Genetic analysis indicates that oysters appear to be the reservoir — for most instances of humanly acquired norovirus illnesses — Sewage laced seawater may be the mechanism that keeps the infection cycle going

© 2015 Peter Free

Citation — to study

Yongxin Yu, Hui Cai, Linghao Hu, Rongwei Lei, Yingjie Pan, Shuling Yan, and Yongjie Wang, Molecular epidemiology of oyster-related human noroviruses: Global genetic diversity and temporal-geographical distribution from 1983 to 2014, Applied and Environmental Microbiology, DOI: 10.1128/AEM.01729-15 (Accepted manuscript posted online, 28 August 2015)

Citation — to press release

American Society for Microbiology, Oysters Harbor, Transmit Human Norovirus: Avoid Raw Ones, ASM.org (28 August 2015)

The public health problem

From the press release:

Norovirus causes stomach pain, diarrhea, nausea, and vomiting.

It is extremely contagious, and infects more than 6 percent of the US population, annually, resulting in around 20 million cases, including 56,000-71,000 hospitalizations and 570-800 deaths, according to the Centers for Disease Control and Prevention.

Even touching a contaminated surface can result in infection.

© 2015 American Society for Microbiology, Oysters Harbor, Transmit Human Norovirus: Avoid Raw Ones, ASM.org (28 August 2015) (paragraph split)

If you think nauseous diarrhea boosts your virility . . .

From the abstract:

Noroviruses (NoVs) are a leading cause of epidemic and sporadic cases of acute gastroenteritis worldwide.

Oysters are well recognized as the main vectors of environmentally transmitted NoVs, and disease outbreaks linked to oyster consumption have been commonly observed.

Here, to quantify the genetic diversity, temporal distribution and circulation of oyster-related NoVs on a global scale, 1,077 oyster-related NoV sequences were downloaded from both NCBI GenBank and Noronet outbreak database during 1983–2014, then screened for sequence quality control.

665 sequences with reliable information were obtained and subsequently subjected to genotyping and phylogenetic analyses.

The results indicated that the majority of oyster-related NoV sequences were obtained from coastal countries and regions, and the number of sequences in these regions was unevenly distributed.

Moreover, more than 80% human NoV genotypes were detected in oyster samples or oyster-related outbreaks.

[A]related convergence of the circulation trend was found between oyster-related NoV sequences and human pandemic outbreaks.

This suggests that oysters act not only as a vector of NoV by way of environmental transmission, but that they also serve as an important viral reservoir of human NoVs.

© 2015 Yongxin Yu, Hui Cai, Linghao Hu, Rongwei Lei, Yingjie Pan, Shuling Yan, and Yongjie Wang, Molecular epidemiology of oyster-related human noroviruses: Global genetic diversity and temporal-geographical distribution from 1983 to 2014, Applied and Environmental Microbiology, DOI: 10.1128/AEM.01729-15 (Accepted manuscript posted online, 28 August 2015) (at Abstract) (paragraph split)

The moral? — Don’t eat raw oysters

Common sense:

[Yongjie] Wang advised that people who eat oysters and other shellfish should eat them fully cooked, and never raw. He also urged development of a reliable method for detecting noroviruses in oysters, and a worldwide oyster-related norovirus outbreak surveillance network.

© 2015 American Society for Microbiology, Oysters Harbor, Transmit Human Norovirus: Avoid Raw Ones, ASM.org (28 August 2015)

An attempt to reproduce the original findings of 100 psychology experiments — managed to do so in approximately only 36 to 47 percent — depending upon which standard of reproducibility was used

© 2015 Peter Free

Citation — to study

Open Science Collaboration, Estimating the reproducibility of psychological science, Science 349(6251): 943- [not paginated], DOI: 10.1126/science.aac4716 (28 August 2015) (Collaboration’s participants are listed at the end of this posting)

Citation — to press release

University of Virginia, Massive study reports challenges in reproducing published psychology findings, ScienceDaily (27 August 2015)

The field of psychological research has arguably had problems with scientific rigor

And newly published findings from the Open Science Collaboration are mildly concerning:

We conducted replications of 100 experimental and correlational studies published in three psychology journals using high-powered designs and original materials when available.

There is no single standard for evaluating replication success. Here, we evaluated reproducibility using significance and P values, effect sizes, subjective assessments of replication teams, and meta-analysis of effect sizes.

Replication effects were half the magnitude of original effects, representing a substantial decline. Ninety-seven percent of original studies had statistically significant results.

Thirty-six percent of replications had statistically significant results;

47% of original effect sizes were in the 95% confidence interval of the replication effect size;

39% of effects were subjectively rated to have replicated the original result;

and

if no bias in original results is assumed, combining original and replication results left 68% with statistically significant effects.

Correlational tests suggest that replication success was better predicted by the strength of original evidence than by characteristics of the original and replication teams.

© 2015 Open Science Collaboration, Estimating the reproducibility of psychological science, Science 349(6251): 943- [not paginated], DOI: 10.1126/science.aac4716 (28 August 2015) (at Abstract and Structured Abstract) (extracts)

This was a major effort

Methodologically:

Starting in November 2011, we constructed a protocol for selecting and conducting high-quality replications. Collaborators joined the project, selected a study for replication from the available studies in the sampling frame, and were guided through the replication protocol.

The replication protocol articulated the process of selecting the study and key effect from the available articles, contacting the original authors for study materials, preparing a study protocol and analysis plan, obtaining review of the protocol by the original authors and other members within the present project, registering the protocol publicly, conducting the replication, writing the final report, and auditing the process and analysis for quality control.

Project coordinators facilitated each step of the process and maintained the protocol and project resources.

Replication materials and data were required to be archived publicly in order to maximize transparency, accountability, and reproducibility of the project (https://osf.io/ezcuj).

In total, 100 replications were completed by 270 contributing authors.

There were many different research designs and analysis strategies in the original research. Through consultation with original authors, obtaining original materials, and internal review, replications maintained high fidelity to the original designs.

Analyses converted results to a common effect size metric [correlation coefficient (r)] with confidence intervals (CIs).

The units of analysis for inferences about reproducibility were the original and replication study effect sizes. The resulting open data set provides an initial estimate of the reproducibility of psychology and correlational data to support development of hypotheses about the causes of reproducibility.

© 2015 Open Science Collaboration, Estimating the reproducibility of psychological science, Science 349(6251): 943- [not paginated], DOI: 10.1126/science.aac4716 (28 August 2015) (at Methods) (paragraph split)

The team concluded that

In the paper’s structured abstract:

No single indicator sufficiently describes replication success, and the five indicators examined here are not the only ways to evaluate reproducibility. Nonetheless, collectively these results offer a clear conclusion:

A large portion of replications produced weaker evidence for the original findings despite using materials provided by the original authors, review in advance for methodological fidelity, and high statistical power to detect the original effect sizes.

© 2015 Open Science Collaboration, Estimating the reproducibility of psychological science, Science 349(6251): 943- [not paginated], DOI: 10.1126/science.aac4716 (28 August 2015) (at Structured Abstract: Conclusion) (paragraph split)

Perhaps too much waffling?

Consider these statements — my underlines added:

After this intensive effort to reproduce a sample of published psychological findings, how many of the effects have we established are true? Zero.

And how many of the effects have we established are false? Zero.

Is this a limitation of the project design? No. It is the reality of doing science, even if it is not appreciated in daily practice.

Humans desire certainty, and science infrequently provides it. As much as we might wish it to be otherwise, a single study almost never provides definitive resolution for or against an effect and its explanation.

The original studies examined here offered tentative evidence; the replications we conducted offered additional, confirmatory evidence.

In some cases, the replications increase confidence in the reliability of the original results; in other cases, the replications suggest that more investigation is needed to establish the validity of the original findings.

Scientific progress is a cumulative process of uncertainty reduction that can only succeed if science itself remains the greatest skeptic of its explanatory claims.

The present results suggest that there is room to improve reproducibility in psychology.

Any temptation to interpret these results as a defeat for psychology, or science more generally, must contend with the fact that this project demonstrates science behaving as it should.

Hypotheses abound that the present culture in science may be negatively affecting the reproducibility of findings.

An ideological response would discount the arguments, discredit the sources, and proceed merrily along. The scientific process is not ideological.

Science does not always provide comfort for what we wish to be; it confronts us with what is.

Moreover, as illustrated by the Transparency and Openness Promotion (TOP) Guidelines (http://cos.io/top) (37), the research community is taking action already to improve the quality and credibility of the scientific literature.

© 2015 Open Science Collaboration, Estimating the reproducibility of psychological science, Science 349(6251): 943- [not paginated], DOI: 10.1126/science.aac4716 (28 August 2015) (at paper’s Conclusion) (paragraph split)

The team’s mushy conclusion is typical of the Establishment’s behind-protecting nature

I am pretty sure a handful of politically adept folks slaved over how to make the study’s results seem less distressing than they (maybe) are.

First — just because science is skeptical, and this particular attempt to reproduce previous results exemplifies that worthy skepticism — the uncovered state of affairs emphatically does not mean that unreplicated previous results were necessarily attained with laudable scientific rigor.

In other words, decent science performed on the heels of lousy science does not an overall “sloppiness cure” make. The team admits as much with its statement that:

The present results suggest that there is room to improve reproducibility in psychology.

It is difficult to pretend that everything in the field is marching swimmingly along, when one simultaneously admits that something is awry enough to require improvement.

Second — the drift of the statement that — “The scientific process is not ideological” — defies human nature. And no one is arguing that we should “discount the arguments, discredit the sources, and proceed merrily along.”

We are instead asserting that psychology (and science and medicine generally) have too many unreplicable findings. And we want to know why this is so. Consequently, the thrust of the team’s observation that:

Hypotheses abound that the present culture in science may be negatively affecting the reproducibility of findings —

is on the money, but its semantically dismissive tone is not.

Profit and prestige motives in science and medical research today generally smell, and we need to root out their excessive influences, so as to preserve the scientific profession’s intellectual integrity. Alternatively, it may that commonly used statistical techniques and/or (for example) reviews of potentially confounding variables are ineffective.

The moral? — Significant amounts of psychological research are evidently off methodological and statistical track and need to be corrected

Let’s not make excuses that sound statistically reasonable, but fly in the face of “our” own accumulated evidence.

For example, if p-values — or other measure(s) of reliability — are in the 95 percent (non-randomly caused) range, it defies common sense credulity that more than half of them would subsequently be found to be noticeably less convincing — if our techniques are as useful as we seem to think they are. Which, I assume, is the ultimate source of the paper’s conclusion that the methods or analyses underlying psychological research need improvement.

The Open Science Collaboration

The Collaboration’s contributors deserve recognition:

Alexander A. Aarts, Joanna E. Anderson, Christopher J. Anderson, Peter R. Attridge, Angela Attwood, Jordan Axt, Molly Babel, Štěpán Bahník, Erica Baranski, Michael Barnett-Cowan, Elizabeth Bartmess, Jennifer Beer, Raoul Bell, Heather Bentley, Leah Beyan, Grace Binion, Denny Borsboom, Annick Bosch, Frank A. Bosco, Sara D. Bowman, Mark J. Brandt, Erin Braswell, Hilmar Brohmer, Benjamin T. Brown, Kristina Brown, Jovita Brüning, Ann Calhoun-Sauls, Shannon P. Callahan, Elizabeth Chagnon, Jesse Chandler, Christopher R. Chartier, Felix Cheung, Cody D. Christopherson, Linda Cillessen, Russ Clay, Hayley Cleary, Mark D. Cloud, Michael Cohn, Johanna Cohoon, Simon Columbus, Andreas Cordes, Giulio Costantini, Leslie D. Cramblet Alvarez, Ed Cremata, Jan Crusius, Jamie DeCoster, Michelle A. DeGaetano, Nicolás Della Penna, Bobby den Bezemer, Marie K. Deserno, Olivia Devitt, Laura Dewitte, David G. Dobolyi, Geneva T. Dodson, M. Brent Donnellan, Ryan Donohue, Rebecca A. Dore, Angela Dorrough, Anna Dreber, Michelle Dugas, Elizabeth W. Dunn, Kayleigh Easey, Sylvia Eboigbe, Casey Eggleston, Jo Embley, Sacha Epskamp, Timothy M. Errington, Vivien Estel, Frank J. Farach, Jenelle Feather, Anna Fedor, Belén Fernández-Castilla, Susann Fiedler, James G. Field, Stanka A. Fitneva, Taru Flagan, Amanda L. Forest, Eskil Forsell, Joshua D. Foster, Michael C. Frank, Rebecca S. Frazier, Heather Fuchs, Philip Gable, Jeff Galak, Elisa Maria Galliani, Anup Gampa, Sara Garcia, Douglas Gazarian, Elizabeth Gilbert, Roger Giner-Sorolla, Andreas Glöckner, Lars Goellner, Jin X. Goh, Rebecca Goldberg, Patrick T. Goodbourn, Shauna Gordon-McKeon, Bryan Gorges, Jessie Gorges, Justin Goss, Jesse Graham, James A. Grange, Jeremy Gray, Chris Hartgerink, Joshua Hartshorne, Fred Hasselman, Timothy Hayes, Emma Heikensten, Felix Henninger, John Hodsoll, Taylor Holubar, Gea Hoogendoorn, Denise J. Humphries, Cathy O.-Y. Hung, Nathali Immelman, Vanessa C. Irsik, Georg Jahn, Frank Jäkel, Marc Jekel, Magnus Johannesson, Larissa G. Johnson, David J. Johnson, Kate M. Johnson, William J. Johnston, Kai Jonas, Jennifer A. Joy-Gaba, Heather Barry Kappes, Kim Kelso, Mallory C. Kidwell, Seung Kyung Kim, Matthew Kirkhart, Bennett Kleinberg, Goran Knežević, Franziska Maria Kolorz, Jolanda J. Kossakowski, Robert Wilhelm Krause, Job Krijnen, Tim Kuhlmann, Yoram K. Kunkels, Megan M. Kyc, Calvin K. Lai, Aamir Laique, Daniël Lakens, Kristin A. Lane, Bethany Lassetter, Ljiljana B. Lazarević, Etienne P. LeBel, Key Jung Lee, Minha Lee, Kristi Lemm, Carmel A. Levitan, Melissa Lewis, Lin Lin, Stephanie Lin, Matthias Lippold, Darren Loureiro, Ilse Luteijn, Sean Mackinnon, Heather N. Mainard, Denise C. Marigold, Daniel P. Martin, Tylar Martinez, E.J. Masicampo, Josh Matacotta, Maya Mathur, Michael May, Nicole Mechin, Pranjal Mehta, Johannes Meixner, Alissa Melinger, Jeremy K. Miller, Mallorie Miller, Katherine Moore, Marcus Möschl, Matt Motyl, Stephanie M. Müller, Marcus Munafo, Koen I. Neijenhuijs, Taylor Nervi, Gandalf Nicolas, Gustav Nilsonne, Brian A. Nosek, Michèle B. Nuijten, Catherine Olsson, Colleen Osborne, Lutz Ostkamp, Misha Pavel, Ian S. Penton-Voak, Olivia Perna, Cyril Pernet, Marco Perugini, R. Nathan Pipitone, Michael Pitts, Franziska Plessow, Jason M. Prenoveau, Rima-Maria Rahal, Kate A. Ratliff, David Reinhard, Frank Renkewitz, Ashley A. Ricker, Anastasia Rigney, Andrew M. Rivers, Mark Roebke, Abraham M. Rutchick, Robert S. Ryan, Onur Sahin, Anondah Saide, Gillian M. Sandstrom, David Santos, Rebecca Saxe, René Schlegelmilch, Kathleen Schmidt, Sabine Scholz, Larissa Seibel, Dylan Faulkner Selterman, Samuel Shaki, William B. Simpson, H. Colleen Sinclair, Jeanine L. M. Skorinko, Agnieszka Slowik, Joel S. Snyder, Courtney Soderberg, Carina Sonnleitner, Nick Spencer, Jeffrey R. Spies, Sara Steegen, Stefan Stieger, Nina Strohminger, Gavin B. Sullivan, Thomas Talhelm, Megan Tapia, Anniek te Dorsthorst, Manuela Thomae, Sarah L. Thomas, Pia Tio, Frits Traets, Steve Tsang, Francis Tuerlinckx, Paul Turchan, Milan Valášek, Anna E. van ‘t Veer, Robbie Van Aert, Marcel van Assen, Riet van Bork, Mathijs van de Ven, Don van den Bergh, Marije van der Hulst, Roel van Dooren, Johnny van Doorn, Daan R. van Renswoude, Hedderik van Rijn, Wolf Vanpaemel, Alejandro Vásquez Echeverría, Melissa Vazquez, Natalia Velez, Marieke Vermue, Mark Verschoor, Michelangelo Vianello, Martin Voracek, Gina Vuu, Eric-Jan Wagenmakers, Joanneke Weerdmeester, Ashlee Welsh, Erin C. Westgate, Joeri Wissink, Michael Wood, Andy Woods, Emily Wright, Sining Wu, Marcel Zeelenberg, Kellylynn Zuni

A new computer program can predict who is at risk for psychotic episode(s) — by examining speech patterns — from among people apparently already aware that they may be mentally ill — and who are relatively close in time to manifesting their illness — says a study that examined 34 people, 5 of whom later developed psychotic breaks

© Peter Free

Citation — to study

Gillinder Bedi, Facundo Carrillo, Guillermo A Cecchi, Diego Fernández Slezak, Mariano Sigman, Natália B Mota, Sidarta Ribeiro, Daniel C Javitt, Mauro Copelli, and Cheryl M Corcoran, Automated analysis of free speech predicts psychosis onset in high-risk youths, NPJ [Nature Partner Journals] Schizophrenia 1: 15030, DOI: 10.1038/npjschz.2015.30 (26 August 2015)

Citation — to press release

Office of Communications, Who Will Develop Psychosis? Automated Speech Analysis May Have the Answer, Columbia University Medical Center (26 August 2015)

A helpful predictive aid?

From the abstract — my underline added:

In this proof-of-principle study, our aim was to test automated speech analyses combined with Machine Learning to predict later psychosis onset in youths at clinical high-risk (CHR) for psychosis.

Thirty-four CHR youths (11 females) had baseline interviews and were assessed quarterly for up to 2.5 years; five transitioned to psychosis.

Using automated analysis, transcripts of interviews were evaluated for semantic and syntactic features predicting later psychosis onset.

Speech features were fed into a convex hull classification algorithm with leave-one-subject-out cross-validation to assess their predictive value for psychosis outcome. The canonical correlation between the speech features and prodromal symptom ratings was computed.

Derived speech features included a Latent Semantic Analysis measure of semantic coherence and two syntactic markers of speech complexity: maximum phrase length and use of determiners . . . .

These speech features predicted later psychosis development with 100% accuracy, outperforming classification from clinical interviews. Speech features were significantly correlated with prodromal symptoms.

Findings support the utility of automated speech analysis to measure subtle, clinically relevant mental state changes in emergent psychosis. Recent developments in computer science, including natural language processing, could provide the foundation for future development of objective clinical tests for psychiatry.

© 2015 Gillinder Bedi, Facundo Carrillo, Guillermo A Cecchi, Diego Fernández Slezak, Mariano Sigman, Natália B Mota, Sidarta Ribeiro, Daniel C Javitt, Mauro Copelli, and Cheryl M Corcoran, Automated analysis of free speech predicts psychosis onset in high-risk youths, NPJ [Nature Partner Journals] Schizophrenia 1: 15030, DOI: 10.1038/npjschz.2015.30 (26 August 2015) (at Abstract) (extracts, underline added)

Notice the essentially self-selected sample population

From the paper’s Materials and Methods: Participants section:

Participants were 34 help-seeking youths aged 14 to 27 years who were fluent in English . . . .

They were referred from schools and clinicians, or self-referred through the Center of Prevention and Evaluation website.

Exclusion criteria included history of threshold psychosis or Axis I psychotic disorder, risk of harm to self or others incommensurate with outpatient care, any major medical or neurological disorder, and Intelligence Quotient<70 . . . .

The attenuated psychotic symptoms characteristic of the CHR [clinical high risk] participants could not have occurred solely in the context of substance use or withdrawal.

© 2015 © 2015 Gillinder Bedi, Facundo Carrillo, Guillermo A Cecchi, Diego Fernández Slezak, Mariano Sigman, Natália B Mota, Sidarta Ribeiro, Daniel C Javitt, Mauro Copelli, and Cheryl M Corcoran, Automated analysis of free speech predicts psychosis onset in high-risk youths, NPJ [Nature Partner Journals] Schizophrenia 1: 15030, DOI: 10.1038/npjschz.2015.30 (26 August 2015) (at section entitled Participants) (extracts)

Consider how soon after the start of the study, the detected patients became ill

From the Results section of the paper:

Of the 34 participants, 5 were known to develop schizophrenia (or schizoaffective disorder) within 2.5 years.

Respectively, their times to psychosis onset from time of speech sampling were 3, 4, 8, 12, and 16 months.

Twenty-nine participants were known to not develop psychosis over follow-up, with 22 of these participants followed for 2.5 years, 4 participants followed for 2 years, and 3 followed for 1.5 years . . . .

An additional participant’s transcript was not included in speech analyses because her clinical outcome was indeterminate; she remained psychosis-free over 1.5 years of follow-up, but may have subsequently developed psychosis after the study.

© 2015 © 2015 © 2015 Gillinder Bedi, Facundo Carrillo, Guillermo A Cecchi, Diego Fernández Slezak, Mariano Sigman, Natália B Mota, Sidarta Ribeiro, Daniel C Javitt, Mauro Copelli, and Cheryl M Corcoran, Automated analysis of free speech predicts psychosis onset in high-risk youths, NPJ [Nature Partner Journals] Schizophrenia 1: 15030, DOI: 10.1038/npjschz.2015.30 (26 August 2015) (at section entitled Results: CHR analysis) (paragraph split)

Caveats

The team recognizes that their sample was small and their results need replication.

I would explicitly add also that people who:

(a) know they are (or may be) ill

and

(b) are willing to seek help —

may differ from those who exhibit neither trait.

This study, even if corroborated among the same kind of sub-population, demonstrates only that computerized language delivery detection is useful in:

(a) self-referred patients

(b) in a relatively narrow age range

and

(c) not too long before they experience their psychotic episodes.

Which presumably leaves the bulk of the potentially severely mentally ill still “out there”, unaided.

The moral? — Striking concept, apparently very well executed — and obviously potentially useful in some significant instances

More reliably predicting psychotic episodes would (indeed) be dramatically helpful.

We just should not lose sight of the probable unrepresentativeness of this study’s numerically small and trait-restricted sample population.

Nevertheless, despite the above caveats, I am impressed.

Traces of active ebola virus may survive in wastewater for more than 8 days — says a study with significant and wisely pointed out limitations

© 2015 Peter Free

Citation — to study

Kyle Bibby, Robert J. Fischer, Leonard W. Casson, Elyse Stachler, Charles N. Haas, and Vincent J. Munster, Persistence of Ebola Virus in Sterilized Wastewater, Environmental Science & Technology Letters, DOI: 10.1021/acs.estlett.5b00193 (just accepted manuscript, 17 August 2015)

Citation — to press release

Joe Miksch, Pitt, Drexel, and NIH Team up to Study Persistence of Ebola Virus in Wastewater, University of Pittsburgh (25 August 2015)

Background — the potential public health problem that the team wanted to investigate

From the open access paper’s Introduction:

In March 2014, an unprecedented outbreak of Ebola virus disease (EVD) began in Western Africa that as of July 2015 is ongoing and has claimed more than 11000 lives. The current outbreak is caused by viruses belonging to the species of the Zaire ebolavirus, a member of the Filoviridae family.

The current outbreak has a reported case fatality rate of 51%.

Ebola virus can be excreted in bodily fluids, including vomit, stool, blood, saliva, semen, and breast milk.

The median infectious dose is believed to be <10 infectious viral particles.

Once infected, individuals may produce up to 9 L of liquid waste per day, primarily watery diarrhea. Ebola virus is considered a potential bioterrorism agent.

In response to the EVD epidemic, both the World Health Organization (WHO) and the U.S. Centers for Disease Control and Prevention advised direct disposal of Ebola-contaminated liquid waste into sewage systems . . . and latrines without disinfection.

However . . . the persistence of enveloped viruses in the water environment varies by >2 orders of magnitude. Recommendations for Ebola virus-contaminated wastewater disposal were met with debate . . . because of uncertainty about Ebola virus persistence within wastewater matrices and the lack of a risk-based analysis for waste handling.

Wastewater handling recommendations have since been revised to recognize uncertainty in this area and to recommend disinfection of latrines and holding of wastewater prior to handling to allow Ebola virus inactivation.

© 2015 Kyle Bibby, Robert J. Fischer, Leonard W. Casson, Elyse Stachler, Charles N. Haas, and Vincent J. Munster, Persistence of Ebola Virus in Sterilized Wastewater, Environmental Science & Technology Letters, DOI: 10.1021/acs.estlett.5b00193 (just accepted manuscript, 17 August 2015) (at Introduction) (extracts)

Method and findings

The team put ebola virus into sterilized sewage water safely contained inside a biosafety laboratory. Then they measured how long it took the virus load to die out. Between 90 and 90 percent of the virus load dies within the first day or two. However traces of still active virus remained at the end of the 8 day experiment.

Caveats

These are significant, as the research team alertly pointed out:

First, the tested wastewater was more dilute than would be expected in typical latrine waste. In general, interaction with constituents within the wastewater (e.g., ammonia) would be expected to contribute to more rapid inactivation of viruses; however, the true effect of these constituents on Ebola virus persistence is unknown.

Second, the wastewater was frozen to minimize compositional changes and disinfected (γ-irradiation) prior to utilization to limit microbial activity resulting in false positive viral cell culture. Microbial activity within wastewater matrices would be expected to contribute to more rapid inactivation of infectious viral particles; however, the true effect of microbial activity on Ebola virus persistence is unknown.

Microbial activity reduces viral persistence through both the production of metabolites detrimental to viral persistence and direct usage of the viral particles as a nutrient source. Additionally, the influence of other environmental characteristics (e.g., temperature, pH, and mixing) on Ebola virus persistence is unknown and may contribute to altered environmental behavior.

As such, we believe these results to be an upper bound for Ebola virus persistence in wastewater matrices.

Subsequently, we caution extrapolation of these results without a holistic assessment of all factors, including wastewater composition, dilution, and potential exposure routes.

© 2015 © 2015 Kyle Bibby, Robert J. Fischer, Leonard W. Casson, Elyse Stachler, Charles N. Haas, and Vincent J. Munster, Persistence of Ebola Virus in Sterilized Wastewater, Environmental Science & Technology Letters, DOI: 10.1021/acs.estlett.5b00193 (just accepted manuscript, 17 August 2015) (at Limitations) (paragraph split)

The moral? — Further research is necessary

Given the plethora of complicating variables with regard to ebola and sewage, we still do not know whether prevailing field disposal techniques are adequate.

The equatorial electrojet — amplifies the electromagnetic effects of comparatively insignificant space weather — to potentially power infrastructure-disrupting levels

© 2015 Peter Free

Citation — to study

A. Carter, E. Yizengaw, R. Pradipta, A. J. Halford, R. Norman, and K. Zhang, Interplanetary shocks and the resulting geomagnetically induced currents at the equator, Geophysical Research Letters, DOI: 10.1002/2015GL065060 (pre-print manuscript, 06 August 2015)

Citation — to press release

Ed Hayward, New Study Finds Equatorial Regions Prone to Disruptive Space Weather, Boston College (24 August 2015) (with diagram of the equatorial electrojet)

Location evidently makes a difference

From the abstract:

Geomagnetically induced currents (GICs) caused by interplanetary shocks represent a serious space weather threat to modern technological infrastructure.

The arrival of interplanetary shocks drives magnetosphere and ionosphere currents systems, which then induce electric currents at ground level. The impact of these currents at high latitudes has been extensively researched, but the magnetic equator has been largely overlooked.

In this paper, we investigate the potential effects of interplanetary shocks on the equatorial region and demonstrate that their magnetic signature is amplified by the equatorial electrojet.

This local amplification substantially increases the region’s susceptibility to GICs. Importantly, this result applies to both geomagnetic storms and quiet periods, and thus represents a paradigm shift in our understanding of adverse space weather impacts on technological infrastructure.

© 2015 B. A. Carter, E. Yizengaw, R. Pradipta, A. J. Halford, R. Norman, and K. Zhang, Interplanetary shocks and the resulting geomagnetically induced currents at the equator, Geophysical Research Letters, DOI: 10.1002/2015GL065060 (06 August 2015) (at Abstract) (paragraph split)

In further explanation

From the press release:

[Brett] Carter and his team . . . examine the effects of interplanetary shocks in the solar wind, which is the stream of charged particles that flows out of the Sun.

Massive explosions on the Sun’s surface can cause these shocks, but many are created through far less violent means.

Analyzing 14 years of data collected in space and on Earth, the team found that geomagnetically induced currents are amplified by the equatorial electrojet, a naturally occurring flow of current approximately 100 kilometers above the surface of the Earth.

Wending its way through the Earth’s ionosphere along the magnetic equator, the electrojet travels above large swaths of Africa, South America, Southeast Asia and the southern tip of India.

These equatorial electrical disruptions – fueled by geomagnetically induced currents – pose a threat to power grids in countries where shielding electricity infrastructure from space shocks has not been a recognized priority.

[E]lectrical disruptions in the equatorial region do not require severe geomagnetic storms, similar in scale to events that have crashed [more northern] power grids in the past, most notably in Quebec in 1989 and in Sweden in 2003.

© 2015 Ed Hayward, New Study Finds Equatorial Regions Prone to Disruptive Space Weather, Boston College (24 August 2015) (reordered extracts)

The moral? — It’s always something

Our planet’s dynamic intricacies are exceedingly interesting, even when the power goes out.