DODOMA, Tanzania — Malaria was known as a kiss of death throughout ancient cultures, but was not identified as a parasitic disease until French surgeon Charles Louis Alphonse Laveran noticed parasites in his patients’ blood in 1880 while stationed in Algeria. Although the risk of malaria among African populations has declined due to simple solutions such as mosquito nets and insecticides, in 2012 alone it killed more than 600,000 people, 90 percent of them in Sub-Saharan Africa and less than five years old. On average, malaria kills a one child per minute, which makes it the most deadly infectious disease in the world for children less than five years old.
Finding a malaria vaccine has stumped scientists and researchers since its discovery. The parasite that causes malaria is known as Plasmodium, which, once inside the bloodstream, travels to the liver, multiplies by the tens of thousands, then returns to the bloodstream. Throughout different stages of the parasite’s cycle, it produces different proteins, making it nearly impossible for a vaccine to have a solid target. As tricky as the plasmodium parasite is, a research team from Brown University School of Medicine has just made a breakthrough in a new vaccination.
A study was conducted with about 1,000 children in Tanzania in the early years of their lives (when resistance to malaria develops in the immune system) and six percent of the children developed a natural immunity to malaria. The research team then studied the antibodies in the malaria-resistant group in order to extract a key difference and explanation for their immunity.
The team found that the antibody in the resistant children traps the malaria parasite in the shizont stage in red blood cells, where it fights the PfSEA-1 protein, the one responsible for spreading the parasite from one red blood cell to another. Because of this, the parasite cannot spread throughout the body. From here, the infected red blood cells are vulnerable to the immune system.
A similar study was done among adolescents in Kenya, and those found with the same antibodies correlated with those resistant to malaria.
“We’ve found a way to block it from leaving the cell once it has entered. It can’t go anywhere. It can’t do any further damage,” said Doctor Jonathan Kurtis, director of the center for International Heath Research and the spokesman for the research team. “We’re sort of trapping the parasite in the burning house.”
The malaria vaccine created was tested on mice, where the mice with the treatment lived twice as long as the control group, and had one-fourth the amount of parasites. The following step is to test the vaccine on primates, then progress into human trials. The National Institute of Allergy and Infectious Diseases team wishes for their vaccine to be ready for trials within 18 months.
Since the new malaria vaccine just focuses on halting the spread of the parasite, scientists are planning on combining it with existing vaccines aimed at different parts of the parasitic cycle in hopes of creating something that can wipe out the virus completely.