The RTS,S malaria vaccine, incorporated into routine immunization programs in several African nations, is showing positive impacts in reducing severe illness and deaths among young children, but challenges persist in ensuring full adherence to the multidose regimen.
In Cameroon, where the RTS,S vaccine was introduced more than two years ago, health workers report a noticeable decrease in pediatric cases. Mabel Djoumessi, a mother in central Cameroon, attributes her 9-month-old son Kenfack's good health to the vaccine, contrasting it with the frequent illnesses of her older children who did not receive it. "My other children who have never taken the vaccine frequently fall ill," Djoumessi said. "My son... has never had it."
Data from Cameroon's National Malaria Control Program indicates a reduction in malaria cases, with 33,000 fewer recorded in 2025 compared to the previous year. However, officials caution against attributing this decline solely to the vaccine. Dr. Bomba Amougou, head of prevention at the program, stated that while the vaccine has contributed, isolating its specific impact requires further modeling. "It is accurate to say that the vaccine has contributed to the reduction in cases and deaths, rather than being the exclusive cause," he noted.
Malaria remains a significant threat, particularly for children under five, with Africa bearing the brunt of global cases and deaths. The World Health Organization recommended the wider use of RTS,S in 2021, following pilot studies in Ghana, Kenya, and Malawi, which found it reduced deaths by 13%. The newer R21 vaccine has also shown efficacy, reducing clinical malaria cases by over 50% in the first year after three doses in clinical trials.
Despite the vaccine's availability, ensuring children complete the full four-dose course is a challenge. In a pilot program across 158 districts in Ghana, Kenya, and Malawi, initial vaccination coverage reached about 80% for the first dose, but dropped to 46% for the fourth dose, administered around 22-24 months of age. In Cameroon, first-dose coverage rose from 66% to 68% between 2024 and 2025, with third-dose coverage reaching 59%. However, fourth-dose coverage stood at only 25% as of 2025.
Health workers attribute the lower uptake of the final dose to several factors, including parental and health worker forgetfulness, especially given the long interval between the third and fourth shots. Competing responsibilities, transport costs, and lack of reminders also contribute to missed appointments, according to studies of the vaccine rollout.
"When my son turns 2, I will make sure I come for the fourth dose," Djoumessi affirmed. "I don’t want him to suffer like the others."
Dr. Sania Nishtar, CEO of Gavi, the Vaccine Alliance, acknowledged these as "initial teething problems" that should not overshadow the vaccine's value. She highlighted that parental acceptance of the malaria vaccine is high due to the urgency of preventing child deaths from the disease, leading to significant demand from governments and communities.
Over 52 million doses have been distributed to 25 high-risk African countries with Gavi's support. However, Gavi has cited foreign aid cuts as a "stark constraint" on the rollout, though the organization continues to guarantee vaccine supply for up to 70% of eligible children in low-income countries.
Cameroon and other nations have initiated "Big Catch-up" campaigns to encourage timely vaccinations. For many families, the vaccine also represents a reprieve from substantial medical expenses. Georgette Caroline Mengbwa, a mother of three, noted that her unvaccinated children fall ill every few months, costing her between $53 and $107 each time, a significant sum in a country with a monthly minimum wage of about $76.
Experts emphasize that the malaria vaccine is most effective when it complements other preventive measures, such as bed nets, prompt treatment, and good sanitation. Research continues toward developing a single-dose vaccine, which would likely improve administration and uptake.