Malaria, a parasitic disease spread by infected mosquitoes, continues to be a significant global health challenge. After extensive research and development efforts, effective malaria vaccines have been developed and are now being deployed in regions where the disease burden is highest.
The Approved Malaria Vaccines
The World Health Organization (WHO) has recommended two malaria vaccines: RTS,S/AS01 (Mosquirix) and R21/Matrix-M. These are the first vaccines developed to target a human parasitic disease. Both vaccines work by targeting the Plasmodium falciparum parasite, its sporozoite stage, which enters the human bloodstream after a mosquito bite.
The vaccines stimulate the immune system to produce antibodies against the circumsporozoite protein (CSP) on the parasite’s surface. This early immune response prevents sporozoites from reaching and infecting liver cells, stopping the parasite’s life cycle. RTS,S/AS01 was developed by GlaxoSmithKline and PATH Malaria Vaccine Initiative, while R21/Matrix-M was developed by the University of Oxford and manufactured by the Serum Institute of India. The R21 vaccine incorporates Novavax’s Matrix-M adjuvant technology to enhance the immune response.
Target Populations and Global Rollout
Malaria vaccination primarily targets young children under five years old residing in areas with moderate to high malaria transmission, predominantly in sub-Saharan Africa. Malaria disproportionately affects children in this region, where nearly half a million children die from the disease each year. The WHO coordinates the global rollout programs, with support and funding from partners like Gavi, the Vaccine Alliance.
Since 2019, the RTS,S vaccine has been delivered to millions of children in countries like Ghana, Kenya, and Malawi through the Malaria Vaccine Implementation Programme (MVIP). In 2024, the rollout expanded, with 17 countries in Africa beginning to offer malaria vaccines through their routine childhood immunization programs. The R21 vaccine also began its rollout in 2024, with the Central African Republic among the first to receive doses for routine immunization. Due to limited initial supply and the overwhelming burden of malaria in endemic regions, these vaccines are not currently recommended for travelers or tourists. Other established preventive measures remain suitable for short-term exposure.
Vaccine Efficacy and Public Health Impact
Clinical trials and pilot programs provide data on the efficacy of both recommended malaria vaccines. The RTS,S/AS01 vaccine significantly reduces severe malaria cases and hospitalizations in young children. In real-world settings, the pilot program for RTS,S demonstrated a 13% reduction in all-cause mortality among age-eligible children.
The R21/Matrix-M vaccine has demonstrated higher efficacy rates in its trials. In areas with highly seasonal malaria transmission, R21 reduced symptomatic malaria cases by 75% within 12 months following a three-dose series. A booster dose given a year later maintained this protection. While efficacy numbers can vary based on study design and transmission intensity, both vaccines are considered effective tools. Modelling estimates suggest the R21 vaccine could avert 180,000 to 200,000 clinical cases and 630 to 650 deaths per 100,000 vaccinated children over 15 years in different transmission settings.
Role in an Integrated Prevention Strategy
The malaria vaccine is one component within a broader, integrated strategy for malaria prevention and control. It is an additional tool to be used alongside existing interventions. Combining these efforts maximizes protection against the disease.
Other established measures remain important, including the consistent use of insecticide-treated bed nets (ITNs), which can reduce the risk of contracting malaria by more than 50%. Indoor residual spraying (IRS), another vector control method, involves applying insecticides to the inner surfaces of homes to kill mosquitoes. Access to rapid diagnostic tests and effective antimalarial treatments also plays a significant role in managing cases and preventing severe outcomes. Continuing to implement these interventions alongside vaccine deployment is important to sustain progress toward reducing malaria burden and moving closer to elimination goals.