Cornering multiple sclerosis -- still a long way to go

Multiple sclerosis is an autoimmune disease of the central nervous system that causes neurological disability in young adults. Several environmental and genetic factors have been linked to the disease, but the precise mechanisms involved, and whether neurological damage precedes inflammation or vice versa, remain unclear.

In a recent article published in Nature, an international consortium of researchers report the identification of 29 new susceptibility loci, most of which are related to immune system function and, in particular, to T-helper-cell differentiation.

Previous genome-wide association studies (GWAS) that analysed relatively modest numbers of multiple sclerosis patients identified more than 20 risk loci, especially some that encode components of the major histocompatibility complex (MHC). To identify a more complete set of susceptibility loci and obtain new insights into disease mechanisms, an international team of researchers carried out a large GWAS in which they analyzed over 465,000 autosomal single nucleotide polymorphisms (SNPs) from about 9,800 patients and 17,400 controls (that is, people not affected by multiple sclerosis) from 15 countries.

This analysis confirmed 23 loci that had previously been linked to the disease, and revealed another 29 new loci. Most of the risk attributable to the MHC could be accounted by four mutations, one in class-I locus HLA-A and three in class-II locus HLA-DRB1.

A statistical analysis of the functions of the 52 loci (as annotated in the Gene Ontology database) showed that they are enriched for lymphocyte functions. In particular, many genes encoding cell surface receptors (such as CXCR5 and IL7R) with roles in T-helper-cell differentiation showed strong association with multiple sclerosis. In addition, the researchers identified two susceptibility loci with a role in vitamin D synthesis (CYP27B1 and CYP24A1) and others that encode known targets of therapies for multiple sclerosis such as natalizumab (VCAM1) and daclizumab (IL2RA). By contrast, very few genes with known roles in inflammation-independent neurodegeneration were identified.

The overrepresentation of susceptibility genes with roles in T-cell maturation suggests that multiple sclerosis is primarily caused by immune dysfunction, which is followed by neurological damage. However, the 52 variants can explain only ~20% of the heritability of the disease, and therefore a myriad of other susceptibility loci, each adding a tiny percentage to the overall risk of developing multiple sclerosis, remain to be identified.


Original article:
The International Multiple Sclerosis Genetics Consortium & The Wellcome Trust Case Control Consortium 2 (2011). Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis Nature, 476 (7359), 214-219 DOI: 10.1038/nature10251


The same story in the news:
- Study identifies 57 genes linked with MS, Multiple Sclerosis Society, UK (10 Aug 2011).
- Multiple sclerosis genes identified in largest-ever study of the disease by Alok Jha, The Guardian (10 Aug 2011).
- Scientists unravel genetic clues to multiple sclerosis by Kate Kelland, Reuters (10 Aug 2011).


Note:
During the last 10 months, I have written 18 Research Highlights (short pieces of 300-400 words that summarize recent scientific articles) for Nature Reviews Microbiology. This blog post is based on my first attempt to write a similar piece about a non-microbiological article. However, to make the post more 'blog-friendly', I have embedded some links to definitions of key terms. You can read the definitions by rolling your mouse over the highlighted terms, or you can click on the term to visit a website with more information. Also, I have added a couple of links to news articles that covered the same story.

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TED videos: excellent talks about life, the universe and everything -- including microbes

TED is a nonprofit organization devoted to "ideas worth spreading." They are mostly known because of their growing collection of fascinating talks about a wide array of topics, including science, art and anything in-between (or around). The talks are recorded and the videos are freely available at their website, where you can also find information about the speakers and interactive transcripts (including translations to various languages).

In this post I'm collecting links to all the TED videos I could find related to the microbial world.

Topics include: life in the deep oceans, medical mysteries, bacterial Esperanto, predicting pandemics, robots turned into microbiologists, new approaches to handle infectious diseases, looking for life on Mars and beyond, fungi that could save the world, bacteria that may have caused mass extinctions...

Awesome, huh?

I'm also embedding a video for one of the latest TED talks: Seth Berkley: HIV and flu -- the vaccine strategy. The speaker, epidemiologist Seth Berkley, is the founder of the International AIDS Vaccine Initiative. In this talk, filmed last February, he spoke about new methods for making vaccines for AIDS and flu.





I also recommend reading this interview on the TED blog, where Seth Berkley commented on the same subject. I am copying here a few remarkable quotes:

I was very disappointed by public concerns that we ordered too much flu vaccine and that some might get wasted. (...) I think that both declaring this a global pandemic and accelerating vaccine production as quickly as possible were the right decisions. If you want to prepare a population for an emergency it means that you might ultimately spend some money that isn’t used.

That's a good point. Many criticisms have been raised in the last months against WHO decisions in relation to the recent flu pandemic. And some of those criticisms were undeserved, in my opinion.


In the interview, Berkley explained why so much effort was put on developing treatments --rather than preventive vaccines-- for AIDS. And he described the extraordinary work they're doing with the International AIDS Vaccine Initiative.


To the question "Are the members of the younger generation of scientists as invested in creating a vaccine as was the case 10 years ago or so?" he responded:

Sadly not. (...) The problem is not that young scientists don’t think vaccines are incredibly important, the problem is that it is seen as such a difficult problem, such a long-term problem that what they’re worried about is: Can they build a career on it? Can they get the types of breakthroughs they need in a rapid time frame that would make it a productive place to work?

It is disturbing that the "productivity" concept not only is doing harm to many researchers' careers but may also be slowing down the development of much-needed medical treatments...


Why not focus just on the treatment of infected people, and forget about an AIDS vaccine? Berkley explained:

(...) from a public policy point of view, there’s great expense involved in dealing with the epidemic through treatment and reaching people when they’re already infected. (...) But this is a long-term entitlement program, because once you put somebody on treatment, they have to get treatment for the rest of their lives and they develop conditions, they develop toxicity and they need other treatments. So, there’s almost a sense now that all of the bright lights of that unbelievable effort -- the unprecedented emergency program for AIDS relief, Bush’s triumph that people look on as being a great thing that he did, will create a demand that gets higher and higher and higher just to keep up with where we are.

So, making an effective vaccine against AIDS may be very difficult. But it is worth the effort.




And finally, as promised, this is the list of other TED videos related to the small living beings (in chronological order, newest first):


[Added October 15th, 2010 -- Eben Bayer: Are mushrooms the new plastic? "Product designer Eben Bayer reveals his recipe for a new, fungus-based packaging material that protects fragile stuff like furniture, plasma screens -- and the environment." July 2010. Found via MicrobiologyBytes.]

Magnus Larsson: Turning dunes into architecture. "Architecture student Magnus Larsson details his bold plan to transform the harsh Sahara desert using bacteria and a surprising construction material: the sand itself." July 2009.

Nathan Wolfe: hunting the next killer virus. "Virus hunter Nathan Wolfe is outwitting the next pandemic by staying two steps ahead: discovering deadly new viruses where they first emerge -- passing from animals to humans among poor subsistence hunters in Africa -- before they claim millions of lives." February 2009.

Bonnie Bassler: discovering bacteria's amazing communication system. "Bonnie Bassler discovered that bacteria "talk" to each other, using a chemical language that lets them coordinate defense and mount attacks. The find has stunning implications for medicine, industry -- and our understanding of ourselves." February 2009.

Hans Rosling on HIV: New facts and stunning data visuals. "Hans Rosling unveils new data visuals that untangle the complex risk factors of one of the world's deadliest (and most misunderstood) diseases: HIV. He argues that preventing transmissions -- not drug treatments -- is the key to ending the epidemic." February 2009.

Kary Mullis' next-gen cure for killer infections. "Drug-resistant bacteria kills, even in top hospitals. But now tough infections like staph and anthrax may be in for a surprise. Nobel-winning chemist Kary Mullis, who watched a friend die when powerful antibiotics failed, unveils a radical new cure that shows extraordinary promise." February 2009.

James Nachtwey fights XDR-TB. "Photojournalist James Nachtwey sees his TED Prize wish come true, as we share his powerful photographs of XDR-TB, a drug-resistant strain of tuberculosis that's touching off a global medical crisis. Learn how to help at http://www.xdrtb.org" October 2008.

Paul Stamets: six ways mushrooms can save the world. "Mycologist Paul Stamets lists 6 ways the mycelium fungus can help save the universe: cleaning polluted soil, making insecticides, treating smallpox and even flu." March 2008.

Peter Ward: Earth's mass extinctions. "Asteroid strikes get all the coverage, but "Medea Hypothesis" author Peter Ward argues that most of Earth's mass extinctions were caused by lowly bacteria. The culprit, a poison called hydrogen sulfide, may have an interesting application in medicine." February 2008.

Paul Ewald: can we domesticate germs? "Evolutionary biologist Paul Ewald drags us into the sewer to discuss germs. Why are some more harmful than others? How could we make the harmful ones benign? Searching for answers, he examines a disgusting, fascinating case: diarrhea.". March 2007. (I embedded this video in a previous post.)

Bill Stone explores the world's deepest caves. "Bill Stone, a maverick cave explorer who has plumbed Earth’s deepest abysses, discusses his efforts to mine lunar ice for space fuel and to build an autonomous robot for studying Jupiter’s moon Europa." "How do you take a robot and turn it into a field microbiologist?" March 2007.

Laurie Garrett on lessons from the 1918 flu. "In 2007, as the world worried about a possible avian flu epidemic, Laurie Garrett, author of "The Coming Plague," gave this powerful talk to a small TED University audience. Her insights from past pandemics are suddenly more relevant than ever." February 2007.

Penelope Boston says there might be life on Mars. "So the Mars Rovers didn't scoop up any alien lifeforms. Scientist Penelope Boston thinks there's a good chance -- a 25 to 50 percent chance, in fact -- that life might exist on Mars, deep inside the planet's caves. She details how we should look and why." February 2006.

Larry Brilliant wants to stop pandemics. "Accepting the 2006 TED Prize, Dr. Larry Brilliant talks about how smallpox was eradicated from the planet, and calls for a new global system that can identify and contain pandemics before they spread". February 2006.

Joe DeRisi solves medical mysteries. "Biochemist Joe DeRisi talks about amazing new ways to diagnose viruses (and treat the illnesses they cause) using DNA. His work may help us understand malaria, SARS, avian flu -- and the 60 percent of everyday viral infections that go undiagnosed." February 2006.

David Gallo on life in the deep oceans. "With vibrant video clips captured by submarines, David Gallo takes us to some of Earth's darkest, most violent, toxic and beautiful habitats, the valleys and volcanic ridges of the oceans' depths, where life is bizarre, resilient and shockingly abundant." February 1998.

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Uncovering beauty in proteins to fight the pneumococcal fratricides

This post is about pneumonia and pneumococci, fratricide at the cellular level, and a pretty protein. And there's a video too!


First things first. Pneumonia is a common disease characterized by inflammation of the lungs that can be deadly: 4 million people in the world die from it every year. Half of them are children under 5 years of age -- in fact, no other illness causes more deaths of children under age 5 worldwide. However, this is a preventable and treatable disease in most cases.


Many organisms can cause pneumonia, but the usual culprits are the bacteria Streptococcus pneumoniae (or pneumococcus, see above image) and, less frequently, Haemophilus influenzae type b (a.k.a. Hib). Safe and effective vaccines and antibiotics have been developed for these infections. Unfortunately, they are not commonly available in most developing countries, where pneumonia allies with poor nutrition, other illnesses (e.g. AIDS) and lack of resources to contribute to the cycle of poverty. To know more about the impact of pneumonia on world health and what can be done about it, I recommend listening to this podcast and visiting the World Pneumonia Day website.


My only direct contact with pneumococcus research was... hum... many years ago. As an undergraduate student, I spent two months at the Centro de Investigaciones Biológicas (CIB, Center for Biological Research) in Madrid, Spain, where I learnt how to cultivate pneumococci and some techniques for the study of lytic enzymes. These remarkable enzymes play a key role in bacterial physiology by cleaving, in a regulated fashion, specific linkages in peptidoglycan (that is, the highly cross-linked polymer that forms the bacterial cell wall). This apparently destructive activity is essential for cell wall turnover, and allows cell growth and division. Interestingly, the genomes of some bacteriophages (or bacterial viruses) also encode lytic enzymes, which the viruses use to break the cell wall and escape from its dying host after viral replication. These enzymes could be useful as antibacterial agents.


A few days ago I was happy to learn that a group of Spanish researchers --some of them from the CIB-- had solved the 3D structure of one of the pneumococcal lytic enzymes, called LytC. What I find remarkable is how the 3D structure elegantly explains the peculiar role that this protein plays during a process known as pneumococcal fratricide.

Some bacteria produce substances that kill surrounding microbes, and use the resulting dead bodies as a source of nutrients. Sometimes, killer and victim belong to the same species, or even they are siblings. In these cases, researchers speak of cannibalism or fratricide; although if you view microbial populations as coordinated, multicellular entities, then you may prefer to use the term programmed cell death.

Among pneumococci, some cells in a population become competent in response to certain signals; which means that they are able to take up DNA from their surroundings, and incorporate this genetic information into their own chromosome. This way, competent cells can acquire new inheritable abilities -- such as production of a new capsule type, or resistance to an antibiotic -- that can be very important for their survival (this was the underlying mechanism in the famous Avery-MacLeod-McCarty experiment that helped identify DNA as the hereditary material in cells).

But competent pneumococci do something else: they encourage non-competent siblings and other closely-related bacteria to commit suicide. They do this by releasing a particular lytic enzyme, called CbpD, that diffuses through the milieu and --somehow-- activates LytC and other lytic enzymes that are already present in the non-competent siblings. Cell wall weakening finally results in a big bang; that is, the explosion of the non-competent pneumococci. The materials released serve not only as nutrients and sources of genetic information (DNA), but also as virulence factors that help competent cells to survive in their human host.


The 3D structure of LytC now provides the clues to explain the enzyme's peculiar behaviour during pneumococcal fratricide. Have a look at the model of LytC on the left: ain't it a beauty? A substrate-binding module (in blue and green in the image) recognizes and binds the cell wall peptidoglycan, whereas a catalytic module (in red) is responsible for breaking a specific linkage in the substrate. Because of the unusual hook shape of the protein, the substrate-binding module and the catalytic module partially block each other. As a result, LytC cannot bind the highly cross-linked peptidoglycan that is predominant under normal circumstances. Only when CbpD or other lytic enzymes cut specific linkages in the cell wall, LytC is able to bind the 'loosened' peptidoglycan and comes into action -- with deleterious consequences for the non-competent pneumococci.


To make the story even more attractive (at least to me), the researchers bothered to produce a video that illustrates -- in a fascinating way -- the pneumococcal fratricide and the mechanism for LytC activation. Please watch it, the background music is nice too. The video includes some captions in Spanish, but I uploaded the video to YouTube and added English subtitles for a wider audience. I hope more researchers will get into the trouble of making visually attractive videos or presentations of their work (and make them freely available), it really makes a difference...




I also add here a nice composite image from the press release, just because I think it's so beautiful:




Reference for the 3D structure of LytC:
Pérez-Dorado, I., González, A., Morales, M., Sanles, R., Striker, W., Vollmer, W., Mobashery, S., García, J., Martínez-Ripoll, M., García, P., & Hermoso, J. (2010). Insights into pneumococcal fratricide from the crystal structures of the modular killing factor LytC Nature Structural & Molecular Biology DOI: 10.1038/nsmb.1817


Recommended links:
- World Pneumonia Day (November 12th).
- Keith Klugman - Pneumonia: the hidden giant. In this podcast, Carl Zimmer interviews Keith Klugman, Chair of Global Health at Emory University, USA.
- Klugman's crusade by Valerie Gregg. Public Health Magazine, Emory University, spring 2006.
- Neumococos fratricidas [in Spanish], noticia publicada en la web del CSIC (20 de abril, 2010).
- Los neumococos fratricidas [in Spanish]. RTVE.es (20-04-2010).


Other relevant scientific articles:
- Bacterial programmed cell death and multicellular behavior in bacteria [free article] by Hanna Engelberg-Kulka et al. PLoS Genet. (2006) 2(10): e135.
- Cannibalism and fratricide: mechanisms and raisons d'être by Jean-Pierre Claverys & Leiv S. Håvarstein. Nat. Rev. Microbiol. (2007) 5: 219-29.
- Bacteriophage lysins as effective antibacterials [free article] by Vincent A. Fischetti. Curr. Opin. Microbiol. (2008) 11: 393–400.
- Pneumococcus: the sugar-coated bacteria [free PDF] by Rubens López. Intl. Microbiol. (2006) 9: 179-190.


Image sources:
- Streptococcus pneumoniae in spinal fluid. FA stain (digitally colorized). Content Providers(s): CDC/Dr. M.S. Mitchell. Source: Wikimedia Commons.
- World Pneumonia Day logo.
- Nature Structural & Molecular Biology cover, May 2010, Volume 17 No 5.
- LytC model, LytC and pneumococci: both images from press release, CSIC.es

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"Hope he's only a Sunday creationist" by G. Trudeau

This comic strip by Garry Trudeau was published in 2006, so you may already know it. Here, a doctor offers two antibiotic choices to a patient suffering from tuberculosis (TB). The choice appears to depend on the patient's religious beliefs. I hope the patient chose wisely -- for his own benefit and for that of all the people that could be otherwise infected by his spreading of TB microbes.



Interestingly, cartoonist Garry Trudeau is the great-grandson of Dr. Edward Trudeau, who founded the Adirondack Cottage Sanitarium for the treatment of pulmonary TB, at Saranac Lake, New York State, in 1884. It was found at the time that tuberculous patients greatly benefited from a "rest cure" that included lots of mountain fresh air, and good nutrition. The sanatorium was later renamed and reorganized as a biomedical research center. Known today as the Trudeau Institute, it is devoted to researching our immune system to find better ways of preventing and treating human diseases, including TB, influenza, tropical diseases and cancer.



Credits for images:
- Cartoon:
Author: Garry Trudeau (Doonesbury.com). Source: GoComics.
- Stamp:
United States Postal Service. Stamp designed by Howard E. Paine and created by Mark Summers, based on a photograph of Dr. Trudeau provided by the American Lung Association. Source: The Stamp Collecting Round-up. See also a press release at EurekAlert.


Hat tip:
Comunicar ciencia con humor [in Spanish] by José Pardina, Asociación Española de Comunicación Científica (AECC) [Spanish Association for Science Communication].

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Tuberculosis and AIDS: two diseases, one response

Today is World TB Day, an excellent time to watch the following video (available at the World Health Organization YouTube channel):



You can read about the current state of the disease -- which kills almost two million people every year -- here: A world free of TB (Word Health Organization).

You can also watch a few more videos on the topic at Stop TB Partnership. I especially recommend two videos:
- Actions For Life - A flash film about the Global Plan to Stop TB
- The Human Face of TB, an informational flash film

I'll finish the post with some words written by Margaret Chan, WHO Director-General:

"If the right action is not taken right now, the continuing spread of MDR-TB [multidrug-resistant tuberculosis] could transform a disease that is curable with affordable medicines into a costly and deadly epidemic. If the right action is not taken right now, the continuing rise of XDR-TB [extensively drug-resistant tuberculosis] could take the world back to the era that predates the development of antibiotics, with nothing in hand to guarantee treatment success."

"The microbial world has given us a clear either-or situation. Either we tackle the problem now with rational and proven approaches, or we pay later with an epidemic of an airborne disease that renders our modern-day medicines and straightforward treatment regimens obsolete. This would truly be a tragedy, on a huge and costly scale, that should not happen."

Related links:
- World TB Day. Twisted Bacteria, March 24th, 2008.
- An 'open source' approach to drug discovery. Twisted Bacteria, July 1st, 2008.
- Robert Koch y la tuberculosis. En Días Como Hoy, RTVE.es , 24 de marzo, 2010. [In Spanish] Se trata de un fragmento de un programa de radio (dos minutos y medio) en el que Nieves Concostrina nos recuerda, de forma amena, el momento en que el gran Robert Koch presentó al mundo la bacteria causante de esta enfermedad ("su bacilo").

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Edward Jenner and Joseph Lister, posted

A few days ago, the UK postal service issued a new series of stamps featuring 10 eminent scientists to celebrate the 350th anniversary of the Royal Society. The image above shows two of the stamps, depicting Edward Jennner (1749-1823) and Joseph Lister (1827-1912) -- who are considered the 'fathers' of vaccination and antiseptic surgery, respectively. They both had a rough time trying to convince their fellow physicians to accept their proposed methods as good and useful practices. But they eventually succeeded, and millions of lives were saved.

It is noteworthy that Jenner was elected a fellow of the Royal Society in 1789 thanks to his research on cuckoos (the birds, not the clocks). He was a 'natural scientist' and studied a variety of issues ranging from fossils to animal behaviour, and from balloons to medicine. It was in 1796 when he carried out his famous experiments, showing that people could be protected against the deadly smallpox by inoculating them with cowpox (a mild, related disease). Although the basic rationale behind Jenner's technique was not novel (but this was not the reason why the Royal Society rejected his original report!), his careful studies and his tenacity were fundamental for a wide progressive adoption of vaccination. Now --two centuries later-- the world can celebrate the 30th anniversary of smallpox eradication. This deserves a stamp or two, doesn't it?

Now, let's turn our look to Joseph Lister. He introduced phenol (carbolic acid) to sterilise surgical instruments and to clean wounds. As a result, post-operative infections were greatly reduced, and many lives (and body parts that otherwise would be amputated) were saved. Because of these achievements, Lister was not only elected fellow but president of the Royal Society (between 1895 and 1900), and his name was given to a bacterium ...and a mouthwash (what an honour!).

Anyway, it seems that there was some kind of infectious hunger for 'small knowledge' at the Listers' house, as Joseph was not the only one interested in the microscopic world. His father, Joseph Jackson Lister (1786-1869), made crucial advances toward correcting image aberrations in microscopes (and he was elected fellow of the Royal Society in 1832). After his work, the improved microscopes became powerful instruments, allowing more detailed observations of specimens and, hence, the birth of modern histology.

Now this may not come as a surprise to you, but (at least) two other members of the family were also elected fellows of the Royal Society. They were Arthur Lister (1830-1908, Joseph's brother) and Gulielma Lister (1860-1949, Arthur's daughter). Arthur and Gulielma became renowned botanists and mycologists, and world experts in mycetozoa (myxomycetes, slime molds). I'm wondering if they started by playing with J.J.'s old microscope? Gulielma's achievements are especially remarkable in a time (early 1900's) when very very few women were allowed to excel in science: she was a founding member of the British Mycological Society (and president in two occasions), as well as fellow, council member and vice-president of the Linnaean Society. Does anybody know of a stamp featuring Gulielma? Probably not (yet) but this could be a good topic for the next International Women's Day...


Further reading:

Stamps commemorating the Royal Society anniversary:
- Getting the Royal Society stamp of approval by Charlotte King. New Scientist, 25 Feb 2010. It includes large-size images of the 10 stamps.
- The Royal Society 350 Years, British Postal Museum & Archive.
- Science stamps mark the Royal Society's 350th anniversary, Royal Society, 24 Feb 2010.
- 350th Anniversary of the Royal Society, new Great Britain stamps, Norvic Philatelics. Includes interesting technical details and image credits, and a few special postmarks.

Edward Jenner and smallpox:
- Edward Jenner Museum, Gloucestershire, UK. Excellent website with plenty of information.
- Edward Jenner and the history of smallpox and vaccination by Stefan Riedel, Proc (Bayl Univ Med Cent) (2005) 18, 21–25.
- Edward Jenner (1749-1823), historical figures, BBC.
- Smallpox, World Health Organization.

Joseph Lister and his relatives:
- Joseph Lister: Surgery Transformed, a video produced by British Medical Journal Media.
- Joseph Jackson Lister (1786-1869), Pioneers in Optics. Science Optics & You, Molecular Expressions.
- Early Myxomycetologists (including Arthur and Gulielma Lister), Myxoweb.
- Gulielma Lister (1860-1949), biography, Wanstead Wildlife.
- Biography of Gulielma Lister (1860-1949), The Biographical Dictionary of Women in Science: L-Z. By Marilyn Bailey Ogilvie, Joy Dorothy Harvey.

Microbiology (and other sciences) featured on stamps:
- Microscopy on stamps by Dave Walker, Microscopy-UK. Great article, together with the following one:
- Photomicrography on stamps by Dave Walker, Microscopy-UK.
- Physics-related stamps, compiled by Joachim Reinhardt. Mostly about physicists, but there are also a few other scientists, mathematicians and engineers (including Antonie van Leeuwenhoek and Robert Hooke).
- Science and Technology on Stamps, A to Zee ("the web guide for collectors").
- Sci-Philately: a Selective History of Science on Stamps by Maiken Naylor, University at Buffalo Libraries.
- Medical Stamps, Scientific-web.com
- Filatelia Médica - Medical Stamps by Dr Tuoto.
- Pasteur on Stamps by Dr Tuoto.
- AIDS on Stamps.
- Malaria on Stamps Collection.
- Collect GB Stamps, resources for collecting British stamps. It has a good search tool.

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The Seven Dwarfs' battle against malaria

In this short Disney film (The Winged Scourge, 1943), the Seven Dwarfs teach us how to protect ourselves from the mosquitoes that transmit malaria. But some of their methods may not be quite advisable today...




Thanks to MicrobeWorld for letting me know about this video!

A collection of old Disney documentaries (including this one) can be viewed at thelostdisney channel on YouTube.

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Paul Ewald: Can we domesticate germs?

TED (Technology, Entertainment, Design) is a group of conferences that "brings together the world's most fascinating thinkers and doers, who are challenged to give the talk of their lives (in 18 minutes)." The following video corresponds to a talk by Paul Ewald, director of the program in Evolutionary Medicine at the Biology Department of the University of Louisville; he has written popular news articles, academic papers, and two books. In his conference, Ewald reasons that, for the control of infectious diseases, alternative strategies should be privileged over the never-ending development of more new drugs. The central idea consists of creating conditions that favor the less virulent variants of pathogenic microbes — in contrast to the present rise in drug-resistant strains due to the overuse of anti-infective medicines.



Link for the video at TED (filmed on March 2007): Paul Ewald: Can we domesticate germs?.
Or view it at YouTube.

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Neglected diseases in the news

The so-called neglected diseases comprise a number of parasitic and bacterial infections which are the most common afflictions of humankind. So, how can these diseases be "neglected"? When you get sick, you don't ignore your illness, do you? But we all can ignore a disease... as long as we ourselves don't suffer it.

Neglected diseases are especially endemic in low-income populations in developing regions of Africa, Asia, and the Americas. They mostly affect the poorest people, living in remote rural areas, urban slums or conflict zones. In the meantime, the rest of humankind just "neglect" those pains, as exemplified by the poor coverage on news media.

(If you already know about these diseases, just jump to the paragraph starting with "An interesting study...")

According to the Global Network For Neglected Tropical Disease Control, the most prevalent neglected tropical diseases are:

Disease	Causative agents	Affected people
Soil-transmitted helminthiases	Several nematodes: roundworm (Ascaris lumbricoides), whipworm (Trichuris trichiura), hookworms (Ancylostoma duodenale, Necator americanus)	Over 2 billion infected; over 70,000 deaths/year
Lymphatic filariasis (elephantiasis)	Several nematodes: Wuchereria bancrofti, Brugia malayi, B. timori	Over 120 million infected; 40 million with clinical symptoms
River blindness (onchocerciasis)	A nematode (Onchocerca volvulus)	37 million infected; 500,000 visually impaired; 270,000 blind
Schistosomiasis (bilharzia)	Several flukes (trematodes) of the Schistosoma genus	200 million infected; over 200,000 deaths/year
Trachoma	A bacterium (Chlamydia trachomatis)	84 million infected; 8 million visually impaired or irreversibly blind

But, unfortunately, the list of neglected diseases is much longer, including:
[disease name, causative agent]

• Sleeping sickness (African trypanosomiasis), Trypanosoma brucei (protist).
• Chagas' disease (American trypanosomiasis), Trypanosoma cruzi (protist).
  
• Leishmaniasis, Leishmania spp. (protist).
• Cholera, Vibrio cholerae (bacterium).
• Buruli ulcer, Mycobacterium ulcerans (bacterium, actinomycete).
• Leprosy, Mycobacterium leprae (bacterium, actinomycete).
• Yaws, Treponema pertenue (bacterium).
• Dengue/dengue haemorrhagic fever, Dengue virus.
  
• Dracunculiasis (guinea-worm disease), Dracunculus medinensis (nematode).
  
• Fascioliasis, Fasciola hepatica and F. gigantica (trematodes).
• A number of other neglected zoonoses (anthrax, rabies, etc.).
  

Wow, if you are still reading this, you must be really interested. Or you've just jumped over all those boring, unpronounceable words. That's OK. But the title of the post said "in the news", so let's go.


An interesting study has just been published on the open-access journal PLoS Neglected Tropical Diseases, showing that these diseases rarely make the headlines... Oh, wait, we already knew that. True —but this report seems to be the first one trying to analyze, in a quantitative manner, the international media coverage of neglected diseases, as a support for future advocacy work.

The authors searched the archives of 11 English-language media, from January 2003 to June 2007, including 6 newspapers (The New York Times, Los Angeles Times, Washington Post, The Guardian, The Daily Telegraph, The Financial Times), BBC Online, CNN.com, Agence France Presse (AFP), and two news magazines (Time and The Economist). They analyzed coverage of "neglected diseases" in general, with a focus on African trypanosomiasis, leishmaniasis and Chagas' disease (probably not the most neglected). The researchers also interviewed leading health journalists, highlighting factors influencing reporting.

During the study period, they found only 113 articles on neglected diseases. In comparison, there were over 1000 articles on HIV/AIDS in the AFP database alone during the same period. There was wide disparity in coverage between the various media: the BBC had the highest coverage (20 articles), while CNN had the least coverage (only 1 article). Coverage of global health issues was particularly poor in the American media.

As the authors recognize, it would be useful to expand the analysis, including more international media and languages other than English. However, the selected media may be considered a useful sample, and some patterns emerged:

" For example, the penchant for a local angle was even parochial at times. Stories get written about leishmaniasis in pets before humans, as was seen in The Daily Telegraph. "

In the interviews, journalists explained that the main obstacles for reporting on these issues were: a lack of real news development, the drive to cater to domestic audiences, and competing health interests.

" “Poor people dying from an illness is not news,” unless there is some change or development, one producer from an international broadcaster said. But HIV/AIDS was widely reported on “because it sells stories” and has the funding and attention of policymakers. "

That's perfectly understandable: news media need to make a living, and only "newsworthy" stories get the attention. Here, the role of health agencies (either public or private) is essential: all journalists said health agencies were not communicating adequately about the burden of neglected tropical diseases. Some organizations (World Health Organization, Bill & Melinda Gates Foundation) were criticized for the difficulty in reaching officials for comment, while non-governmental organizations such as Médecins Sans Frontières (MSF) were cited as good sources for stories.

News coverage was also difficult due to the lack of powerful "human" stories from the field (including interviews with patients).

" The “human element” was powerful, but few journalists were able to get such stories first-hand from the field. This represented a real constraint for coverage. One communications advisor (consulting for DNDi) said health agencies needed to present stories featuring “real people” rather than “experts in their ivory towers” and the “yuck” factor about these diseases needed to be played up to “grab the public imagination” rather than facts about the lifecycle of the parasite. "

Remarkably, journalists who did cover these diseases were often personally motivated. Andrew Jack (Financial Times), who authored the largest number of articles detected in the study, said his reporting was “100%” driven by his interest.

In other words, a single individual can make a difference.


Original article (open access):
Balasegaram, M., Balasegaram, S., Malvy, D., Millet, P., Hotez, P.J. (2008). Neglected Diseases in the News: A Content Analysis of Recent International Media Coverage Focussing on Leishmaniasis and Trypanosomiasis. PLoS Neglected Tropical Diseases, 2(5), e234. DOI: 10.1371/journal.pntd.0000234



Related links:

• Neglected Diseases, Wikipedia.
• About Neglected Tropical Diseases (NTDs), at Global Network For Neglected Tropical Disease Control. Actress Alyssa Milano is Global Network's lead ambassador.
• Why are some tropical diseases called "neglected"? World Health Organization.
• Diseases covered by NTD Department, World Health Organization.
• PLoS Neglected Tropical Diseases, Public Library of Science.
  

Image credits:
Trypanosoma forms in blood smear from patient with African trypanosomiasis. Source: Public Health Image Library (PHIL). Content provider: CDC/Dr. Myron G. Schultz.

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World TB Day

From WHO - A world free of TB (WHO = World Health Organization, TB = tuberculosis):

"Tuberculosis is an airborne infectious disease that is preventable and curable. People ill with TB bacteria in their lungs can infect others when they cough. An estimated 1.5 million people died from TB in 2006. In addition, another 200,000 people with HIV died from HIV-associated TB. If TB disease is detected early and fully treated, people with the disease quickly become non-infectious and eventually cured. Multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB), HIV-associated TB, and weak health systems are major challenges."

"WHO is working to dramatically reduce the burden of TB, and halve TB deaths and prevalence by 2015, through its Stop TB Strategy and supporting the Global Plan to Stop TB."

"Worldwide efforts to confront tuberculosis are making progress, but too slowly"

From Stop TB Partnership - World TB Index:

"World TB Day - March 24th
World TB Day, falling on 24 March each year, is designed to build public awareness that tuberculosis today remains an epidemic in much of the world, causing the deaths of several million people each year, mostly in the third world. 24 March commemorates the day in 1882 when Dr Robert Koch astounded the scientific community by announcing that he had discovered the cause of tuberculosis, the TB bacillus. At the time of Koch's announcement in Berlin, TB was raging through Europe and the Americas, causing the death of one out of every seven people. Koch's discovery opened the way toward diagnosing and curing tuberculosis."

At Stop TB Partnership - Video Library you can watch some educational videos on TB.

Just in case you don't know, the scientific name for the "TB bacillus" is Mycobacterium tuberculosis. The TB bacillus is an actinomycete.

Photo credit: Janice Carr.
Source: Public Health Image Library. Content providers: CDC/ Dr. Ray Butler; Janice Carr.

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