharing the DANMASK-19 trial made to Facebook groups the most influenced by bots claimed masks harmed the wearer, contrary to scientific evidence. For example, one post read "Danish study proves...the harmfulness of wearing a mask." 50 percent of posts promoted conspiracies such as "corporate fact checkers are lying to you! All this to serve their Dystopian #Agenda2030 propaganda."

Posts sharing the DANMASK-19 trial made to Facebook groups the most influenced by bots were 2.3 times more likely to claim masks harm the wearer and 2.5 times more likely to make conspiratorial claims than posts made to Facebook groups made to Facebook groups the least influenced by bots.

The Threat of Automated Misinformation

"COVID-19 misinformation propaganda appears to be spreading faster than the virus itself," said Dr. Eric Leas, study coauthor and Assistant Professor at UC San Diego. "This is fueled by bots that can amplify misinformation at a rate far greater than ordinary users."

"Bots also appear to be undermining critical public health institutions. In our case study, bots mischaracterized a prominent publication from a prestigious medical journal to spread misinformation, said Brian Chu, study coauthor and medical student at UPenn. "This suggests that no content is safe from the dangers of weaponized misinformation."

"The amount of misinformation from bots we found suggests that bots' influence extends far beyond our case study," added Dr. Smith. "Could bots be fostering vaccine hesitancy or amplifying asian discrimination too?"

The team noted that the effect of automated misinformation is likely larger due to how it spills over into organic conversations on social media.

"Bots sharing misinformation could inspire ordinary people to propagate misinformed messages," said Zechariah Zhu, study coauthor and research associate with the Center for Data Drive Health at UC San Diego. "For example, bots may make platforms' algorithms think that automated content is more popular than it actually is, which can then lead to platforms actually prioritizing misinformation and disseminating it to an even larger audience," added Dr. David A. Broniatowski, Associate Director of the GW Institute for Data, Democracy, and Politics, and study coauthor.

A Call to Action to Address Automated Misinformation

"We must remember that unknown entities are working to deceive the public and promote misinformation. Their dangerous actions directly affect the public's health," said Dr. Mark Dredze, the John C. Malone Associate Professor of Computer Science at Johns Hopkins University and study coauthor.

Yet, solutions to eliminate bots and their misinformation campaigns are at hand the team notes.

"Our work shows that social media platforms have the ability to detect, and therefore remove, these coordinated bot campaigns," added Dr. Broniatowski. "Efforts to purge deceptive bots from social media platforms must become a priority among legislators, regulators, and social media companies who have instead been focused on targeting individual pieces of misinformation from ordinary users."

"If we want to correct the 'infodemic,' eliminating bots on social media is the necessary first step," concluded Dr. Ayers. "Unlike controversial strategies to censor actual people, silencing automated propaganda is something everyone can and should support."

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Spread of Misinformation About Face Masks and COVID-19 by Automated Software on Facebook

John W. Ayers, PhD, MA1; Brian Chu, BS2; Zechariah Zhu3; et alEric C. Leas, PhD, MPH4; Davey M. Smith, MD, MAS1; Mark Dredze, PhD5; David A. Broniatowski, PhD, SM6
Author Affiliations Article Information

JAMA Intern Med. Published online June 7, 2021. doi:10.1001/jamainternmed.2021.2498

The dangers of misinformation spreading on social media during the COVID-19 pandemic are known.1 However, software that allows individuals to generate automated content and share it via counterfeit accounts (or “bots”)2 to amplify misinformation has been overlooked, including how automated software can be used to disseminate original research while undermining scientific communication.

We analyzed conversations on public Facebook groups, a platform known to be susceptible to automated misinformation,3 concerning the publication of the Danish Study to Assess Face Masks for the Protection Against COVID-19 Infection (DANMASK-19) to explore automated misinformation.4 We selected DANMASK-19 because it was widely discussed (it was the fifth most shared research article of all time as of March 2021 according to Altmetric5) and demonstrated that masks are an important public health measure to control the pandemic.

Methods

Sample

We obtained the names of 563 Facebook groups in which a link to the publication of DANMASK-19 on the Annals of Internal Medicine website was posted and downloaded all available posts (N = 299 925) from these groups using CrowdTangle (crowdtangle.com). We limited our study period to the 5 days following the publication of DANMASK-19 (November 18, 2020, through November 22, 2020) because media interest is typically greatest initially. This study was exempted as not human participants research by the University of California, San Diego Human Research Protections Program. Additional details are provided in the eAppendix in the Supplement.

Measures

When identical links are posted in close succession, it suggests that automated software was used.2,3 We identified the subsets of Facebook groups that were the most or least likely to be affected by automation by calculating the frequency that identical links were posted to pairs of Facebook groups and the time that elapsed between these posts for all links (n = 251 656) shared during the study period. Adapting past operationalizations,3 a pair of Facebook groups that (1) hosted identical links 5 or more times and (2) at least half of these links being posted within less than 10 seconds would be considered the most affected by automation. Comparatively, Facebook groups in which the total time elapsed between identical links was in the top 90th percentage of time between postings were considered the least affected by automation. Facebook groups that were most affected by automation had a mean (SD) of 4.28 (3.02) seconds between shares of identical links compared with 4.35 (11.71) hours for those least affected by automation.

To quantify the extent to which Facebook groups were subject to misinformation, all posts that linked to DANMASK-19 in the groups most or least affected by automation were qualitatively coded by 2 authors (B.C. and Z.Z.) for 2 types of misinformation: (1) whether the primary conclusion of DANMASK-19 was misrepresented (eg, mask wearing harms the wearer) and (2) whether conspiratorial claims were made about DANMASK-19 (eg, claims of covert political/corporate control). A separate outcome for not including either form of misinformation was computed. Table 1 presents example posts. Coders disagreed on 3.9% of labels (Cohen κ = 0.76) and resolved disagreements unanimously with the first author (J.W.A.).
Analysis

The percentage of posts that linked to DANMASK-19 that included each type of misinformation or neither type was calculated separately for the sets of Facebook groups most and least affected by automation along with prevalence ratios comparing these percentages. Statistical significance was set to P < .05 and 95% confidence intervals were bootstrapped. Analyses were computed with R, version 3.6.1 (R Foundation).
Results

A total of 712 posts that provided direct links to DANMASK-19 were shared in 563 public Facebook groups. Of these, 279 posts (39%) that linked to DANMASK-19 were in Facebook groups most affected by automation, of which 17 were deleted and unavailable for further analysis. Sixty-two posts (9%) were made in Facebook groups that were least affected by automation, and 3 were deleted.

Among posts made to groups most affected by automation, 19.8% (95% CI,14.9%-24.5%) claimed masks harmed the wearer, 50.8% (95% CI, 44.6%-56.5%) made conspiratorial claims about the trial, and 43.9% (95% CI, 37.4%-49.6%) made neither claim (Table 2). In contrast, among posts made to groups least affected by automation, 8.5% (95% CI, 1.7%-15.2%) claimed masks harmed the wearer, 20.3% (95% CI, 10.2%-30.5%) made conspiratorial claims about the trial, and 72.9% (95% CI, 59.3%-81.4%) made neither claim.

The percentage of posts linking to DANMASK-19 that claimed that masks harmed the wearer was 2.3 (95% CI, 1.0-6.5) times higher in Facebook groups that were most affected by automation vs groups that were least affected by automation; conspiratorial claims (prevalence ratio, 2.5; 95% CI, 1.5-4.5) were also higher in Facebook groups that were most affected by automation. Making neither claim was more common in Facebook groups that were least affected by automation (prevalence ratio, 0.6; 95%CI, 0.5-0.7).
Discussion

A campaign that presumably used automated software6 promoted DANMASK-19 on Facebook groups to disseminate misinformation. The limitations of the study include that the entities responsible for organizing this automated campaign cannot be determined, only public Facebook groups were studied, and only a single high-profile study over a few days was evaluated.

Scientific journals are easy targets of automated software. Possible approaches to prevent misinformation due to dissemination of articles by automated software include legislation that penalizes those behind automation; greater enforcement of rules by social media companies to prohibit automation; and counter-campaigns by health experts.

Article Information

Accepted for Publication: April 15, 2021.

Published Online: June 7, 2021. doi:10.1001/jamainternmed.2021.2498

Corresponding Author: John W. Ayers, PhD MA; #333 CRSF 9500 Gilman Drive, La Jolla, CA 92093 (ayers.john.w@gmail.com).

Author Contributions: Drs Ayers and Broniatowski had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: All authors.

Acquisition, analysis, or interpretation of data: Ayers, Chu, Zhu, Leas, Smith, Broniatowski.

Drafting of the manuscript: Ayers, Chu, Zhu, Leas, Smith, Broniatowski.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Chu, Leas, Broniatowski.

Obtained funding: Smith.

Administrative, technical, or material support: Chu, Smith, Dredze, Broniatowski.

Supervision: Smith, Dredze, Broniatowski.

Conflict of Interest Disclosures: Dr Ayers reported owning equity in Directing Medicine, Health Watcher, and Good Analytics outside the submitted work. Dr Leas reported receiving consulting fees from Health Watcher and Good Analytics for similar work outside the context of these analyses. Dr Smith reported an endowment from the John and Mary Tu Foundation Endowment and grants from the National Institutes of Health during the conduct of the study and consulting fees from FluxErgy, Bayer, Arena Pharmaceuticals, and Linear Therapies outside the submitted work. Dr Dredze reported personal fees from Bloomberg LP and Good Analytics outside the submitted work. No other disclosures were reported.

Funding/Support: This work was supported by the Burroughs Wellcome Fund, National Institutes of Health grant AI036214, The John S. and James L. Knight Foundation to the George Washington University Institute for Data, Democracy, and Politics, and The John and Mary Tu Foundation.

Role of the Funder/Sponsor: The funding organizations had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Data Sharing Statement: The data used in the study are public in nature and are available from CrowdTangle. CrowdTangle prohibits providing raw data to anyone outside of a CrowdTangle user’s account. Anyone with a CrowdTangle account may access these corresponding data. Researchers may request CrowdTangle access at https://help.crowdtangle.com/en/articles/4302208-crowdtangle-for-academics-and-researchers.

Additional Contributions: We appreciate discussions and editing with Benjamin M. Althouse, PhD, ScM (Gates Foundation), Alicia Nobles, PhD (University of California, San Diego) and Christopher Longhurst MD (University of California San Diego). They were not compensated for their contributions.
References
1.
Saitz R, Schwitzer G. Communicating science in the time of a pandemic.  JAMA. 2020;324(5):443-444. doi:10.1001/jama.2020.12535
ArticlePubMedGoogle ScholarCrossref
2.
Broniatowski DA, Jamison AM, Qi S, et al. Weaponized health communication: Twitter bots and Russian trolls amplify the vaccine debate.  Am J Public Health. 2018;108(10):1378-1384. doi:10.2105/AJPH.2018.304567PubMedGoogle ScholarCrossref
3.
Giglietto F.,, Righetti N.,, Rossi L.,, & Marino G., It takes a village to manipulate the media: coordinated link sharing behavior during 2018 and 2019 Italian elections.  Information, Communication & Society. 2020;23(6):867-891. doi:10.1080/1369118X.2020.1739732Google ScholarCrossref
4.
Bundgaard H, Bundgaard JS, Raaschou-Pederson DET, et al. Effectiveness of adding a mask recommendation to other public health measures to prevent SARS-CoV-2 infection in Danish mask wearers: a randomized controlled trial.  Ann Intern Med. 2021;174(3):335-343. doi:10.7326/M20-6817PubMedGoogle ScholarCrossref
5.
Altmetric. Article detail page for effectiveness of adding a mask recommendation to other public health measures to prevent SARS-CoV-2 infection in Danish mask wearers. Accessed December 17, 2020. https://www.altmetric.com/details.php?domain=www.acpjournals.org&citation_id=94531651
6.
Allem JP, Ferrara E. Could social bots pose a threat to public health?  Am J Public Health. 2018;108(8):1005-1006. doi:10.2105/AJPH.2018.304512

Experiment evaluates the effect of human decisions on climate reconstructions

UNIVERSITY OF CAMBRIDGE

Research News

 

The first double-blind experiment analysing the role of human decision-making in climate reconstructions has found that it can lead to substantially different results.

The experiment, designed and run by researchers from the University of Cambridge, had multiple research groups from around the world use the same raw tree-ring data to reconstruct temperature changes over the past 2,000 years.

While each of the reconstructions clearly showed that recent warming due to anthropogenic climate change is unprecedented in the past two thousand years, there were notable differences in variance, amplitude and sensitivity, which can be attributed to decisions made by the researchers who built the individual reconstructions.

Professor Ulf Büntgen from the University of Cambridge, who led the research, said that the results are "important for transparency and truth - we believe in our data, and we're being open about the decisions that any climate scientist has to make when building a reconstruction or model."

To improve the reliability of climate reconstructions, the researchers suggest that teams make multiple reconstructions at once so that they can be seen as an ensemble. The results are reported in the journal Nature Communications.

Information from tree rings is the main way that researchers reconstruct past climate conditions at annual resolutions: as distinctive as a fingerprint, the rings formed in trees outside the tropics are annually precise growth layers. Each ring can tell us something about what conditions were like in a particular growing season, and by combining data from many trees of different ages, scientists are able to reconstruct past climate conditions going back hundreds and even thousands of years.

Reconstructions of past climate conditions are useful as they can place current climate conditions or future projections in the context of past natural variability. The challenge with a climate reconstruction is that - absent a time machine - there is no way to confirm it is correct.

"While the information contained in tree rings remains constant, humans are the variables: they may use different techniques or choose a different subset of data to build their reconstruction," said Büntgen, who is based at Cambridge's Department of Geography, and is also affiliated with the CzechGlobe Centre in Brno, Czech Republic. "With any reconstruction, there's a question of uncertainty ranges: how certain you are about a certain result. A lot of work has gone into trying to quantify uncertainties in a statistical way, but what hasn't been studied is the role of decision-making.

"It's not the case that there is one single truth - every decision we make is subjective to a greater or lesser extent. Scientists aren't robots, and we don't want them to be, but it's important to learn where the decisions are made and how they affect the outcome."

Büntgen and his colleagues devised an experiment to test how decision-making affects climate reconstructions. They sent raw tree ring data to 15 research groups around the world and asked them to use it to develop the best possible large-scale climate reconstruction for summer temperatures in the Northern hemisphere over past 2000 years.

"Everything else was up to them - it may sound trivial, but this sort of experiment had never been done before," said Büntgen.

Each of the groups came up with a different reconstruction, based on the decisions they made along the way: the data they chose or the techniques they used. For example, one group may have used instrumental target data from June, July and August, while another may have only used the mean of July and August only.

The main differences in the reconstructions were those of amplitude in the data: exactly how warm was the Medieval warming period, or how much cooler a particular summer was after a large volcanic eruption.

Büntgen stresses that each of the reconstructions showed the same overall trends: there were periods of warming in the 3rd century, as well as between the 10th and 12th century; they all showed abrupt summer cooling following clusters of large volcanic eruptions in the 6th, 15th and 19th century; and they all showed that the recent warming since the 20th and 21st century is unprecedented in the past 2000 years.

"You think if you have the start with the same data, you will end up with the same result, but climate reconstruction doesn't work like that," said Büntgen. "All the reconstructions point in the same direction, and none of the results oppose one another, but there are differences, which must be attributed to decision-making."

So, how will we know whether to trust a particular climate reconstruction in future? In a time where experts are routinely challenged, or dismissed entirely, how can we be sure of what is true? One answer may be to note each point where a decision is made, consider the various options, and produce multiple reconstructions. This would of course mean more work for climate scientists, but it could be a valuable check to acknowledge how decisions affect outcomes.

Another way to make climate reconstructions more robust is for groups to collaborate and view all their reconstructions together, as an ensemble. "In almost any scientific field, you can point to a single study or result that tells you what to hear," he said. "But when you look at the body of scientific evidence, with all its nuances and uncertainties, you get a clearer overall picture."

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A few common bacteria account for majority of carbon use in soil

NORTHERN ARIZONA UNIVERSITY

Research News

 

IMAGE: BACTERIAL "MINERS " SHOWN IN RELIEF WORKING TO PROCESS SOIL NUTRIENTS, SOME MORE EFFICIENTLY THAN OTHERS. BRADYRHIZOBIUM, ONE OF THE THREE TOP NUTRIENT PROCESSORS IDENTIFIED IN THE STUDY, IS SHOWN HERE... view more 

CREDIT: VICTOR O. LESHYK, CENTER FOR ECOSYSTEM SCIENCE AND SOCIETY, NORTHERN ARIZONA UNIVERSITY

Just a few bacterial taxa found in ecosystems across the planet are responsible for more than half of carbon cycling in soils. These new findings, made by researchers at Northern Arizona University and published in Nature Communications this week, suggest that despite the diversity of microbial taxa found in wild soils gathered from four different ecosystems, only three to six groups of bacteria common among these ecosystems were responsible for most of the carbon use that occurred.

Soil contains twice as much carbon as all vegetation on earth, and so predicting how carbon is stored in soil and released as CO2 is a critical calculation in understanding future climate dynamics. The research team, which included scientists from Pacific Northwest National Laboratory, Lawrence Livermore National Laboratory, University of Massachusetts-Amherst, and West Virginia University, is asking how such key bacterial processes should be accounted for in earth system and climate models.

"We found that carbon cycling is really controlled by a few groups of common bacteria," said Bram Stone, a postdoctoral researcher at the Center for Ecosystem Science and Society at Northern Arizona University who led the study. "The sequencing era has delivered incredible insight into how diverse the microbial world is," said Stone, who is now at Pacific Northwest National Laboratory. "But our data suggest that when it comes to important functions like soil respiration, there might be a lot of redundancy built into the soil community. It's a few common, abundant actors who are making the most difference."

Those bacteria--Bradyrhizobium, the Acidobacteria RB41, and Streptomyces--were better than their rarer counterparts at using both existing soil carbon and nutrients added to the soil. When carbon and nitrogen were added, these already dominant lineages of bacteria consolidated their control of nutrients, gobbling up more and growing faster relative to other taxa present. Though the researchers identified thousands of unique organisms, and hundreds of distinct genera, or collections of species (for example, the genus Canis includes wolves, coyotes, and dogs), only six were needed to account for more than 50 percent of carbon use, and only three were responsible for more than half the carbon use in the nutrient-boosted soil.

Using water labeled with special isotopes of oxygen, Stone and his team sequenced DNA found in soil samples, following the oxygen isotopes to see which taxa incorporated it into their DNA, a signal that indicates growth. This technique, called quantitative stable isotope probing (qSIP), allows scientists to track which bacteria are growing in wild soil at the level of individual taxa. Then the team accounted for the abundance of each taxon and modeled how efficiently bacteria consume soil carbon. The model that included taxonomic specificity, genome size, and growth predicted the measured CO2 release much more accurately than models that looked only at how abundant each bacterial group was. It also showed that just a few taxa produced most of the CO2 that the researchers observed.

"Better understanding how individual organisms contribute to carbon cycling has important implications for managing soil fertility and reducing uncertainty in climate change projections," said Kirsten Hofmockel, Microbiome Science Team Lead at Pacific Northwest National Laboratory and a co-author of the study. "This research teases apart taxonomic and functional diversity of soil microorganisms and asks us to consider biodiversity in a new way."

"The microbial demographic data that this technique reveals lets us ask more nuanced questions," said Stone. "Where we used to characterize a microbial community by its dominant function, the way a whole state is often reported to have voted 'for' or 'against' a ballot proposition, now, with qSIP, we can see who is driving that larger pattern--the 'election results,' if you will--at the level of individual microbial neighborhoods, city blocks.

"In this way, we can start to identify which soil organisms are performing important functions, like carbon sequestration, and study those more closely."

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This research was supported by grants from the Department of Energy's Biological Systems Science Division Program in Genomic Science (Nos. DE-SC0016207 and DE-SCSC0020172), and by the National Science Foundation (No. DEB-1645596). Research conducted at Lawrence Livermore National Laboratory was supported by the U.S. Department of Energy Office of Science, via awards SCW1679 and SCW1590, conducted under the auspices of DOE Contract DE-AC52- 07NA27344. Research conducted at Pacific Northwest National Laboratory was supported by the U.S. Department of Energy Office of Science, via awards FWP 68907 and FWP 74475, conducted under the auspices of DOE Contract DE-AC05-76RL01830.

 

How a Vietnamese raw pork snack could help us keep food fresh, naturally

Fermented meat snack is helping researchers develop a safe, all-natural food preservative

RMIT UNIVERSITY

Research News

 

IMAGE: VIETNAMESE FERMENTED PORK SNACK, NEM CHUA. view more 

CREDIT: RMIT UNIVERSITY

A traditional Vietnamese meat snack could hold the key to developing a safe and natural food preservative, addressing the twin global problems of food waste and food-borne illnesses.

Key Points

• Bacteria-killing compound discovered in Nem Chua, a fermented pork snack

• Toxic to bacteria but safe for humans, it's a natural alternative to artificial food preservatives

• New study reveals ideal growth conditions to potentially make the bacteria-killer at industrial scales

The fermented pork snack, Nem Chua, is eaten raw but does not cause food poisoning when prepared correctly.

This is because friendly bacteria that thrive in the fermented meat make a special compound that destroys more dangerous bacteria.

Now researchers at RMIT University in Melbourne, Australia, have shown how this natural bacteria-killing compound could be used to keep food fresh for longer.

Food waste is a global issue that costs around $US680 billion annually in industrialised countries, consumes nearly a quarter of the water used in agriculture and produces 8% of global greenhouse emissions.

Food-borne diseases like Listeria or Salmonella affect millions each year and can be life threatening for pregnant women, older people and those who are immunocompromised.

Co-lead researcher Professor Oliver Jones said changes in consumer habits have led to a greater demand for natural alternatives to artificial food preservatives.

"Scientists have known about these bacteria-killing compounds for many years but the challenge is to produce them in large enough quantities to be used by the food industry," said Jones, Associate Dean of Biosciences and Food Technology at RMIT.

"The Nem Chua compound is colourless, odourless, tasteless and very resilient.

"Through this new research, we've identified the right growth conditions that would enable us to make it in large amounts, potentially at industrial scales.

"With further development, we hope this could be an effective, safe and all-natural solution for both food waste and food-borne disease."

Bacteria-killing weapon

A team of RMIT researchers was inspired to investigate Nem Chua for its potential antibacterial properties after travelling to Vietnam and observing people eating the raw meat snack without getting sick, despite the hot and humid climate.

The team, led by Professor Andrew Smith (now at Griffith University) and Dr Bee May, discovered a new type of bacteria-killing compound in Nem Chua.

Plantacyclin B21AG is one of a group of compounds known as bacteriocins, which are produced by bacteria to destroy rival bacterial strains.

Bacteriocins form holes in the membranes of target bacteria. This causes the contents of the cell to leak out - effectively killing the bacteria.

The problem is most bacteriocins only work against one or two types of bacteria and they are not very stable in different environmental conditions.

Only one - Nisin, which came to market in the 1960s - is currently licensed for use as a food preservative, in a market estimated to be worth more than $US513 million in 2020, but this compound is temperature and pH sensitive limiting its use.

Tough and effective

The Nem Chua-derived compound is more robust than Nisin and is effective against a wide range of bacteria even after exposure to a range of environments typical in food processing.

It can survive being heated to 90C for 20 minutes and remains stable across high and low pH levels.

The compound can also destroy a range of disease-causing organisms commonly found in food including potentially life-threating Listeria, which can survive refrigeration and even freezing.

Co-lead researcher Dr Elvina Parlindungan, who completed the new study as part of her PhD research at RMIT, is now a postdoctoral fellow at APC Microbiome, part of University College Cork in Ireland.

"Using bacteriocins as food preservatives effectively means we are turning bacteria's own toxic weapons against them - harnessing nature's smart solutions to tackle our big challenges," Parlindungan said.

"In the future, these compounds might also be useful as an antibiotic in human medicine."

Researchers at RMIT's School of Science have begun experimenting with methods to further purify the compound and are planning to incorporate it into test food products.

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The team is keen to collaborate with potential industry partners to further develop the technology.

This work was supported by a PhD scholarship from the Indonesian Endowment Fund for Education (LPDP), part of the Ministry of Finance of the Republic of Indonesia, awarded to Parlindungan.

'Factors that influence growth and bacteriocin production in Lactiplantibacillus plantarum B21,' with co-author Dr Chaitali Dekiwadia (RMIT Microscopy and Microanalysis Facility), is published in Process Biochemistry (DOI:?10.1016/j.procbio.2021.05.009).

CAPTION

Listeria bacteria (green) dying after exposure to Plantacyclin B21AG. The bumps visible on many of the cells are the cell contents beginning to leak out.

CREDIT

Dr Elvina Parlindungan

CAPTION

Left: Listeria bacteria, alive and with intact cell membranes. Right: The same bacteria after exposure to Plantacyclin B21AG, dead and with the cell membranes destroyed.

CREDIT

Dr Elvina Parlindungan

 

'Asian American': A rallying cry that united Asians in the 1960s but is it still relevant?

How Asian Americans' public policy opinions are divided by generation and national origin, especially on immigration

DARTMOUTH COLLEGE

Research News

IMAGE: SIMPLIFIED PROFILES OF CLASSES COMPILED BY SUNMIN KIM BASED ON DATA FROM THE NATIONAL ASIAN AMERICAN SURVEY. view more 

CREDIT: TABLE PROVIDED BY SUNMIN KIM.

The recent attacks against Asian Americans have put Asians in the U.S. in the spotlight. Many of the victims are first-generation immigrants in ethnic communities, while those rallying for the victims are second-generation Asian Americans. A new Dartmouth study explores who Asian Americans are today and the range of identities this category encompasses.

The study, by Sunmin Kim, an assistant professor of sociology at Dartmouth, is based on 2016 pre-election survey data and found that Asian Americans tend to have progressive opinions about public policy, including on healthcare, education, climate change, and racial justice, but diverge on views toward Muslim immigration.

As previous research has reported, in 1968, the pan-ethnic category, "Asian American" was born, as Chinese students and Japanese students at University of California, Berkeley, wanted a collective term to refer to both their student associations that could be used to help mobilize their political action. As a result, they established the Asian American Political Alliance, for which a chapter was also created at San Francisco State College.

"With the rise of radical social movements in the 1960s, the term 'Asian Americans' gained further traction as Asians protested domestic racism and the Vietnam War, often viewing both racism and U.S. intervention in Vietnam as originating from imperialism," says Kim. "If the category Asian American can be created, then a logical extension of that argument is that it can also be broken down, reversed or remade in a different context."

To determine whether Asian Americans still rally behind a common cause, the study drew on data from the 2016 pre-election National Asian American Survey (NAAS). With over 3,100 respondents representing nine national origin and ethnic groups in the U.S. (Chinese, Filipino, Indian, Vietnamese, Korean, Japanese, Hmong, Cambodian, and Native Hawaiian-Pacific Islander), and interviews conducted in English and 10 other languages, as well as comparison data on whites, Blacks, and Latinos, the survey is one of the most comprehensive of its kind. Kim's research focused on the data from the nine Asian groups.

Participants in the NAAS survey were asked seven questions on public policy. Did they support or oppose: the healthcare law passed by Barack Obama and Congress in 2010; federal government spending to make public colleges tuition-free; accepting Syrian refugees into the U.S.; legal possession of small amounts of marijuana; banning Muslim immigrants from entering the U.S.; establishing stricter emissions limits for power plants; and government initiatives to give Blacks equal rights with whites?

The study's findings are published in RSF: The Russell Sage Foundation Journal of the Social Sciences in the issue "Asian Americans and the Immigrant Integration Agenda."

The results showed that Asian Americans support the Affordable Care Act, free college tuition, emissions limits for power plants, and racial equality initiatives for Blacks. However, 18% supported the Muslim travel ban, 31% opposed accepting Syrian refugees into the U.S. and 49% opposed the legalization of marijuana.

"Although Asian Americans are often Democrat-leaning, their liberal views are somewhat dampened when it comes to questions on Muslim immigration and Syrian refugees as compared to their opinions on other liberal public policies," says Kim.

The results indicated that Asian Americans with reservations about immigration are more likely to be foreign born than native born and less educated, as opposed to progressives, who are more likely to be born in the U.S.

"There's a considerable number of Asian Americans who are leaning towards these ideas of anti-immigrant sentiment even though they are immigrants themselves," says Kim. "This divergence is one that political candidates may be inclined to tap into in the future, as they work to build a larger coalition. This was the case with Sery Kim, a Korean-American Republican, who delivered anti-Chinese remarks in March during her campaign for Texas' 6th Congressional District."

The research by Sunmin Kim also found that Asian Americans were more liberal than native whites, just as liberal as Latinos, and less liberal than Blacks.

As part of the analysis, the study applied a statistical technique designed to develop a typology, which is similar to the way that we perceive different types of people in various contexts. The analysis revealed two distinct subgroups of Asian Americans:

• There are the second- or third-generation Asian Americans who are young, liberal, college educated, middle class, and racially conscious. These individuals may be of East Asian and Indian descent. Kim speculates that this group includes professionals such as lawyers and doctors, who live in the big cities such San Francisco or New York City and are integrated physically into white residential areas and working spaces.

• There is also an older, first-generation of Asian American immigrants who were born outside the U.S. and are relatively more conservative. They are more likely to be men than women and are of Southeast Asian heritage, such as Cambodian or Vietnamese. Kim speculates that members of this group may not be proficient in English.

"While many second-generation immigrants today may identify with the Asian American label, if you ask a first- generation immigrant what they think of the term, they probably will be more inclined to identify with their national origin, rather than being associated with such a commonality," says Kim.

"There's a generational divide among Asian Americans, which is ironically present in the recent attacks on Asian Americans: the older, more conservative first-generation immigrants have often been the victims of these attacks rather than the younger, more liberal and highly educated second-generation," adds Kim.

The study reports that, according to The Making of Asian America by Erika Lee at the University of Minnesota, the Asian American category comprises 24 ethnic groups, each with a distinct culture. As Kim explains in the conclusion of his paper, understanding division within Asian Americans is essential to sustaining the politics of this category and to addressing differences and inequality among Asian Americans today.

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Plant-based and/or fish diets may help lessen severity of COVID-19 infection

Associated with 73% and 59% lower odds, respectively, of moderate to severe disease

BMJ

Research News

 

Plant-based and/or fish (pescatarian) diets may help lower the odds of developing moderate to severe COVID-19 infection, suggest the findings of a six-country study, published in the online journal BMJ Nutrition Prevention & Health.

They were associated with 73% and 59% lower odds, respectively, of severe disease, the findings indicate.

Several studies have suggested that diet might have an important role in symptom severity and illness duration of COVID-19 infection. But, as yet, there's little evidence to confirm or refute this theory.

To explore this further, the researchers drew on the survey responses of 2884 frontline doctors and nurses with extensive exposure to SARS-CO-v2, the virus responsible for COVID-19 infection, working in France, Germany, Italy, Spain, the UK and the US.

The participants were all part of a global network of healthcare professionals registered with the Survey Healthcare Globus network for healthcare market research. The researchers used this network to identify clinicians at high risk of COVID-19 infection as a result of their jobs.

The online survey, which ran between July and September 2020, was designed to elicit detailed information about respondents' dietary patterns, based on a 47-item food frequency questionnaire, over the previous year, and the severity of any COVID-19 infections they had had, using objective criteria.

The survey also gathered information on personal background, medical history, medication use, and lifestyle.

The various diets were combined into plant-based (higher in vegetables, legumes, and nuts, and lower in poultry and red and processed meats); pescatarian/plant-based (as above, but with added fish/seafood); and low carb-high protein diets.

Some 568 respondents (cases) said they had had symptoms consistent with COVID-19 infection or no symptoms but a positive swab test for the infection; 2316 said they hadn't had any symptoms/tested positive (comparison group).

Among the 568 cases, 138 clinicians said they had had moderate to severe COVID-19 infection; the remaining 430 said they had had very mild to mild COVID-19 infection.

After factoring in several potentially influential variables, including age, ethnicity, medical specialty, and lifestyle (smoking, physical activity), respondents who said they ate plant-based diets' or plant-based/pescatarian diets had, respectively, 73% and 59% lower odds of moderate to severe COVID-19 infection, compared with those who didn't have these dietary patterns.

And compared with those who said they ate a plant-based diet, those who said they ate a low carb-high protein diet had nearly 4 times the odds of moderate to severe COVID-19 infection.

These associations held true when weight (BMI) and co-existing medical conditions were also factored in.

But no association was observed between any type of diet and the risk of contracting COVID-19 infection or length of the subsequent illness.

This is an observational study, and so can't establish cause, only correlation. It also relied on individual recall rather than on objective assessments, and the definition of certain dietary patterns may vary by country, point out the researchers.

Men outnumbered women in the study, so the findings may not be applicable to women, they add.

But plant-based diets are rich in nutrients, especially phytochemicals (polyphenols, carotenoids), vitamins and minerals, all of which are important for a healthy immune system, say the researchers.

And fish is an important source of vitamin D and omega-3 fatty acids, both of which have anti-inflammatory properties, they add.

"Our results suggest that a healthy diet rich in nutrient dense foods may be considered for protection against severe COVID-19," they conclude.

"The trends in this study are limited by study size (small numbers with a confirmed positive test) and design (self-reporting on diet and symptoms) so caution is needed in the interpretation of the findings," comments Deputy Chair of the NNEdPro Nutrition and COVID-19 Taskforce, Shane McAuliffe.

"However, a high quality diet is important for mounting an adequate immune response, which in turn can influence susceptibility to infection and its severity."

He adds:"This study highlights the need for better designed prospective studies on the association between diet, nutritional status and COVID-19 outcomes."

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Externally peer reviewed? Yes
Evidence type: Observational; survey data
Subjects: People

 

E-scooter injuries most likely at weekends and after alcohol-fueled risk-taking

Much stricter regulation and technical modifications to design required to lessen injury risk

BMJ

Research News

 

E-scooter injuries are most likely to occur at the weekend and after alcohol-fuelled risk taking, such as kerb jumping, reveals an analysis of the pattern and timing of these injuries in one European city, and published online in Emergency Medicine Journal.

Much stricter regulations on the use of e-scooters, plus technical modifications to their design, are required to lessen the risk of injury, say the researchers.

E-scooters have become popular in major European cities since their initial licensing in June 2019, prompted by their ready availability and environmental concerns.

With 3.8 million residents and almost 14 million tourists every year, Berlin was chosen by e-scooter manufacturers as a test site for short-distance journeys ('micromobility'). And in September 2019, more than 11,000 e-scooters entered circulation in the city.

Few studies have looked at the patterns of injury associated with e-scooter use in European cities. To plug this knowledge gap, the researchers looked at e-scooter injuries treated at four emergency departments in central Berlin for the six months between June and December 2019.

At two of the emergency departments, injured patients were asked to fill in questionnaires on the likely cause of the incident, previous experience with e-scooters, possession of a driving licence, whether they had been drinking before the incident, and whether they had worn a helmet.

During the 6-month study period, 248 patients were treated at the four emergency departments after sustaining an e-scooter injury.

The riders' average age was 29, but ranged from 5 to 81, with the bulk of injuries occurring in those aged between 26 and 40. Just over half the patients were male (52%). Nearly six out of 10 (58%) were resident Berliners; 41% were tourists.

Most incidents (75%) occurred between July and September, peaking between noon and 18:00 hours (40%) and between 18:00 hours and midnight (29%).

E-scooter injuries were also higher at the weekend (58%) than on weekdays. In 20 patients (8%), the incidents happened on the way to or from work.

The primary cause of the injury was falling off the scooter because of loss of control, due to not paying attention, single handed driving, kerb jumping, inexperience, or going too fast.

Injuries were also caused by contact with the sharp edges or protruding screws of the e-scooter during acceleration or when pushing off from the ground or while trying to brake.

Pedestrians were injured in 12 cases (5%), either by getting hit by an e-scooter (9) or by tripping over a parked vehicle (3).

Leg and arm injuries were recorded in 178 patients and made up most of the injuries (72%). Thirteen of the 17 patients with a leg fracture required surgery; but most leg injuries were soft tissue injuries.

Arms were more likely to be fractured than legs (17% vs 6%); 21 of these patients (8%) required surgery. Four people dislocated a shoulder.

Head injuries (135) were sustained by 101 patients: soft tissue injuries (27%); fractures (19%); and tooth damage (17%). One patient had a brain bleed. Thirty two (13%) also had a traumatic brain injury of mild severity, 22 of whom were admitted to hospital.

In total, 1 in 4 patients (61;25%) was admitted to hospital: 57 of them (23%) required surgery, with the average stay lasting 3 days, but ranging from 1-12 days.

Of the 120 patients who filled in the questionnaire, two thirds (82; 68%) had a driving licence and around half (58; 48%) had driven an e-scooter before.

One in five patients (49; 20%) tested positive on the alcohol breath test; 15 of them had sustained traumatic brain injury (31%).

A positive breath test was associated with a fivefold increase in the odds of traumatic brain injury and a doubling in the odds of hospital admission, even if the drivers were experienced in handling e-scooters.

Previous experience with e-scooters was associated with a threefold increase in the odds of traumatic brain injury. Only 1% of riders wore a helmet.

The researchers acknowledge that their study was confined to four central emergency departments in one city and that patients at only two of the emergency departments filled in the questionnaire.

Nevertheless, the study reports on the largest cohort of patients involved in e-scooter incidents in Europe, they point out.

Their findings prompt the researchers to call for much tighter regulations for e-scooter users. "These should include the wearing of helmets, an age limit of 18 years, a ban on alcohol and a strict adherence to traffic regulations, such as avoiding driving on pavements," they write.

"By performing technical modifications to the e-scooter platforms, providers can help to eliminate an additional source of injury," they add.

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Externally peer reviewed? Yes
Evidence type: Observational
Subjects: People