Stories tagged Africa

May
08
2008

Fighting AIDS in Africa: Many people are at risk, but officials disagree over the best approach.
Fighting AIDS in Africa: Many people are at risk, but officials disagree over the best approach.Courtesy Stig Nygaard

Two years ago, an article in the journal Science noted that rates of AIDS infection were falling in Zimbabwe, south east Africa, thanks to the “ABC” program. “ABC” stands for “Abstinence, Be faithful, use Condoms” – three things that help prevent the spread of sexually-transmitted diseases. Other countries using the ABC approach, including Uganda and Kenya, also report success in stemming the tide of AIDS.

The report was in the news again lately as Congress debates funding for the President's Emergency Plan for AIDS Relief (PEPFAR). Rep. Chris Smith of NJ cited this and other studies as evidence of the program effectiveness. (An argument for continuing the funding can be found here. )

The program is controversial, however, because it adds a moral dimension to medical treatment. Many aid workers don’t want to be in the position of telling people how to live, or imposing a particular view of right and wrong behavior on another culture. They would rather just treat the disease. OTOH, this particular disease spreads through a particular behavior. Programs that rely exclusively on condoms without any behavioral component have had little success against the AIDS epidemic.

Some people see this controversy as playing politics with a world health crisis. But others take it very seriously. In 2005, Brazil refused to accept US funds for their AIDS program because it came with the requirement that workers try to discourage prostitution. Many aid groups argue that such a provision hurts their ability to reach the people who need help the most. The government argues that discouraging prostitution and sex trafficking makes all kinds of sense when combating an STD.

It would be good to get this sorted out soon, since there is no vaccine against AIDS, and some scientists believe it may be impossible to ever make one.

What do you think? Should aid workers try to combat disease by changing people’s behavior? Or should they just stick to medicine? And should government funding come with such restrictions? Leave us a comment.

Apr
07
2008

Measles rash: This young boy has a 3 day old rash caused by the measles virus.
Measles rash: This young boy has a 3 day old rash caused by the measles virus.Courtesy CDC PHIL #1152

Recently, twelve people were diagnosed with measles in San Diego, another nine in Pima County Arizona. In Salzburg, Austria 180 people have been infected during a recent outbreak. Thankfully there haven’t been any deaths from these latest outbreaks.

People in Nigeria’s northern Katsina state have not been as lucky. At the moment they are facing a measles epidemic which has killed nearly two hundred children in the past three months, and infected thousands.

What’s going on?
It seams that parents, for a variety of reasons, are fearful of giving their children vaccinations. For nearly everyone, the measles vaccination is safe and effective and if you want more information about the vaccine click here. Measles outbreaks aren’t very common in the U.S., fewer than 100 per year. But in the pre-vaccine era, 3-4 million measles cases occurred every year in the US. This resulted in approximately 450 deaths, 28,000 hospitalizations and 1,000 children with chronic disabilities from measles encephalitis each year. These two outbreaks in the US serve as a reminder that unvaccinated people remain at risk for measles and that measles spreads rapidly without proper controls.

According to the WHO, around the world measles still kills 250,000 people each year. Most of these deaths occur in undeveloped nations where people don’t have access to vaccinations and healthcare. But it appears the problem in both Austria and Nigeria are unvaccinated children. In Nigeria many parents are afraid to vaccinate as reported in the VOA:

Katsina state's director of disease control, Halliru Idris, tells VOA that the outbreak is mostly affecting young people who have not been immunized. "I can tell you that over 95 percent of all the children that have measles are those whose parents have not allowed them to receive immunization," he said.
A handful of radical Islamic clerics instigated a boycott of infant vaccinations in northern Nigeria in 2003 and 2004, alleging that immunization was a western ploy to render Muslim girls infertile. Though the dispute has been resolved, parents still tend to avoid immunization.

In Austria officials fear that school administrators at the private school where the outbreak began advised parents against vaccinating their students. An investigation is ongoing.

So what should we do?
In Iowa the public health response to one imported measles case cost approximately $150,000. Should parents who choose not to vaccinate their children be responsible for these expenses? How do we balance personal choice and the good of the community?

Jan
11
2008

Help me you ants: A new study shows that acacia trees in Africa need to have both the ants that protect them from predators and the predators themselves to thrive. Take away one component, and the trees themselves start to look sickly.
Help me you ants: A new study shows that acacia trees in Africa need to have both the ants that protect them from predators and the predators themselves to thrive. Take away one component, and the trees themselves start to look sickly.Courtesy Wikipedia
Mighty acacia trees tower and spread across the African skies. Little ants scramble about as a protective army. Without each other, they’re nothing.

That’s what ten years of research is confirming. Scientists have known for a long time about the symbiotic relationship between the big trees and the little bugs. The trees give the ants a place to live. The ants bite and pester large animals that try to eat the tree’s leaves and limbs.

But what happens when the conditions get reversed?

After ten years of study, we’re starting to get some answers.

With the numbers of large animals in Africa in decline, researchers thought they’d try to find out, on a limited scale, what the impact would be of fewer creatures bothering the acacia tree.

Fences were set up around some trees that prevented large animals from feasting on the trees.

Even after just a few years, the trees were looking rather ragged and their growth rates slowed down. What was going on?

The trees no longer had need to take care of the ants. They didn’t produce as much nectar that the ants feed on and they had fewer, smaller thorns for the ants to live in. Consequently, the ants started to abandon the trees for other locations, giving way to other insects that were damaging the trees.

While the original “mutualism” relationship developed over a long period of time, researchers point out that it can break down in a quick amount of time.

Researchers are going to take this experiment to one more level. They’re going to “reverse” the reverse process on some of the fenced trees, taking the fences down and seeing how quickly, if at all, the ants come back to the trees if the large animals start eating the trees’ greens.

What do you think of all of this? Share your thoughts here with other Science Buzz readers.

Wired Magazine has a feature on National Geographic's massive gene database project. They hope to track how humans have moved through the world by looking at mutations in our mother's DNA.

Aug
22
2005

It's older than the plague, typhoid fever, or malaria. It's claimed the lives of literary greats John Keats, Emily Bronte, and Franz Kafka, and kills more than three million people around the world each year by attacking the lungs and producing symptoms like coughing, loss of appetite, fever, and night sweats. Tuberculosis, caused by the bacterium Mycobacterium tuberculosis, is also re-emerging in areas like Eastern Europe, southeast Asia, and sub-Saharan Africa, where HIV is on the rise. Scientists now believe that TB may actually date back as far as three-million years, with current strains descended from a more ancient bacterial species that emerged in Africa. "Tuberculosis. . . might have affected early hominids," says researcher Veronique Vincent of the Institut Pasteur in Paris. Up until this point, scientists believed that TB arose a few tens of thousands of years ago and spread around the world. However, molecular analysis of a strain of TB from East Africa suggests that the disease is much, much older. Researchers hope this information will aid in the development of new treatments; Mycobacterium tuberculosis is rapidly growing resistant to the drugs currently used to treat it.