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A new study of Danish farmers and their livestock uses genetic sequencing to show that antibiotic-resistant bacterial infections travel from animal to human. Maryn McKenna describes the evidence. 
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Phillip Trotter's insight:
Interesting article by Rick Lewis on PLOS comparing evolution of CAT Feline, Simian and Human immunodeficiency virus oras they are better known FIV, SIV and HIV. SIV no longer sickens most wild primates because they’ve had 12 million years to adapt. Cat species around for a long time, like lions, are less likely to get sick from FIV than their more modern relatives, such as our domesticated friends. These trends give an interesting view of HIV evolution i terms of its long term possible pathways and how that relates to potential treatments and health policy. Worth reading and thinking about. Click on title or image to learn more.
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Hantaviruses cause hemorrhagic fever with renal syndrome (HFRS) in Eurasia. In Europe both the amplitude and the magnitude of outbreaks of HFRS have increased. The mechanisms that drive the incidences are complex and multi-factorial and only partially due to increased awareness and improved diagnostic tools. Risk determinants include reservoir ecology, virus ecology and anthropogenic factors. The dogma of one specific rodent species as primordial reservoir for a specific hantavirus is increasingly challenged. New hantaviruses have been discovered in shrews, moles and bats and increasing evidence points at host-switching events and co-circulation in multiple, sympatric reservoir species, challenging the strict rodent–virus co-evolution theory. Changing landscape attributes and climatic parameters determine fluctuations in hantavirus epidemiology, for instance through increased food availability, prolonged virus survival and decreased biodiversity.
Via Ed Rybicki
Ed Rybicki's curator insight,
March 7, 2013 12:58 AM
There WILL be more of this: and viruses that were curiosities of teh developing world, will suddenly get attention from the more monied countries. And hopefully, vaccines too.
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Health officials in the UK believe they have the strongest evidence yet that a new respiratory illness similar to the deadly Sars virus can spread from person to person.
Phillip Trotter's insight:
BBC is is reporting that UK health officials believe Coronavirus can spread between species and potentially between humans in close contact with one another. While there are concerns about the new Corona virus since it is from the same family that produce the common cold, generally experts consider it another respitory infection and at this point there is no worry concern over potential pandemic due to the very small number of cases involved.
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Antiviral resistance in influenza is rampant and has the possibility of causing major morbidity and mortality. Previous models have identified treatment regimes to minimize total infections and keep resistance low. However, the bulk of these studies have ignored stochasticity and heterogeneous contact structures. Here we develop a network model of influenza transmission with treatment and resistance, and present both standard mean-field approximations as well as simulated dynamics. We find differences in the final epidemic sizes for identical transmission parameters (bistability) leading to different optimal treatment timing depending on the number initially infected. We also find, contrary to previous results, that treatment targeted by number of contacts per individual (node degree) gives rise to more resistance at lower levels of treatment than non-targeted treatment. Finally we highlight important differences between the two methods of analysis (mean-field versus stochastic simulations), and show where traditional mean-field approximations fail. Our results have important implications not only for the timing and distribution of influenza chemotherapy, but also for mathematical epidemiological modeling in general. Antiviral resistance in influenza may carry large consequences for pandemic mitigation efforts, and models ignoring contact heterogeneity and stochasticity may provide misleading policy recommendations. Via Ashish Umre, Eugene Ch'ng
Phillip Trotter's insight:
This is an important piece of research for disease modeling and stochastic simulations versus mean field approaches. If disease modeling or health systems are in your interest area this is a must read. Click on image or title to learn more.
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Social network analysis is now widely used to investigate the dynamics of infectious disease spread from person to person. Vaccination dramatically disrupts the disease transmission process on a contact network, and indeed, sufficiently high vaccination rates can disrupt the process to such an extent that disease transmission on the network is effectively halted. Here, we build on mounting evidence that health behaviors - such as vaccination, and refusal thereof - can spread through social networks through a process of complex contagion that requires social reinforcement. Using network simulations that model both the health behavior and the infectious disease spread, we find that under otherwise identical conditions, the process by which the health behavior spreads has a very strong effect on disease outbreak dynamics. This variability in dynamics results from differences in the topology within susceptible communities that arise during the health behavior spreading process, which in turn depends on the topology of the overall social network. Our findings point to the importance of health behavior spread in predicting and controlling disease outbreaks.
Complex social contagion makes networks more vulnerable to disease outbreaks Ellsworth Campbell, Marcel Salathé http://arxiv.org/abs/1211.0518 Via Complexity Digest
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The full lecture title is "Cancers - Their Genomes, Microenvironments, and Susceptibility to Bacteria-based Therapies" by Bert Vogelstein. The Johns Hopkins Center for Biotechnology Education and the Department of Biology in the Krieger School of Arts and Sciences hosted the American Society for Microbiology's Conference for Undergraduate Educators (ASMCUE) on the Homewood campus. Bert Vogelstein gave the closing plenary lecture, "Cancers - Their Genomes, Microenvironments, and Susceptibility to Bacteria-based Therapies". He teaches at John Hopkins University. Via Dr. Stefan Gruenwald
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Background
Papillomavirus graphic by Russell Kightley Media
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Methamphetamine (meth) is a highly addictive psychostimulant that is among the most widely abused illicit drugs, with an estimated over 35 million users in the world. Several lines of evidence suggest that chronic meth abuse is a major factor for increased risk of infections with human immunodeficiency virus and possibly other pathogens, due to its immunosuppressive property. Influenza A virus infections frequently cause epidemics and pandemics of respiratory diseases among human populations. However, little is known about whether meth has the ability to enhance influenza A virus replication, thus increasing severity of influenza illness in meth abusers. Herein, we investigated the effects of meth on influenza A virus replication in human lung epithelial A549 cells.
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Very interesting article on filoviruses in Popular Science from David Quammen's new book, Spillover . Style of the article reminded me a lot of Richard Preston's excellent The Hot Zone (1994) and covers similar territory with more upto date insight, information and examples including the background to the 2008 CCD, WHO amd NICD paper on discovery of Marbug virus reservour n a large fruit bat Colony in Uganda.
The dangers presented by zoonoses (transferance of animal disease to humans) are real and severe, but the degree of uncertainties is also high. Too many factors vary randomly, or almost randomly, in that system. Prediction, in general, so far as all these diseases are concerned, is a tenuous proposition, more likely to yield false confidence than actionable intelligence. The practical alternative to soothsaying, as one expert put it, is “improving the scientific basis to improve readiness.” By “the scientific basis” he meant the understanding of which virus groups to watch, the field capabilities to detect spillovers in remote places before they become regional outbreaks, the organizational capacities to control outbreaks before they become pandemics, plus the laboratory tools and skills to recognize known viruses speedily, to characterize new viruses almost as fast, and to create vaccines and therapies without much delay. If we can’t predict a forthcoming influenza pandemic or any other newly emergent virus, we can at least be vigilant; we can be well prepared and quick to respond; we can be ingenious and scientifically sophisticated in the forms of our response. Good article and Quammen's book is on the must read list for this year. Learn more by clicking on the image or the title for more information.
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From the World Health Organization Health Bulletin: As public and political awareness of emerging infectious diseases is growing, as animal and human health specialists work closer together to avert potential outbreaks. More than 30 new human infectious diseases have emerged over the past three decades, most of them originating in the animal world. The “One Health” movement is about preventing situations such as deforestation and certain agricultural practices that encourage their emergence, and it advocates for early detection.There are still huge gaps in our knowledge, we need a better understanding of the wildlife hosts of pathogens, otherwise we will not be able to prevent future outbreaks,” says Linfa Wang who heads the emerging virus research team at the CSIRO Australian Animal Health Laboratory. In 2009, the United States government launched the Emerging Pandemic Threats programme to “preempt or combat diseases that could cause future pandemics”. It works in partnership with the World Health Organization (WHO), the United Nations Food and Agriculture Organization (FAO) and the World Organization for Animal Health (OIE) to help develop laboratory networks and strengthen diagnostic capacities in the places where new diseases occur. “If we’d had these systems 50 years ago, perhaps we could have detected HIV (the virus that causes AIDS) and averted the pandemic that has killed millions of people.” says Pierre Formenty, who leads the Emerging and Dangerous Pathogens team at the World Health Organization in Geneva Switzerland. To learn more - click on the image or the title.
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Lethal mutagenesis or virus transition into error catastrophe is an antiviral strategy that aims at extinguishing a virus by increasing the viral mutation rates during replication. The molecular basis of lethal mutagenesis is largely unknown. Previous studies showed that a critical substitution in the foot-and-mouth disease virus (FMDV) polymerase was sufficient to allow the virus to escape extinction through modulation of the transition types induced by the purine nucleoside analogue ribavirin. This substitution was not detected in mutant spectra of FMDV populations that had not replicated in the presence of ribavirin, using standard molecular cloning and nucleotide sequencing. Here we selectively amplify and analyze low-melting-temperature cDNA duplexes copied from FMDV genome populations passaged in the absence or presence of ribovirin Hypermutated genomes with high frequencies of A and U were present in both ribavirin -treated and untreated populations, but the major effect of ribavirin mutagenesis was to accelerate the occurrence of AU-rich mutant clouds during the early replication rounds of the virus. Click on the image or title to learn more.
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Genetically modified (GM) mosquitoes released into the environment... reduced the population of dengue-carrying Aedes aegypti mosquitoes by 80 per cent, according to a study... another successful trial of GM mosquitoes in Juazeiro region, Brazil, where a controlled release of GM A. aegypti reduced the mosquito population in the region by 90 per cent... Constância Ayres, a researcher from the department of entomology at Fiocruz Pernambuco, a Brazilian research institute, believes the method is safe. "It is not a transgene [a transferred gene] that will remain in nature. It sterilises offspring, so it has no role in the epidemiology of the disease. The gene will not persist in the environment"... "I believe this is a promising tool, but we are a long way from using it in nationwide control programmes. Production [of GM mosquitoes] is still a limiting factor"... "This tool could be added to a well-established control programme — for instance when you need to momentarily suspend the use of insecticides, you would have another option"... The WHO estimates that 50 to 100 million dengue infections occur each year, causing 500,000 cases of dengue haemorrhagic fever and 22,000 deaths, mostly among children. Via Alexander J. Stein
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Plans to tackle tuberculosis are failing and a new visionary approach is needed, according to an international group of doctors and scientists.
Phillip Trotter's insight:
In Eastern europe up to a third of TB ccases are multi-drug resitant and a more extensively drug resistant form of tuberculosis has now been found in 84 countries. Scary set of implications given rate of evolution of multiresistant strains.
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On the heels of the director of the US Centers for Disease Control declaring emerging antibiotic resistance a "nightmare," the UK's Chief Medical Officer released a report in which she calls resistance a "catastrophic threat" that poses a national...
Phillip Trotter's insight:
Wired has a good summary article on the U.K.’s Chief Medical Officer report on microbial resistance in which she calls resistance a “catastrophic threat” which poses a national security risk as serious as terrorism. In an interview published overnight, she warns that unless resistance is curbed, “We will find ourselves in a health system not dissimilar to the early 19th century” in which organ transplants, cancer chemotherapy, joint replacements and even minor surgeries become life-threatening. Click on the image or title to get the Wired article summarizing the report or read the report in full: http://bit.ly/XCKdXQ ;
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It's not normal for a top federal health official to deploy a word such as "nightmare," or warn: "We have a very serious problem, and we need to sound an alarm." But on Tuesday, the director the CDC said both during a press conference about the...
Phillip Trotter's insight:
Public reaction to news of antibiotic resistance seems to follow a predictable pattern: Instant alarm, followed almost immediately by apathy as the daily routine re-inserts itself. It will be interesting seeing how these announcements are covered and discussed and wether or not consideration of alternate mechanisms, and understanding of adaptation, evolution and bacterial communication enter the discussions more widely. Click on the title or the image to learn more..
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Phillip Trotter's insight:
Hantaviruses are among the most important zoonotic pathogens of humans and the subject of heightened global attention. Despite the importance of hantaviruses for public health, there is no consensus on their evolutionary history and especially the frequency of virus-host co-divergence versus cross-species virus transmission. Documenting the extent of hantavirus biodiversity, and particularly their range of mammalian hosts, is critical to resolving this issue and something this paper focuses on. Well worth reading in relation to public health planning and disease modeling and understanding how interconnected our health biome actually is.
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Throughout North America, honeybees are abandoning their hives. The workers are often found dead, some distance away. Meanwhile, the hives are like honeycombed Marie Celestes, with honey and pollen left uneaten, and larvae still trapped in their chambers.
There are many possible causes of this “colony collapse disorder” (CCD). These include various viruses, a single-celled parasite called Nosema apis, a dramatically named mite called Varroa destructor, exposure to pesticides, or a combination of all of the above. Any or all of these factors could explain why the bees die, but why do the workers abandon the hive?
Andrew Core from San Francisco State University has a possible answer, and a new suspect for CCD. He has shown that a parasitic fly, usually known for attacking bumblebees, also targets honeybees. The fly, Apocephalus borealis, lays up to a dozen eggs in bee workers. Its grubs eventually eat the bees from the inside-out. And the infected workers, for whatever reason, abandon their hives to die.
There are hundreds of species of Apocephalus flies, and they’re best known for decapitating ants from the inside. The larvae, laid within an ant, migrate to the head and devour the tissue inside. The brainless ant wanders aimlessly for weeks, before the larvae release an enzyme that dissolves the connection between the ant’s head and body. The head falls off, and adult flies emerge from it.
A. borealis has a similar modus operandi, but it targets bees not ants. Core discovered its penchant for honeybees by sampling workers that had been stranded in the lights of his faculty building, and other locations throughout the San Francisco Bay area. The fly was everywhere. It was parasitizing bees in three-quarters of the places that Core studied, and its DNA confirmed that the species that attacked honeybees was the same one that kills bumblebees.
When Core exposed honeybees to the flies in his lab, he saw the same events that befall unfortunate ants. The flies lay eggs in a bee’s body and weeks later, larvae burst out from behind the insect’s head. It’s no surprise that the infected bees, with up to 13 larvae feasting on their brains, seem a little disoriented. They walk round like zombies, pacing in circles and often unable to stand up.
They also abandon their hives. Core found that the dying insects literally head towards the light. Large numbers of them become stranded within bright lights. Many flying insects show a similar attraction, but the stranded bees were stock still rather than buzzing about. They would also head towards lights on cold, rainy nights when other insects seek shelter. Via Dr. Stefan Gruenwald, Robin Lott
Phillip Trotter's insight:
Awesome catch by Robin Lott and a good article.
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Influenza recurs seasonally in temperate regions of the world; however, our ability to predict the timing, duration, and magnitude of local seasonal outbreaks of influenza remains limited. Here we develop a framework for initializing real-time forecasts of seasonal influenza outbreaks, using a data assimilation technique commonly applied in numerical weather prediction. The availability of real-time, web-based estimates of local influenza infection rates makes this type of quantitative forecasting possible. Retrospective ensemble forecasts are generated on a weekly basis following assimilation of these web-based estimates for the 2003–2008 influenza seasons in New York City. The findings indicate that real-time skillful predictions of peak timing can be made more than 7 wk in advance of the actual peak. In addition, confidence in those predictions can be inferred from the spread of the forecast ensemble. This work represents an initial step in the development of a statistically rigorous system for real-time forecast of seasonal influenza.
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Ebola viruses (EBOV) cause often fatal hemorrhagic fever in several species of simian primates including human. While fruit bats are considered natural reservoir, involvement of other species in EBOV transmission is unclear. Recent findings from pig to simian transfer indicate that natural reservoirs may be in multiple places. Click on the image or the title to learn more.
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“The survey is currently in its first phase and is a door-to-door exercise. As of Monday, we surveyed 3,55,959 homes. Of them, 13,367 have been found to have larvae,” Dr Devaki told Express.
She added that every house that had dengue larvae was marked as D+. “We did this so that in the second phase of the survey we can concentrate only on D+ homes,” she said.
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In Search of Spanish Flu 2 of 2 - BBC Science Documentary, recorded 03.04.2009 Documentary in which a team of top UK virologists exhume the body of statesman...
And again: Ken Yaw Agyeman Badu, many thanks! Via Ed Rybicki
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Over the years, researchers in the laboratory of ETH-professor Ari Helenius have elucidated the tricks and tactics viruses use to enter human cells and exploit them for their own multiplication and spread. Jason Mercer, in a collaboration with Berend Snijder and colleagues from the Universtiy of Zürich have just released a publication which puts forward new insights into how viruses enter human cells. "For the first time we were able to demonstrate a mechanism by which a virus uses the cellular waste-disposal system to facilitate release of the viral DNA, which is subsequently multiplied, and used for the formation of new virus particles" he says. In addition, the researchers were able to block the release of viral DNA – using a drug which is already approved for human use. Complete protein inventory During infection, viruses communicate with the host cell and they "abuse" a specific set of host proteins to assist them during their life-cycle. In collaboration with the group of University Professor Lukas Pelkmans, Jason Mercer set out to identify the cellular proteins which the vaccinia virus requires. The idea being that this knowledge may be helpful when developing new strategies to stop infection Click on the image, or the title or read more at: http://phys.org/news/2012-10-virus-exploitscellular-disposal.html#jCp
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A deadly form of Salmonella has swept through Africa in the wake of the spread of HIV, according to an international team of researchers. t is thought to be the first time a single strain of an infection has spread so widely in the wake of HIV. Cases of this form of invasive non-typhoidal Salmonella have been recognised in Africa for more than a decade. It causes fever, headaches, respiratory problems and sometimes death. "It quite clearly parallels the emergence of HIV in Africa” said Prof Gordon Dougan of the Sanger Institute. The research team analysed the genetic code of 179 batches of Salmonella from different parts of Africa and the rest of the globe. Using techniques similar to a large-scale DNA paternity test, they were able to construct the strain's "family tree" and then how it spread. Click the image or the title ot learn more.
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Researchers find the source of an epidemic using relatively little information. Their technique could also help authorities track down contamination in water systems or locate problems in electrical grids. Via Frédéric Amblard
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Another awesome article by Maryn McKenna. If the analysis presented in the article is correct, then it indicates several sources of potential trouble. The article highlights potential for animal-to-human transmission of resistant bacteria even by animals that are not routinely receiving antibiotics. Finally the potential host range for resitant bacteria that is, the species detected to be carrying mecCMRSA, now mostly being called CC130 extends past farm breeds to include host range to include not just cows and sheep, but horses, rabbits, cats, dogs, deer, seals, rats and wild birds. Worth reading the entire article so click on the image or the title to learn more.