In a historic event, the world’s first malaria vaccine is approved by W.H.O. and will be tested in Kenya, Ghana, and Malawi.
The World Health Organization on Wednesday endorsed the vaccine in a historical first step in a method that should lead to wide distribution in poor countries. To have a malaria vaccine that is safe, moderately effective, and ready for distribution is “a historic event,” said Dr. Pedro Alonso, director of the W.H.O.’s global malaria program.
Dr. Tedros Adhanom Ghebreyesus, the World Health Organization’s director-general, said the long-awaited vaccine was a breakthrough for science and could save tens of thousands of young lives each year.
He said, “As some of you may know, I started my career as a malaria researcher, and I longed for the day that we would have an effective vaccine against this ancient and terrible disease. And today is that day — a historic day. Today, W.H.O. is recommending the broad use of the world’s first malaria vaccine. This recommendation is based on results from an ongoing pilot program in Ghana, Kenya, and Malawi that has reached more than 800,000 children since 2019. This long-awaited malaria vaccine is a breakthrough for science, child health, and malaria control. Using this vaccine, in addition to existing tools to prevent malaria, could save tens of thousands of young lives each year.
Malaria remains a tremendous health challenge in the world, infecting more than 200 million people every year and killing about half a million. Children in Africa are the most vulnerable. In 2015, 88 percent of global cases and 90 percent of global deaths occurred in Africa. While experts agree that the new vaccine is not yet up to the mark, it will help turn the tide. However, the challenge lies in delivering four doses of the vaccine for each child in poverty-stricken countries. For prevention, the countries rely on bed netting and insecticides.
Kenya, Ghana, and Malawi were chosen for the pilot program because they continue to have high numbers of malaria cases despite having strong prevention and vaccination programs. The vaccines will be tested on children five to 17 months old through the existing vaccination programs in each country.
Malaria is rare in the developed world. There are just 2,000 cases in the United States each year, mostly among travelers returning from countries in which the disease is endemic.
The vaccine, called Mosquirix, is not just a first for malaria — it is the first developed for any parasitic disease. Parasites are much more complex than viruses or bacteria, and the quest for a malaria vaccine has been underway for a hundred years.
“It’s a huge jump from the science perspective to have a first-generation vaccine against a human parasite,” Dr. Alonso said.
In clinical trials, the vaccine had an efficacy of about 50 percent against severe malaria in the first year, but the figure dropped close to zero by the fourth year. And the trials did not directly measure the vaccine’s impact on deaths, which has led some experts to question whether it is a worthwhile investment in countries with countless other intractable problems.
But critical malaria cases accounts for up to half of the malaria deaths and is considered “a reliable proximal indicator of mortality,” said Dr. Mary Hamel, who leads the W.H.O.’s malaria vaccine implementation program. “I do expect we will see that impact.”
A modeling study last year estimated that if the vaccine were rolled out to countries with the highest incidence of malaria, it could prevent 5.4 million cases and 23,000 deaths in children younger than 5 each year.
A recent trial of the vaccine in combination with preventive drugs given to children during high-transmission seasons found that the dual approach was much more effective at preventing severe disease, hospitalization, and death than either method alone.
The malaria parasite, carried by mosquitoes, is a particularly sneaky lethal enemy because it can strike the same person over and over. In many parts of sub-Saharan Africa, even those where most people sleep under insecticide-treated bed nets, children have on average six malaria episodes a year.
Even when the disease is not fatal, the repeated assault on their bodies can permanently alter the immune system, leaving them weak and vulnerable to other pathogens.
A nurse discussed the new malaria vaccine at the Ewim Polyclinic in Cape Coast, Ghana. More than 2.3 million doses have been administered, reaching more than 800,000 children.
A nurse discussed the new malaria vaccine at the Ewim Polyclinic in Cape Coast, Ghana.
Malaria research is jumbled with vaccine candidates that never made it past clinical trials. Bed nets, the most widespread preventive measure, cut malaria deaths in children under 5 only by about 20 percent.
Against that backdrop, the new vaccine, even with modest efficacy, is the best new development in the fight against the disease in decades, some experts said.
“Progress against malaria has really stalled over the last five or six years, particularly in some of the hardest-hit countries in the world,” said Ashley Birkett, who heads malaria programs at PATH, a nonprofit organization focused on global health.
With the new vaccine, “there’s potential for very, very significant impact there,” Dr. Birkett said.
Mosquirix is given in three doses between ages 5 and 17 months, and a fourth dose roughly 18 months later. Following clinical trials, the vaccine was tried out in three countries — Kenya, Malawi and Ghana — where it was incorporated into routine immunization programs.
More than 2.3 million doses have been administered in those countries, reaching more than 800,000 children. That bumped up the percentage of children protected against malaria in some way to more than 90 percent, from less than 70 percent, Dr. Hamel said.
“The ability to reduce inequities in access to malaria prevention — that’s important,” Dr. Hamel said. “It was impressive to see that this could reach children who are currently not being protected.”
It took years to create an efficient system to distribute insecticide-treated bed nets to families. By contrast, including Mosquirix among routine immunizations made it surprisingly easy to distribute, Dr. Hamel added — even in the midst of the coronavirus pandemic, which prompted lockdowns and disrupted supply chains.
“We aren’t going to have to spend a decade trying to figure out how to get this to children,” he said.
This week, a working group of independent experts in malaria, child health epidemiology, and statistics, as well as the W.H.O.’s vaccine advisory group, met to review data from the pilot programs and to make their formal recommendation to Dr. Tedros Adhanom Ghebreyesus, director-general of the W.H.O.
“We still have a very long road to travel, but this is a long stride down that road,” Dr. Tedros said at a news conference on Wednesday.