malaria

Student guest post by Laura Vonnahme As a part of traveling to a developing nation, we are often required to take medical precautions. This generally includes a line-up of shots for various diseases, a few other tests, and various regimens of prophylaxis for possible diseases. I have often left these doctors appointments with a line of band-aids on my arm, a handful of prescriptions and a little weakness in my knees. However, I will readily admit that my malaria prophylaxis is often pushed to the back burner; in fact the last time I went to a developing nation, I didn't even get the malaria…

We've all heard about "beer goggles", the mythical, invisible eyewear that makes everyone else seem incredibly attractive after a few pints too many. If only beer had the reverse effect, making the drinker seem irresistibly attractive. Well, the good news is that beer does actually do this. The bad news is that the ones who are attracted are malarial mosquitoes. Anopheles gambiae (the mosquito that transmits malaria) tracks its victims by their smells. By wafting the aromas of humans over thousands of mosquitoes, Thierry Lefevre found that they find the body odour of beer drinkers to be…

Paul "Magic Water" Sheehan offers a "counter perspective" to Monckton's big lie that environmentalists killed 40 million people by banning DDT: The claim that millions have lost their lives as a result of the withdrawal of DDT is hotly contested among scientists. Speculation over the number of deaths caused by the withdrawal of DDT ranges from thousands to tens of millions. Yes, his counter perspective is just a smaller lie. Anyone interested in the truth can easily discover that the anti-malarial use of DDT has never been banned, and that by slowing the evolution of resistance, the ban on…

The Tyee has published an extract from a book by Donald Gutstein on corporate propaganda in Canada: In the years since the Stockholm Treaty was signed, readers of Canadian newspapers have not had an opportunity for Greenpeace's position on DDT to be explained to them by Greenpeace itself. The only information they received about this environmental organization's position on DDT was conveyed by the organization's foes. National Post readers learned, for instance, courtesy of then columnist Elizabeth Nickson, that "groups like Greenpeace... serve their own ideological agenda, and want to keep…

This is an updated version of the first post I wrote this year. The scientists in question were looking at ways of recruiting bacteria in the fight against mosquito-borne diseases, such as dengue fever. They've just published new results that expand on their earlier experiments. Mosquitoes are incredibly successful parasites and cause millions of human deaths every year through the infections they spread. But they are no match for the most successful parasite of all - a bacterium called Wolbachia. It infects around 60% of the world's insect species and it could be our newest recruit in the…

Around 2600 years ago in Egypt, a woman called Irtyersenu died. She was mummified and buried at the necropolis at Thebes, where she remained for over two millennia before being unearthed in 1819. Her well-preserved body was brought to the British Museum where it was examined by the physician and obstetrician Augustus Bozzi Granville. It was the first ever medical autopsy of an Egyptian mummy and Granville presented his results to the Royal Society in 1825. His conclusion: Ityersenu died of ovarian cancer. The mummification techniques of ancient Egypt were so good that Irtyersenu's corpse…

This week, Public Radio International is hosting a forum whereby you- the fine people of the General Public- get a chance to converse online with eminent entomologist May Berenbaum about all things DDT. The forum accompanies a piece from last week's "The World".  For background, you can read Berenbaum's recent Washington Post essay about the DDT-malaria problem here: What people aren't remembering about the history of DDT is that, in many places, it failed to eradicate malaria not because of environmentalist restrictions on its use but because it simply stopped working. Insects have a…

Swine flu has made the world all too aware of the possibility of diseases making the leap from animal hosts to human ones. Now, we know that another disease made a similar transition from chimpanzees to humans, several thousand years ago. This particular infection is caused by a parasite, and a very familiar and dangerous one - Plasmodium falciparum, the agent responsible for malaria.  Transmitted by the bite of mosquitoes, P.falciparum infects over 500 million people every year. Its closest relative is a related parasite, Plasmodium reichenowi, which infects chimpanzees. Leading an…

Seed Magazine has interviewed epidemiologist Barbara Eskanazi about her survey article on the effects of DDT on human health: SEED: What kinds of long-term health problems can we expect? BE: I don't really know. I can't predict, but I can say that if the studies that I read hold true we may see higher rates of diabetes; we may see higher rates of breast cancer; we may see higher rates of male infertility. We may see poor neurodevelopment in children. We may also see more spontaneous abortions. ... SEED: How do we balance the malaria-fighting benefits of DDT with this information about long…

The United Nations Environment Programme and the World Health Organization have announced new projects to test methods for fighting malaria with less use of DDT: Ten projects, all part of the global programme "Demonstrating and Scaling-up of sustainable Alternatives to DDT in Vector Management", involving some 40 countries in Africa, the Eastern Mediterranean and Central Asia are set to test non-chemical methods ranging from eliminating potential mosquito breeding sites and securing homes with mesh screens to deploying mosquito-repellent trees and fish that eat mosquito larvae. The new…

A recent peer-reviewed scientific paper in Malaria Journal by Yukich, Lengeler, Tediosi, Brown, Mulligan, Chavasse, Stevens, Justino, Conteh, Maharaj, Erskine, Mueller, Wiseman, Ghebremeskel, Zerom, Goodman, McGuire, Urrutia, Sakho, Hanson and Sharp compared several large vector control programs to prevent malaria, including both insecticide-treated nets (ITN) and indoor residual spraying (IRS). The results: Method cost per child death averted Conventional ITNs $438-$2199 Long-lasting ITNs $502-$692 IRS $3933-$4357 Even using IRS, DDT was not the most cost effective insecticide,…

Okay people, these students in Miss Stacy Baker's biology classes and Extreme Biology blog have been rocking my world for quite some time. They've now burst onto the national media and were all the buzz of the recent ScienceOnline'09 conference. For those not familiar with the story, Stacy Baker is a biology teacher at the Calverton School in Huntingtown, Maryland, who began a website for student activities and class notes back in 2006. With the boundless enthusiasm of ninth-graders and more seasoned AP biology students, the site has become interactive: a blog, Extreme Biology, with videos…

Fighting malaria with mosquitoes seems like an bizarrely ironic strategy but it's exactly what many scientists are trying to do. Malaria kills one to three million people every year, most of whom are children. Many strategies for controlling it naturally focus on ways of killing the mosquitoes that spread it, stopping them from biting humans, or getting rid of their breeding grounds. But the mosquitoes themselves are not the real problem. They are merely carriers for the true cause of malaria - a parasite called Plasmodium. It suits neither mosquitoes nor humans to be infected with…

Well, you certainly can't fault Obama for aiming high. Via satellite, Obama announced at yesterday's Clinton Global Initiative forum that he would provide support to end malaria deaths in Africa by 2015--a lofty goal, but is it even close to attainable? Obama provided the basics of his plan here, laying out why he feels this is such an important goal: Malaria needlessly kills 900,000 people each year. In Africa, a child dies from a mosquito bite every thirty seconds. Beyond this devastating human toll, malaria undermines the economic potential of local economies and overwhelms public…

Last year, I blogged about an ironic public health strategy - controlling malaria with mosquitoes. The mozzies in question are genetically engineered to be resistant to the malaria parasite, Plasmodium. The idea is that these GM-mosquitoes would mate with wild ones and spread their resistance genes through the natural population. The approach seems promising but it relies crucially on the ability of the resistant males to successfully compete for the attentions of females in wild populations. The 1960s and 1970s witnessed several failed attempts to control malaria by swamping natural…

Over at Evolgen, RPM notes an interesting study in PNAS, looking at antibiotic use and how it serves to drive the emergence and maintenance of antibiotic-resistant strains. The current paradigm for antibiotic use is to prescribe relatively high doses of drugs for a few days to a few weeks (or months, in the case of tuberculosis), and patients are cautioned to stay on them until all the doses are finished. However, the new study RPM describes suggests this may be doing more harm than good, looking at what happens with Plasmodium species treated with antimalarials in a mouse model. Do…

I asked yesterday what readers considered the most important diseases in history. This was prompted by a new ASM Press book, Twelve Diseases that Changed Our World, written by Irwin Sherman. As I mentioned, Sherman included many diseases readers expected--plague, cholera, tuberculosis, smallpox, syphilis, malaria, influenza, yellow fever, and AIDS. He didn't include a few that popped up repeatedly in the comments--leprosy, measles, and typhoid (or typhus, for that matter). While I think a study of these could have been illuminating (especially leprosy, since much of the stigma…

A few other topics readers here may appreciate: First and foremost, this week's Grand Rounds can be found over at Over my med body!. Next week, however, it will be hosted right here at Aetiology for the second time, so send your posts along to me (aetiology AT gmail DOT com), preferably by Sunday evening. Pediatric Grand Rounds also had a new edition over the weekend, which can be found over at Shinga's Breath Spa for Kids. National Geographic's July cover story is on malaria--a really good read. (via Panda's Thumb). Matt Nisbet was late to the scientists and journalists conversation. He…

Over at The Examining Room of Dr. Charles, the good doc brings up another instance of quackery from an unexpected source: Dr. Henry Heimlich, originator of the Heimlich maneuver for choking. While that procedure has clearly saved many lives, Dr. Heimlich doesn't stop there--he advocates using his maneuver for drowning victims and asthmatics, neither of which have been scientifically proven (and indeed, major medical associations have spoken out against them). Dr. Charles also reveals that Heimlich also carries out other questionable research, including deliberately infecting HIV+…

You've probably already seen a few reviews of Michael Behe 's new book, The Edge of Evolution. I've barely cracked open my review copy yet, but I already know that one example that features prominently throughout the book is malaria (hence my interest in it, moreso than any more "irreducible complexity" or bad math). However, Nick's already managed to take away some of my interest even in the malaria angle, dang him. More below... One of Behe's arguments, much like in Darwin's Black Box, centers on "irreducible complexity" in the construction of cellular flagella (and adds eukaryotic…