As of May 8, 2026, researchers have proof of what many hoped but few dared believe: the RTS,S malaria vaccine saves children's lives in the real world. A study published in The Lancet by the World Health Organization shows that in the first three countries with routine vaccination, one in eight eligible children avoided death because they were vaccinated. For the first time, a malaria vaccine demonstrates measurable impact under everyday health conditions, even when fewer than half of children in pilot countries received all four recommended doses.
What the Lancet study reveals
The results stem from four years of observation of the WHO pilot program in Ghana, Kenya, and Malawi, the first three countries to introduce RTS,S into their national immunization programs in 2019. The research team, working with the London School of Hygiene and Tropical Medicine, analyzed mortality and hospital admission data for children across dozens of health districts and compared them with districts without vaccination programs.
The May 2026 Lancet findings: overall child mortality in the vaccinated age group declined by 13 percent. Severe malaria cases requiring hospitalization dropped by 21.6 percent. Measured by lives saved, one in eight vaccinated children was spared from death.
Particularly significant: this protection occurred even though only 71 percent of children received all three primary vaccinations and roughly 40 percent received the recommended fourth dose. Earlier concerns that incomplete vaccination coverage would eliminate the vaccine's effectiveness are contradicted by the study. RTS,S protects measurably even without a complete series. The WHO called the results a milestone that researchers have waited decades to see.
From pilot to routine: 25 countries deployed
Since 2019, the number of countries using the vaccine has grown from three to 25. This includes nine of the ten countries with the highest malaria burden globally. In 2025, 28.3 million doses were distributed, a 169 percent increase from the previous year. Gavi, the vaccine alliance, plans to reach at least 50 million children with malaria vaccines by 2030.
Early data from recently adopting countries confirm the vaccine's impact. In Burkina Faso, which introduced the vaccine in February 2024, national malaria cases fell from 10.8 million to 7.3 million, a 32 percent decline. In Cameroon, health facilities recorded roughly 17 percent fewer confirmed malaria cases in 2025 than the prior year.
Complementing RTS,S is R21, a second malaria vaccine developed by the University of Oxford and the Serum Institute of India, which achieved over 75 percent efficacy in clinical trials and has been deployed in several African countries since 2024. Both vaccines work alongside established interventions: insecticide-treated bed nets, artemisinin-based combination therapies, and rapid diagnostic tests. Together, they form the most comprehensive protection package ever deployed against malaria.
Context: other vaccine milestones
To put this in perspective, consider other vaccine achievements. Polio was endemic in more than 125 countries in 1988 with approximately 350,000 estimated cases annually. Through global vaccination campaigns, cases dropped to fewer than 200 in two remaining endemic countries, Pakistan and Afghanistan. This represents more than 99 percent reduction according to the WHO. Malaria is structurally more difficult than polio: Plasmodium falciparum is a parasite with a complex life cycle, not a virus. Complete eradication is far harder to achieve.
Another comparison: smallpox. In 1967, the WHO recorded 10 to 15 million cases globally. On May 8, 1980, the World Health Assembly declared the disease eradicated. Behind this unique success was a vaccine with approximately 95 percent protective efficacy and an eradication strategy spanning decades. RTS,S does not achieve such complete protection, but smallpox too was not conquered by a miracle cure but through sustained campaigns over many decades.
What matters: malaria killed an estimated 438,000 children under five in Africa in 2024, according to the WHO World Malaria Report 2025. If RTS,S delivers the same impact at scale as shown in pilot studies, mathematically tens of thousands of child lives per year could be saved. Burkina Faso and Cameroon show this is not theoretical.
Three obstacles to wider success
Despite this success, three factors threaten the rollout at scale.
First is funding. The introduction of vaccines in 25 countries was largely financed by the Global Fund, Gavi, and US development aid. Since the Trump administration began, US development aid spending has been drastically cut, including malaria programs in Africa. Gavi has internally warned that plans to reach at least 50 million children by 2030 are jeopardized by these funding gaps.
Second is the fourth dose. While RTS,S protects without a full fourth dose, protection is demonstrably weaker. In pilot studies, fewer than half of children received this fourth dose, given at 22 to 24 months of age, when many families lose contact with health services. Systematic investment in follow-up and reminder systems is necessary but not automatic.
Third is artemisinin resistance. The WHO World Malaria Report 2025 documents growing resistance of the malaria parasite to artemisinin-based therapies in at least eight African countries. This resistance does not affect the vaccine itself, which works through a different mechanism. It does affect treatment of those in whom vaccine protection fails. As standard treatments lose effectiveness, the burden of severe and fatal malaria rises.
The vaccine alone cannot defeat malaria. But it has proven it saves lives. Whether these results drive the necessary expansion depends less on science than on political decisions about funding and priorities.