Explained: What is Mosquirix, the first malaria vaccine to get the WHO’s backing?

This is the first malaria vaccine that has completed the clinical development process, and received a positive scientific opinion from the European Medicines Agency (EMA).

Health officials prepare to vaccinate residents of the Malawi village of Tomali, where young children become test subjects for the world's first vaccine against malaria. (AP Photo)

RTS,S/ASO1 (RTS.S), trade name Mosquirix, which was endorsed by the World Health Organisation (WHO) on Wednesday (October 6), is the first and, to date only, vaccine shown to have the capability of significantly reducing malaria, and life-threatening severe malaria, in tests on young African children.

The vaccine acts against P. falciparum, the most deadly malaria parasite globally, and the most prevalent in Africa. Among children who received 4 doses in largescale clinical trials, the vaccine was able to prevent approximately 4 in 10 cases of malaria over a 4-year period.

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This is the first malaria vaccine that has completed the clinical development process, and received a positive scientific opinion from the European Medicines Agency (EMA).

It is also the first malaria vaccine to be introduced by three national ministries of health through their childhood immunization programmes — more than 800,000 children in Ghana, Kenya, and Malawi have been vaccinated, and are benefiting from the added protection provided by the vaccine as part of a pilot programme.

Other recent clinical evidence shows that strategic delivery of the vaccine just prior to the high malaria transmission season in areas where malaria is highly seasonal can optimize impact and markedly reduce mortality, especially when combined with other recommended malaria control interventions.

The global burden of malaria

Malaria is a life-threatening disease caused by parasites that are transmitted to people through the bites of infected female Anopheles mosquitoes. It is preventable and curable.

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Still, in 2019, there were an estimated 229 million cases of malaria worldwide, and the estimated number of malaria deaths that year stood at 409,000.

Children aged under 5 years are the most vulnerable group affected by malaria; in 2019, they accounted for 67% (274,000) of all malaria deaths worldwide.

In 2019, India had an estimated 5.6 million cases of malaria compared to about 20 million cases in 2000, according to WHO.

How the vaccine can help

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WHO’s recommendation is based on the advice of its two global advisory bodies, one for immunization and the other for malaria.

WHO has recommended that in the context of comprehensive malaria control, the RTS,S/AS01 malaria vaccine be used for the prevention of P. falciparum malaria in children living in regions with moderate to high transmission as defined by it.

The malaria vaccine should be provided in a schedule of 4 doses in children from 5 months of age for the reduction of malaria disease and burden.

The next steps for the WHO-recommended malaria vaccine will include funding decisions from the global health community for broader rollout in endemic countries, and country decision-making on whether to adopt the vaccine as part of national malaria control strategies.

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A vaccine is a breakthrough addition to the malaria toolkit and can help get malaria control back on track.

A baby from the Malawi village of Tomali is injected with the world’s first vaccine against malaria in a pilot program. (AP Photo/Jerome Delay, file)

Countries that have eliminated malaria

Globally, the elimination net is widening, with more countries moving towards the goal of zero malaria. In 2019, 27 countries reported fewer than 100 indigenous cases of the disease, up from 6 countries in 2000.

Countries that have achieved at least 3 consecutive years of zero indigenous cases of malaria are eligible to apply for the WHO certification of malaria elimination. Over the last two decades, 11 countries have been certified by the WHO Director-General as malaria-free: United Arab Emirates (2007), Morocco (2010), Turkmenistan (2010), Armenia (2011), Sri Lanka (2016), Kyrgyzstan (2016), Paraguay (2018), Uzbekistan (2018), Algeria (2019), Argentina (2019), and El Salvador (2021).

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Anuradha Mascarenhas

Anuradha Mascarenhas is a Senior Editor at The Indian Express, based in Pune. With a career spanning three decades, she is one of the most respected voices in Indian journalism regarding healthcare, science and environment and research developments. She also takes a keen interest in covering women's issues . Professional Background Education: A gold medalist in Communication and Journalism from Savitribai Phule Pune University and a Master’s degree in Literature. Author: She authored the biography At The Wheel Of Research, which chronicles the life and work of Dr. Soumya Swaminathan, the former Chief Scientist at the WHO. Key Focus: She combines scientific accuracy with storytelling, translating complex medical research into compelling public and human-interest narratives. Awards and Recognition Anuradha has won several awards including the Press Council of India's national award for excellence in journalism under the gender based reporting category in 2019 and the Laadli Media award (gender sensitivity -2024). A recipient of the Lokmat journalism award (gender category-2022), she was also shortlisted for the RedInk awards for excellence in journalism-2021. Her debut book At The Wheel Of Research, an exclusive biography of Dr Soumya Swaminathan the inaugural chief scientist of World Health Organisation was also nominated in the Popular Choice Category of JK Paper AUTHER awards. She has also secured competitive fellowships including the Laadli Media Fellowship (2022), the Survivors Against TB – New Research in TB Media Fellowship (2023) and is part of the prestigious 2025 India Cohort of the WomenLift Health Leadership Journey.” Recent Notable Articles (Late 2025) 1. Cancer & Specialized Medical Care "Tata Memorial finds way to kill drug-resistant cancer cells" (Nov 26, 2025): Reporting on a breakthrough for triple-negative breast cancer, one of the most aggressive forms of the disease. Discipline, diet and purpose; How a 97-year-old professor defies ageing'' (Nov 15, 2025) Report about Prof Gururaj Mutalik, the first Head of Department at Pune's B J Government Medical College who at 97 credits his longevity to healthy habits and a strong sense of purpose. 2. Environmental Health (The "Breathless Pune" Series) Long-term exposure even to 'moderate' air leads to chronic heart, lung, kidney issues" (Nov 26, 2025): Part of an investigative series highlighting that even "safe" pollution levels are damaging to vital organs. "For every 10 µg/m3 increase in PM2.5 level, there was 6-8% jump in medicine sales" (Nov 23, 2025): Using commercial data to prove the direct link between air quality and respiratory illnesses in Pune. 3. Lifestyle & Wellness News "They didn't let cancer, diabetes and heart disease stop them from travelling" (Dec 22, 2025): A collaborative piece featuring survivors who share practical tips for traveling with chronic conditions. At 17, his BP shot up to 200/120 mmHG; Lancet study flags why child and teen hypertension doubled between 2000 and 2020'' (Nov 12,2025)--A report that focusses on 17-year-old-boy's hypertensive crisis and reflects the rising global trend of high blood pressure among children and adolescents. 4. Scientific Recognition & Infrastructure For promoting sci-comm, gender diversity: IUCAA woman prof highlighted in Nature" (Nov 25, 2025): Covering the global recognition of Indian women scientists in gender studies and physics. Pune researchers find a spiral galaxy like the Milky Way from early universe'' (December 3, 2025)- A report on how Indian researchers discovered a massive galaxy that existed when the universe was just 1.5 billion years old , one of the earliest to have been observed so far. Signature Beat: Health, Science & Women in Leadership Anuradha is known for her COVID-19 reportage, where she was one of the first journalists to provide detailed insights into the Covishield and Covaxin trials. She has a dedicated interest in gender diversity in health and science, often profiling women researchers who are breaking the "leaky pipeline" in STEM fields. Her writing style is scrupulous, often featuring interviews with top-tier scientists and health experts from various institutions. ... Read More