English
Malaria: The Good News, The Bad News
Posted on May 14, 2013 by Ailee Slater (G+)
Mosquitoes. Barely larger than a kidney bean and yet responsible for more than half a million deaths every year. Why? Because mosquitoes carry malaria.
There is no malaria vaccine, and it is not possible to eradicate every insect carrier from the face of the earth. These facts alone make malaria an important issue in the world of science and health care, but recently, malaria has been getting even more media coverage - both in terms of positive scientific developments, as well as threatening trends in drug-resistant malaria infections.
One of the most exciting bits of recent malaria news was published this month in the journal Science, and detailed the findings of one American research team. The team has been experimenting with a type of bacteria known as the Wolbachia bacterium. This bacteria is special, because when a mosquito is infected with Wolbachia, the insect will become resistant to malaria. Similar to the use of probiotic bacteria in humans, Wolbachia helps mosquitoes fight off other, more harmful bacteria, such as that leading to malaria infections.
However, there is one major problem with the Wolbachia bacterium - it doesn't stick around. The bacteria can be transferred to a mosquito, but will soon leave the insect's body. When the Wolbachia bacterium has disappeared from the mosquito, all the protective effects of the bacteria disappear as well, leaving the mosquito once again vulnerable to contracting and spreading malaria.
Luckily, the aforementioned malaria research team has found a way to make the Wolbachia bacterium last longer. These scientists have developed an innovative method of creating an entirely new type of mosquito, then putting this insect into the general population to mate and spread its unique DNA. This DNA has been designed by the scientists to carry the Wolbachia bacterium. These specially-designed mosquitoes are therefore resistant to malaria, and will pass on those genes to offspring. With these new insects, an entire population of mosquitoes could become malaria-free in just a few generations.
Of course, more work is still needed to put this Wolbachia research into use. One problem is that these malaria-resistant mosquitoes reproduce more slowly than normal mosquitoes, and so unless scientists can overcome the fragility of Wolbachia mosquito eggs, the use of this bacterium in preventing malaria may be limited.
Another recent development in the world of malaria research concerns malaria treatment in humans. Right now, the most effective form of malaria treatment is an herbal compound known as artemisinin. This compound comes from the wormwood plant, and is extremely useful for its naturally occurring anti-malarial properties. Nearly all cases of malaria will be treated with some form of artemisinin.
The problem with artemisinin, however, is that the price of this herbal compound has been extremely unstable. As global demand for artemisinin has increased, prices have risen greatly - in 2003, the compound sold for around USD $100 per pound; by the end of 2004, the cost per pound was more than $500. Since that leap, the cost of artemisinin has both risen and fallen, leading to a situation wherein affordable access to the drug cannot be guaranteed.
To help more malaria victims, many of whom cannot afford expensive artemisinin drugs, scientists have for years been working to develop a synthetic version of the artemisinin compound; one that does not come from the wormwood plant, and will not be subject to the same price fluctuations. Researchers in California reported this month that they have found a new method of creating synthetic artemisinin, utilizing baker's yeast. A full summary of these scientists' findings and methods is available here.
The process of creating a synthetic version of artemisinin was not easy; indeed, researchers working on the project have commented that the likelihood of developing a usable, non-natural artemisinin compound was very slim. Now that the project has achieved success, scientists and health care workers are excited about the possibility of soon getting new anti-malaria drugs on the market; drugs that can treat malaria, and be produced and sold in a more cost-effective manner.
Unfortunately, these excellent developments in malaria research highlight the dangers of the disease; especially when the illness becomes resistant to drugs. Drug-resistant strains of malaria are on the rise in Southeast Asia especially, due in large part to political instability and a strong counterfeit drug market in Burma.
Malaria treatment drugs in Burma can be bought and sold without a prescription, and to save money, many people will purchase these treatments on the black market. Unfortunately, unregulated and counterfeit malaria drugs are often just sugar pills containing a very small amount of an anti-malarial ingredient, such as artemisinin. When a person infected with malaria takes these counterfeit drugs, the anti-malarial ingredient will not be potent enough to cure the infection; even worse, the microorganisms not destroyed by the drug treatment will grow stronger, creating a new malaria strain that is resistant to the drugs to which it has been exposed.
The issue of counterfeit malaria drugs is also affecting the Congo; a nation where, according to some research, nearly half of all anti-malarial drugs on the market are ineffective. This is an especially pressing issue for an African country, because the continent of Africa accounts for more than 90 percent of all malaria deaths. According to the World Health Organization, an African child dies from malaria once every minute.
Still, researchers are aware of the counterfeit drug problem and working hard to combat it. The National Public Radio news service in America recently published a story about an Italian researcher studying mosquitoes on the Thai-Burmese border, and working to develop a new drug that will fight malaria before symptoms of the infection manifest. Malaria will normally become evident around ten days after an individual has been bitten by an infected mosquito. If malaria treatment can begin before symptoms appear, people will be less likely to seek out counterfeit medication, and drug-resistant malaria should decrease.
Malaria is an illness with many challenges, and yet new research indicates that there are many reasons to be hopeful that by the time we celebrate World Malaria Day on April 25th next year, we will have seen even more promising global developments in preventing and treating the disease.