Protective immunity

Every year approximately a million people die from malaria, a treatable blood disease, and most of those who die are children under the age of five. "A new vaccine to prevent the deadly malaria infection has shown promise to protect the must vulnerable patients--young children--against the disease."

The results found by the international research team, led by the University of Maryland School of Medicine's Center for Vaccine Development (CVD) and the Malaria Research and Training Center at the University of Bamako in Mali, excites the medical community. "In a new study of the vaccine in young children in Mali, researchers found it stimulated strong and long-lasting immune responses. In fact, the antibody levels the vaccine produced in the children were as high or even higher than the antibody levels found in adults who have naturally developed protective immune responses to the parasite over lifelong exposure to malaria."

"In areas of the world such as Africa, where malaria is particularly rampant, the young are most vulnerable to the disease since they have not built up the same natural immunity as adults. A child dies of malaria every 30 seconds, according to the World Health Organization. There are about 300 million malaria cases worldwide each year, resulting in more than one million deaths, most of them African children."

Malaria is a parasite, "spread to humans through mosquito bites". At this time, "no approved vaccine to protect against the condition" exists, although "using bed nets or killing mosquitoes with insecticides can prevent infection. The parasite is treatable using medications, though drug resistance is a relatively common problem. Eradicating the disease has become a priority for scientists and health officials worldwide. An effective and broadly protective vaccine is a key step toward that goal."

This "vaccine, based on a single strain of the falciparum malaria parasite -- the most common and deadliest form of the parasite found in Africa -- targets malaria in the blood stage. The blood stage is the period after the mosquito bite, when the parasite multiplies in the blood, causing disease and death." Before this discovery, "other blood stage vaccines" existed, but none of them exhibited "the ability to prevent malaria disease."

In addition to preventing malaria, the vaccine (at all three tested doses) "proved to be safe and well tolerated" in each of the 100 Malian children administered with the drug. A new trial is already planned to test more subjects and to examine "whether the vaccine -- though it is based on a single strain of malaria -- can protect against the broad array of malaria parasites that exist."

Sources:
University of Maryland Medical Center (2010, February 6). New malaria vaccine is safe and protective in children, scientists find. ScienceDaily. Retrieved February 6, 2010, from http://www.sciencedaily.com­ /releases/2010/02/100203201425.htm