Nodding syndrome, a disease that has sickened more than a thousand children in northern Uganda since the summer, is named for its most distinctive symptom: involuntary, at times violent bobbing of the head, like someone repeatedly nodding yes or snapping out of a doze. Outbreaks of nodding syndrome cropped up in South Sudan this summer, in the same region of Uganda two years ago, in southern Sudan—not yet an independent nation—in 2001, and periodically in remote mountain villages in Tanzania. Nearly half a century has passed since the first reported case, but epidemiologists still have only a rudimentary understanding of this mysterious disease. They’ve found few hints as to what might cause it, and no effective treatments.
Posts Tagged ‘Africa’
Scientists Find the Oldest Known Sleeping Mats, Laced With Insect-Repelling Leaves

Remnants of a Cryptocarya woodii leaf, which researchers
say was part of the oldest bedding ever found
In a South African cave, researchers have uncovered traces of the oldest known human bedding, 77,000-year-old mats made of grasses, leaves, and other plant material. While it’s not especially surprising that early humans would have found a way to improve the cold, generally unpleasant experience of sleeping on a cave floor, archaeologists know little about our ancestors’ sleeping habits and habitats.
Satellite Photos Show Ancient Saharan Fortresses of a Lost Empire

New satellite images have revealed more than a hundred ancient fortified settlements still standing in the Sahara. The settlements, located in what today is southern Libya, were built by the Garamantes, a people who ruled much of the area for nearly a thousand years until their empire fragmented around 700 AD. Information about the Garamantes is relatively scarce: Other than the accounts of classical historians (who aren’t known for careful accuracy) and excavations of the Garamantian capital city in the 1960s, archaeologists haven’t had a lot to go on. During the decades-long reign of Muammar Gadhafi, antiquities and archaeology weren’t exactly a national priority; the fortresses were largely ignored. As David Mattingly, the British archaeologist who led the project, said to OurAmazingPlanet of the discoveries: ”It is like someone coming to England and suddenly discovering all the medieval castles.”
Malaria Vaccine Cuts Risk of Infection By Half
Blood smear of the Plasmodium falciparum parasite
Preliminary results from the largest ever field trial of a malaria vaccine show the vaccine cut infant’s risk of getting the disease by half. In development for more than 25 years by GlaxoSmithKline and others, the vaccine cut the risk of catching severe malaria by 47 percent amongst infants ages 5 months to 17 months in the year after receiving it. 6,000 kids enrolled in the study, whose early results were published yesterday in the The New England Journal of Medicine and announced at a Seattle conference organized by the Bill and Melinda Gates Foundation, a major funder of the study and other efforts to combat malaria. The vaccine represents the first against a parasite-borne infection and has been notoriously difficult to develop since the protozoan that causes the illness (mainly Plasmodium falciparum) changes shape as it moves from the blood to the liver and back again.
While 47 percent isn’t very effective—most vaccines aren’t approved until they reach 90 percent or better—even this level of protection could save millions of lives, Glaxo’s chief executive Andrew Witty tells the New York Times. Malaria kills an estimated 780,000 per year, despite being preventable and treatable, mostly claiming the lives of African children.
[Via The Guardian]
Image: CDC / Wikimedia
Birth Control Shots May Double the Risk of HIV, Study Suggests

For African women looking to avoid pregnancy, hormone shots seem like a good choice. They don’t require your partner to take responsibility for birth control, and they can be given once and then forgotten about for months. But that could be shaken by a study of nearly 4,000 women in seven African countries that found that hormone shots double a woman’s risk of contracting HIV, as well as doubling the risk of her passing it on to a partner. And it doesn’t appear to be because of decreased use of condoms in couples where the woman is on the shot: the researchers, who published their work in The Lancet Infectious Diseases, accounted for that, and found that the effects were still there.
Why this happens isn’t clear, but it’s possible that the hormones in the shot may alter the environment of the female reproductive tract to make it a more livable place for HIV. The team found that those on the shot have higher concentrations of the virus in their genital fluid than those not on birth control, though blood levels remain the same, suggesting that there’s something to the idea that the vaginal environment is altered. More work probing this finding will be required, perhaps including a randomized controlled study, which this was not. But going forward, the researchers say, doctors providing birth control shots in clinics in Africa, where the prevalence of HIV is a public health crisis, should emphasize that condoms should be still be used in order to avoid spreading or contracting the virus.
[via the NYTimes]
Image courtesy of a.drian / flickr
A Daily Pill Can Prevent HIV Transmission, Two Studies Show
What’s the News: A daily dose of anti-HIV drugs can significantly reduce the likelihood that straight men and women will contract HIV from an infected partner, according to two new clinical studies. These studies add strong evidence to earlier findings that taking HIV drugs can prevent healthy people from contracting the disease, and are the first to show that the drugs reliably lower transmission risk in heterosexuals.
Guardian Bees Protect Kenyan Crops from Roaming Elephants

What’s the News: We’ve all probably heard the myth, made popular by Disney’s Dumbo, that elephants are afraid of mice. While that idea may not be exactly true (video), elephants do make sure to avoid another tiny critter: bees. Knowing this, zoologists from the University of Oxford loaded fences in Kenya with beehives, in hopes of deterring roaming African elephants from eating or trampling farmers’ crops. Now, two years later, the researchers are reporting in the African Journal of Ecology that the novel barriers are working wondrously and could be a viable option for protecting African croplands.
Rising Sea of Humanity: UN Says Pop. Will Hit 10B by 2100—& Keep Going Up
What’s the News: The world’s population is projected to reach 7 billion this October and continue climbing, reaching 10.1 billion by the end of the 21st century, says an official United Nations report (PDF) released earlier this week. This is a significant departure from earlier projections that said the population would peak at just over 9 billion, then level off and even slightly decline.
News Roundup: Where We’re From, Apple for Life, Elephants & Teamwork
- Out of Africa: Touted as a “landmark study,” new genetic research suggests that the first humans came from southern Africa. In the study, they found more genetic diversity in the southern part of the dark continent—an indicator of longevity. Experts had previously pinned eastern Africa as the starting line for the human race.
- An apple a day keeps the fruit fly alive: Researchers discovered that fruit fly lifespans increase by about 10 percent when they’re fed a daily bit of apple. And the benefits don’t stop there: The apple’s healthful antioxidants also helped the flies’ walking and climbing abilities. Scientists note that because this research agrees with past apple studies on other animals, it should encourage more apple eating by humans too.
- Want to know your risk of lung cancer? Look down. The nicotine levels in your toenail clippings give an accurate idea of future lung cancer risk, according to new research: The men with the highest nicotine levels (mostly smokers, but also some second-hand smokers) were more than three times as likely to develop lung cancer as those with the lowest levels.
Who Needs Twitter? Libyan Protesters Covertly Connect on Dating Website
“May your day be full of jasmine.” “My lady, how I want to climb this wall of silence.” “I LLLLLove you.” No, this isn’t the tortured verse of botanically inclined lovesick teens. It’s the coded poetry of revolution.
As uprisings spread across northern Africa this month, protesters lit up social networking sites with updates—even Egypt’s attempt to shut off the Internet couldn’t stop them completely. But in Libya, where the fight is getting hotter and hotter, few people use sites like Facebook or Twitter, and many would be afraid to write there openly. So protest leader Omar Shibliy Mahmoudi found a place where they could speak in code: dating sites.
Mahmoudi – leader of the Ekhtalef, or “Difference,” movement – acted as if he was looking for a wife under the profile name “Where is Miriam?” and sent coded love letters to spur people to revolution. Since men cannot talk to other men on the site, revolutionaries posed as women to make contact with Mahmoudi, taking on names such as “Sweet Butterfly,” “Opener of the Mountain,” “Girl of the Desert” and “Melody of Torture.” [Herald Sun]
Once Mahmoudi connected with his sham love interests on the website (called Mawada), they bantered in cryptic poetry to suss out the other’s feelings. The “jasmine” reference above is a nod of support to the ongoing Jasmine Revolution. The five L’s in “”I LLLLLove you” means that a person has five supporters with them.
How Sandfish Lizards Slither So Quickly Through the Sahara
Sandfish lizards jostle back and forth, bending their bodies into a slithery S-curve to swim through the sands of the Sahara. Like scorpions and several other native desert species, they long ago mastered the difficult art of moving through the myriad grains of a sandy expanse to escape predators or the blistering African sun. And now physicists are close to cracking their secrets.
Daniel Goldman’s team has been trying to figure out just how the sandfish lizards do it for years now; in 2009 they built a robot to simulate the creature’s slithering motion. This time, for a study in the Journal of the Royal Society Interface, the scientists tried to model the physics of an animal knocking around so many grains of sand and see how the lizards burrow with such efficiency.
The team found sine-wave-like movement allows the lizard, and their robot, to push forward in sand, but creating computer models for the experiments proved problematic. Simulating all of the tiny sand grains required a lot of money to purchase time on powerful computers. So, the team performed the same experiments using 3-millimeter-wide glass beads instead of sand. “We wanted something easy to simulate that had some predictive power. We got lucky, because it turned out [the lizard and robot] swim beautifully in the same way through larger glass beads,” Goldman said. [Wired]
Good News & Bad News for the World’s Troubled Forests
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The state of our forests is troubled, but maybe on the mend.
The United Nations, as part of its effort to brand 2011 the International Year of Forests, released an assessment this week about forest extent, and quality, all around the world. First, the good news: Forest destruction is slowing down, according to assistant director general Eduardo Rojas-Briales of the UN’s Food and Agriculture Organization.
The 4.032 billion hectares (9.9 billion acres) of forests in the world in 2010 is down from an estimated 4.085 billion in 2000, said the FAO. But the speed at which which trees are being cut down is slowing from 8.3 million hectares a year in 1990-2000 to 5.2 million in the past decade. “There are evident signs that we could arrive at a balance in a few years,” said Rojas-Briales, adding that the deforestation rate was 50 million hectares a year 30 years ago. [AFP]
Asian countries have achieved particularly impressive results, with many adding to their total of forested territory.
“China has increased its forest by three million hectares (30,000 sq km) per year – no country has ever done anything like this before, it’s an enormous contribution,” said … Rojas-Briales. “But we can also highlight the case of Vietnam, a small and densely populated country that’s implemented very smart and comprehensive forest reform – or India, which has not controlled its population as China has and where standards of living are even lower. Nevertheless India has achieved a modest growth of its forest area.” [BBC News]
But the world is not out of the woods, so to speak, in bringing back the forest health of old.
Did Early Humans Migrate Across a Watery, Green Sahara?
The “cradle of humanity” is thought to be located in Sub-Saharan Africa–meaning below the Sahara, the largest hot desert on earth. So how was humanity able to breach such an intimidating barrier to spread out across the rest of the world?
Until now, anthropologists typically argued that hominids could only have followed the lush Nile River valley north in order to reach the Middle East and beyond. But new research is suggesting that the Sahara might not have been an impassable barrier to those humans after all. Some animals (including several fish species) are found on both the north and south sides of the desert, and even in some safe-haven ponds in between. The researchers argue that if these ancestral fish could swim across the region that we now know as the Sahara, humans could have also made it across.
“Fish appeared to have swam across the Sahara during its last wet phase sometime between 10,000 and 6,000 years ago,” researcher Nick Drake, a geographer at King’s College London, told LiveScience. “The Sahara is not a barrier to the migrations of animals and people. Thus it is possible–likely?–that early modern humans did so, and this could explain how we got out of Africa.” [LiveScience]
Artifacts Show an Advanced Stone Age Toolmaking Repertoire
A bountiful archaeological site in South Africa has given up another discovery showing humans becoming sophisticated tool users. According to a study out in the journal Science, 75,000-year-old artifacts in the Blombos Cave appear to show signs of pressure flaking, a process of finely shaping hard material. Before this, study author Paola Villa says, the oldest evidence of humans using the technique was dated to just 20,000 years ago.
Pressure flaking consists of trimming the edges of a finished tool by pressing with a bone point hard enough to remove thin slices of rock. This process creates the narrow, evenly spaced grooves found on flint tools from Europe’s 20,000-year-old Solutrean culture and prehistoric Native American groups. Wider, more irregular grooves characterize 36 pressure-flaked Blombos tools, which were made from silcrete, Villa says. This rock, a silica-rich material, is of lower quality than flint and requires heating to ready it for pressure flaking. [Science News]
It’s not easy to tell from these artifacts whether their makers simply hammered them into shape or used the more sophisticated flaking method to polish them off. So the team, led by Vincent Mourre, found silcrete around the cave site and tried to make their own.
Into Africa: Did the Earliest Primates Migrate From Asia?
You know the “out of Africa” story: how our ancestors left the savannas where humanity grew up and trekked outward to other continents. Today in Nature, however, a new study of 40 million-year-old fossils argues that an “into Africa” story predates the other narrative: that the animals that would eventually evolve into apes like us and monkeys came from Asia into Africa.
These fossil teeth found in Libya belong to early anthropoids, according to the scientists. The team found several different species in this location.
The new fossils are about 38 to 39 million years old, and none of the animals would have weighed more than 500 grams [just more than 1 pound], conclude a team led by Jean-Jacques Jaeger, a palaeontologist at the University of Poiters, France. Their diminutive size fits in with previous research suggesting that early anthropoids started small and eventually evolved ever bigger bodies. [Nature]











