A few days after a mosquito bites and infects you with the malaria parasite, you will feel as if you have flu.
You will also experience abrupt chills that transition to profuse sweating, high fever and headaches.
If untreated, the parasite could eventually destroy the red blood cells, leading to failure of organs such as the kidneys. Death follows quickly.
In 2023, about 10,000 Kenyans, mostly young children, went through this cycle and died – according to estimates by the Ministry of Health.
This makes malaria one of the deadliest diseases in Kenya.
But tests partly conducted in Kenya show one vaccine is extremely effective in helping the body fight the malaria parasite, just before you feel the flu symptoms.
The vaccine, known as R21/Matrix-M, has a high efficacy level of about 75 per cent, compared to 30 per cent of RTSS, the only other malaria vaccine available.
R21 is now expected to be more widely available in Kenya in 2024, this is after the World Health Organisation awarded it prequalification status late last month.
This coveted status means the vaccine is safe, effective and of good quality.
Currently, it is only available to children taking part in clinical tests in Kilifi.
“Now with two prequalified malaria vaccines, children in at-risk settings, predominantly in Africa, can receive even more protection through safe and effective vaccines,” WHO chief Dr Tedros Adhanom said on his X (formerly Twitter) account.
The decision was based on pre-clinical and clinical trial data which showed good safety and high efficacy in four countries, at sites with both seasonal and perennial malaria transmission.
About 600 Kenyan children have been participating in phase three trials for R21 vaccine conducted in Kilifi by Kemri-Wellcome Trust.
“The vaccine was well tolerated with injection site pain and fever as the most frequent local and systemic adverse events,” the researchers said in a report of the Phase III trial, published by the Lancet.
A total of 4,800 children across Burkina Faso, Kenya, Mali and Tanzania took part in the trial.
Ghana became the first country to approve its rollout on April 13, 2023.
The vaccine was developed by the University of Oxford Jenner Institute in partnership with the Serum Institute of India, and was partly tested in Kenya in collaboration with the Kemri Wellcome Trust.
Prof Sir Adrian Hill, director of The Jenner Institute, said in a statement: “The disease presents a uniquely difficult scientific challenge: the complex composition of malaria parasites with shape-shifting pathogen that has learned how to evade our immune system, has made the development of an effective vaccine a formidable task. R21/Matrix-M represents the culmination of 30 years of collaborative research and development.”
The vaccine targets the plasmodium 'sporozoite', which is the first form of the malaria parasite entering the human body.
Adar Poonawalla, CEO of the Serum Institute of India, said; “We stand ready to produce up 100 million doses for the first year, which will be scaled up to 200 million doses (per annum) over the next two years.”
The Phase III trial results showed high efficacy when the vaccine was given just before the high transmission season.
In areas with highly seasonal malaria transmission (where malaria transmission is largely limited to four or five months per year, it reduced symptomatic cases of malaria by 75 per cent during the 12 months following a three-dose series.
In comparison, four doses of RTS,S vaccine reduce clinical malaria cases by 39 per cent and severe malaria by 30 per cent.
RTSS is already widely available in Western Kenya.
According to Gavi, the vaccines financier based in Geneva, both vaccines will not end Malaria.
However, when used with other preventive tools, like bed nets and seasonal chemoprevention, they will prevent many deaths and sicknesses.
In a new paper, Gavi outlined how the world can increase supply to meet demand by growing the number of manufacturers and supporting scale-up through predictable demand.
Dr Seth Berkley, CEO of Gavi, said; “It has taken the world more than 50 years to develop a malaria vaccine. Yet this year’s launch serves only as a reminder of what needs to happen now if we are to make malaria vaccines accessible to every child that needs them.”
With an estimated 40-60 million doses currently to be needed by 2026 alone, growing to 80-100 million doses of vaccines needed each year by 2030, Gavi said governments, vaccine manufacturers and health agencies must take action to meet this goal.
Malaria remains one of Africa’s biggest killers and is estimated to cause 10,000 deaths in Kenya every year.
The major impediment that now stands in the way of a widespread rollout of malaria vaccines in endemic countries is supply, Gavi said.
Gavi’s outline requires countries and partners to work together in key areas such as demand forecasting, boosting the number of suppliers and technology transfer.
“We know how long African countries have waited for a vaccine against one of its greatest killers: if global health, countries, suppliers and civil society come together, we can soon contribute to preventing tens of thousands of child deaths every year along with other malaria control interventions," Dr Berkley said.