Duquesne Scientist Wages Battle Against an Ancient and Modern-Day Enemy: Malaria
Far from the dry and rainy seasons of the tropics, Dr. David Lampe is working in his Mellon Hall lab on Duquesne University's campus to fight one of the world's most prominent and deadly infectious diseases: malaria.
About half of the world's population is at risk for malaria, with the largest group being African children, said Lampe, associate professor of biological sciences in the Bayer School of Natural and Environmental Sciences. Malaria kills an estimated 1 million people every year-and many who don't die are severely debilitated in some of the poorest places on Earth.
"We've been contracting malaria as long we we've been a species," said Lampe, who is among the scientists working to turn the tide, which is actually gaining on humans.
The deadly disease is carried by some of the hundreds of species of Anopheles mosquitoes-but only by the blood-sucking females. If the females carry the protozoan parasite-which spends part of its life cycle developing inside the mosquito and is responsible for causing the disease-they can transmit the parasite along with their bites. Scientists have fought the disease in two ways: killing the insects that carry malaria with insecticides or killing the parasites, once they are in humans, with drugs.
Drug resistance is evolving among the parasites; insecticide resistance is evolving among the mosquitoes. While the Bill and Melinda Gates Foundation and the World Health Organization have made progress on a vaccination, that approach is far from 100 percent effective.
"It's pretty clear that any effort to eradicate malaria is not going to succeed with one method of control," said Lampe, whose work has been funded through the Commonwealth of Pennsylvania and the National Institutes of Health's National Institute of Allergy and Infectious Diseases, as well as the Gates Foundation.
Lampe and his collaborators, whose work was published in July in the prestigious Proceedings of the National Academy of the Sciences, harness symbiotic bacteria that normally live in Anopheles mosquitoes. They genetically altered these bacteria to produce proteins that kill the malaria parasite, Plasmodium falciparum, before it can reproduce in the mosquito. Because the parasite spends much of its life cycle inside the gut of the mosquito, it cannot escape exposure to the genetically modified bacteria and its toxin.
The bacteria can be fed in water to mosquitoes when they are in the larval stage, Lampe explained; in the field, "mosquito feeders" could be used to attract the insects and the genetically modified bacteria would naturally reproduce on its own as well.
"In addressing an important international health priority, Dr. Lampe's work emphasizes not only the high quality and impact of our research programs," said Dean David W. Seybert, "but it also demonstrates the Bayer School's mission of advancing scientific knowledge to benefit our global society."
Facts about Malaria
- Fact: Malaria cannot be contracted through the environment.
Malaria must be in the bloodstream to be contracted and an unborn baby can be infected by its mother. The disease infects red blood cells.
- Fact: Different types of malaria affect humans, rodents, reptiles and birds.
Dr. David Lampe is working with a strain of rodent malaria calledPlasmodium berghei.
- Fact: An estimated 300 million to 500 million cases of malaria occur every year.
About 1 million deaths, mostly African children, are attributed to malaria each year.
- Fact: Resistance is an issue in both the disease-causing parasite and the mosquitoes that carry it.
The parasite is evolving resistance to drugs used to fight the disease, while the Anopheles mosquitoes also are evolving resistance to insecticides used to kill them. That's why Lampe and his collaborators are focusing on indirectly destroying the parasites with the protein of a genetically modified bacterium.
Source: U.S. National Library of Medicine