Controlling malaria has long been a top goal of international public-health authorities. Caused by parasites transmitted by infected mosquitoes, malaria annually sickens more than 200 million people and kills nearly 800,000, mostly children in Africa. Because children are the most vulnerable to the disease, efforts to develop a vaccine have focused on them.
While far less protective than vaccines used against other diseases, the results of the test vaccine were hailed as a major advance.
“This is remarkable when you consider that there has never been a successful vaccine against a human parasite,” Tsiri Agbenyega of the Komfo-Anokye Hospital in Ghana, who is leading the study, told reporters during a briefing before the results were made public. “This potentially translates into tens of millions of cases of malaria in children being averted.”
Beyond causing disease and deaths, malaria saps many developing nations’ economies, accounting for 40 percent of medical costs, up to half of all hospitalizations and 60 percent of all visits to health clinics. Although it has largely been eliminated from most developed parts of the world, half of the world’s population live in areas where malaria remains endemic. It is the fifth leading cause of death from an infectious disease worldwide, the second leading cause of death in Africa and the leading cause of death in Africa among children younger than 5.
Bed nets treated with insecticide have reduced infections, but efforts to produce an effective malaria vaccine for children and adults have been repeatedly stymied. It is much more difficult to produce a vaccine against a parasite than against a virus, and the malaria parasite morphs its form at various stages in an infected person’s body.
Several experimental vaccines are being developed, but the one tested in the study is the most promising and by far the furthest along in development.
The vaccine’s developers hope to use the results of the study to win regulatory approval for the vaccine and make it available as soon as 2015. GlaxoSmithKline, which makes the vaccine, has pledged to sell it at an affordable price, charging just 5 percent above cost, and to work with suppliers to reduce the cost; to use any profit to develop a second-generation malaria vaccine; and to conduct research on other diseases that plague the developing world.
“Our intention is to supply this vaccine at the lowest cost possible,” said Glaxo’s chief executive, Andrew Witty. “We have no intention of making a profit here.”