Its not too late to say that 2021 is a year of vaccines. From numerous vaccines for CoViD, a viral disease that has killed more than 4.8 million people worldwide to a vaccine for Malaria, we actually have come a long way.
A vaccine for Malaria is undoubtedly a historic moment and one of Medicine’s biggest achievements.
It has been 130 years since the day when Plasmodium parasites were named behind the malaria and now the world has a vaccine approved against them. On October 6th, WHO approved the vaccine called “RTS,S” and recommended its widespread use among children in sub-Saharan Africa. If you are not aware, sub-Saharan Africa is home to the deadliest malaria parasite, Plasmodium falciparum.
Though the malaria vaccine brings hope, it’s not wrong to say that the fight is still far from over.
The Deadly Malaria
Malaria is one of the deadliest and oldest known infectious diseases transmitted by the anopheles mosquito. It is caused by Plasmodium parasite that has a multistage lifecycle and results in characteristic cyclical fevers. Rapid resolution of symptoms is seen in most cases with timely treatment. However, this disease being so life threatening is associated with significant complications that include cerebral malaria, severe malarial anemia, coma, or death.
What causes it?
There are five plasmodium species that have the ability to infect humans. These include P. falciparum, P. ovale, P. vivax, P. malariae, and P. knowlesi. 
Statistics worth knowing
Forty percent of the total global population resides in or visits malaria-endemic regions annually. P. falciparum is present in Western and sub-Saharan Africa and displays the highest morbidity and mortality of the Plasmodium species. P. vivax is present in South Asia, the Western Pacific, and Central America. P. ovale and P. malariae are present in Sub-Saharan Africa. P. knowlesi is present in Southeast Asia.
As many as 500 million cases of malaria occur annually, with 1.5 to 2.7 million deaths. Ninety percent of fatalities occur in Africa. Those at highest risk include children under age 5, pregnant women, and disease naïve populations, including refugee populations in Central and Eastern Africa, nonimmune civilian and military travelers, and immigrants returning to their place of origin. 
New RTS,S malaria vaccine
RTS,S/AS01 (RTS,S) is a vaccine that acts against Plasmodium falciparum, the deadliest malaria parasite globally and the most prevalent in Africa. In January 2016, the vaccine was recommended by WHO for pilot introduction in selected areas of 3 African countries. RTS,S is being evaluated for use as a complementary malaria control tool that could be added to (and not replace) the core package of WHO-recommended preventive, diagnostic and treatment measures. 
It’s very important to note that the vaccine offers no protection against P. vivax malaria, which predominates in many countries outside of Africa.
Let’s talk about its efficacy
A Phase 3 trial was conducted over 5 years (2009-2014) enrolling approximately 15 000 young children and infants in 7 sub-Saharan African countries.
Among children aged 5–17 months who received 4 doses of RTS,S, the vaccine prevented approximately 4 in 10 (39%) cases of malaria over 4 years of follow-up and about 3 in 10 (29%) cases of severe malaria, with significant reductions also seen in overall hospital admissions as well as in admissions due to malaria or severe anaemia. The vaccine also reduced the need for blood transfusions, which are required to treat life-threatening malaria anaemia by 29%. 
Known side effects of the vaccine
Known side effects include pain and swelling at the injection site, and fever. These side effects are similar to reactions observed with other vaccines given to children. The vaccine is associated with an increased risk of febrile seizures within 7 days of the administration. In the Phase 3 trial, children who had febrile seizures after vaccination recovered completely and there were no long-lasting consequences. 
What’s the challenge?
Malaria isn’t just a disease of high grade fever. It may lead to damage of different organs especially when the infecting parasite is plasmodium falciparum. It can lead to anemia, jaundice, liver and kidney dysfunctions, diarrhea and many other serious illnesses.
What makes it more important is its unique ability to silently destroy an entire generation. This is because there could be many asymptomatic cases in which the parasite continues to destroy the red cells and ultimately affects the cognition, nutrition and work capacity.
- Buck E, Finnigan NA. Malaria. [Updated 2021 Aug 11]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK551711/