March 24, 2010, 11:13 a.m.
Two years ago, Melinda and I challenged the health field to set a goal of eventually eradicating malaria. Because it is such a widespread disease, the foundation has backed a number of different types of innovations. In 2005 we helped fund a medium-risk pilot project in Zambia to test having most people in an area sleep under insecticide-treated bed nets and spray the inside of their house with insecticides. These interventions have proven to reduce malaria substantially, and other partners have now taken the lead on the large-scale delivery of these interventions. There has been a dramatic increase in bed net usage thanks to donations from individuals (some through church organizations and Nothing But Nets), The Global Fund, and rich governments. The countries that have had these interventions in wide-scale use for several years are seeing large reductions in malaria deaths: Rwanda has seen a 45 percent decline, Zambia 50 percent, Cambodia 50 percent, Eritrea 80 percent. These interventions are being scaled up rapidly, which will have a big impact.
But malaria is a particularly tricky disease. The current tools alone will not be enough to eradicate it, so we are funding new medium- and high-risk innovations. For example, we are funding the invention of new insecticides for use on bed nets, because some mosquitoes are developing resistance to the current one. And because bed nets aren’t accepted in some locations, we are also investing in new ways of delivering insecticide in a house—perhaps using candles or chemical sticks. We are also investing in cheaper ways to make the drugs we already have, as well as new drugs because we know the parasite will develop resistance to the current treatments.
Finally, to eradicate the disease, we will almost certainly need a malaria vaccine, which is the highest-risk malaria work we fund. The key here is that researchers are pursuing a lot of different ideas, so that if one fails, there are still several other options. One partially effective vaccine candidate, known as RTS,S, has started its Phase III trial, which is an important step. Other vaccine approaches are at an earlier stage and they also look very promising. Scientists are combining some of these other vaccine efforts with RTS,S to raise its effectiveness and duration, an approach that could lead to a highly efficacious vaccine in 8 to 15 years.