WHO approves the RTS, S/AS01 Malaria vaccine for roll-out.

Malaria is one of the leading causes of death among children under 5 years in countries where it is endemic. It has notable consequences on the health of pregnant women, infants and young children all over the globe. It is also a major cause of undernutrition in children, leading to the death of 50% of all children under the age of 5 worldwide.  Many pregnant women, over 50 million, are prone to Malaria infection every year resulting in severe maternal anaemia which has dire consequences for babies; resulting in low birth weight and related problems. Malaria also causes the death of over 800,000 children annually in Sub-Saharan Africa.2 

A Malaria infection can be either ‘Uncomplicated’ or ‘Complicated’. Uncomplicated Malaria usually presents with recurring episodes of chills, intense fever and sweating. Other symptoms include persistent headache, malaise, fatigue, body aches, nausea, and vomiting. In complicated Malaria, the disease can progress rapidly resulting in complications such as severe anaemia, respiratory distress, kidney and liver failure, cardiovascular issues, seizures, shock, coma and eventually death. Children and pregnant women are most vulnerable to this disease. Malaria thus places a substantial health and economic burden on countries where it is endemic, with a corresponding effect on the global economy.

In light of this, governments and international organizations have for years collaborated on developing a vaccine for Malaria to help mitigate the effects of this disease. Researchers have been hard at work for many decades now trying to develop a vaccine that is both high in efficacy and also cost-effective. Although it has proved difficult to develop a working vaccine over the years due to the complicated nature of the life cycle of the Plasmodium parasite, recent research has helped improve the knowledge scientists have about the parasite, how it causes the disease and how it interacts with the human immune system. 

Vaccine development and trials

Over the last decade, the completion of several genome projects related to Malaria has marked the beginning of a new generation of Malaria research. Researchers have sequenced the genomes of some Anopheles mosquito species, including the Anopheles gambiae mosquito, which is a major vector in the transmission of the disease. Scientists have also sequenced Plasmodium falciparum, the deadliest Malaria parasite, and Plasmodium vivax, the most widespread Malaria parasite. 4, 5 This has advanced the development of vaccines that have shown promise with an efficacy range of 30% to 65.9%.6

Recent breakthroughs in research has led to the development of a vaccine preparation for Malaria with up to a 50% efficacy. This is the RTS, S vaccine. It is designed to prevent the parasite from infecting the liver, thereby stopping the parasite from maturing, multiplying and causing illness. This vaccine is the result of 30 years of research and development by GlaxoSmithKline (GSK) and through a partnership with Programme for Appropriate Technology in Health (PATH), with support from a network of African research institutions. The Bill & Melinda Gates Foundation also provided catalytic funding for the late-stage development of RTS, S between 2001 and 2015.6,7 The vaccine has gone through several trial stages. The phase 3 trial stage was completed in 2014 involving over 15,000 infants across 11 sites in 7 African countries. The most recent trial phase started in 2019 covering 3 main countries; Ghana, Kenya and Malawi led by the ministries of Health of Ghana, Kenya and Malawi.6 The trials revealed that RTS, S/AS01 has the following positive profile:

  • It is practical to deliver the vaccine, and it improves the health of children and saves lives.
  • Access to the vaccine improved the prevention of the disease in children who are exposed to the risk of Malaria infection due to not sleeping under a mosquito net.
  • It has a strong safety profile because no serious side effects have been reported after having administered more than 2.3 million doses of the vaccine in the 3 African countries over the trial period.
  • The administration of the vaccine has resulted in a significant reduction (30%) in deaths related to severe Malaria. 
  • It is highly cost-effective in areas of moderate to high Malaria transmission. This is based on modelling estimates.

Roll-out of the groundbreaking RTS, S/AS01 Malaria vaccine 

On the 6th of October 2021, WHO recommended the roll-out of the remarkable vaccine across countries where Malaria is endemic and children under five years are most at risk. The recommendation is based on the positive results from the ongoing Malaria Vaccine Implementation Programme (MVIP) in Ghana, Kenya and Malawi that has reached more than 800 000 children since 2019. The vaccine is recommended for children in Sub-Saharan Africa and in other regions with moderate to high Plasmodium falciparum Malaria transmission as it has proven effective against this parasite, which is the most deadly Malaria parasite globally, and the most prevalent in Africa.2

In the statement, WHO Director-General Dr. Tedros Adhanom Ghebreyesus said, “This is a historic moment. The long-awaited Malaria vaccine for children is a breakthrough for science, child health and Malaria control.”

WHO intimated that the MVIP in the 3 pilot countries had generated evidence and experience on the feasibility, impact and safety of the RTS, S/AS01 Malaria vaccine in real-life and routine settings.2

The recommendation of the vaccine by WHO paves the way for an extensive roll-out across the three selected countries and also in others with a high prevalence of the disease. The organisation states that the MVIP will continue in the 3 pilot countries to further understand the long-term impact. 

The MVIP is coordinated by WHO and supported by in-country and international partners, including PATH, GSK and UNICEF. GSK is donating up to 10 million doses of the vaccine for the roll-out.

In an interview conducted on the 21st of April 2021, Dr. Keziah Malm the Programme Manager for the National Malaria Control Programme in Ghana said, “Ghana is one of 11 countries with the highest burden of Malaria in the Sub-Saharan region of the African continent.” She also stated that Malaria is still the number one cause of out-patient hospital visits in the country and is hopeful that the uptake of the Malaria vaccine will continue to rise so that the country can continue to reduce the Malaria burden.3

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February 4, 2022