By Sharon Atieno
Though a sunny morning in Nyawiso village, Ndhiwa sub-county, the bushy path leading to 38-year-old Judith Atieno’s home is partly wet.
It had rained the previous night, so the green grass was moist, and water puddles were visible where there was bare soil, which is suitable for breeding malaria-causing mosquitoes.
Ndhiwa sub-county is one of the eight sub-counties in Homa Bay County. The County is classified under the Lake endemic regions, where malaria poses a critical challenge with a prevalence rate of 19%.
I find Judith and her two young children, aged three and one, seated by the door of her tin-roofed mud-thatched house having breakfast– tea, and mandazi. She quickly stands up to greet me and the community health promoter (CHP) who has accompanied me to her home.
She then grabs a backless wooden bench that she wipes with the edge of her skirt. Without much preparation, she sits on the green grass of her verandah, not caring about the dew. Her three-year-old son tightly clings to her blouse while the one-year-old girl remains at the door playing with her tea.
Eight years ago, her firstborn child was struck down by severe malaria. At the time, the boy was only five years old. The disease had only infected him for a few days, but he had become so weak that he could barely walk, Judith recounted.
“The malaria was so serious that when we rushed him to the hospital for treatment, on arrival, he was hit with diarrhea so bad that he ended up relieving himself on the doctor,” recalls the mother of five, laughing. “We thought he was going to die.”
From diarrhea, high fever, lack of appetite, headache, and other symptoms, the doctor pre-diagnosed malaria but ordered a blood test to confirm this. The test came back positive.
Atieno and her husband were relieved when, after getting the medication and adhering to the instructions, the boy got better in a few days.
The boy and his other two siblings have contracted malaria many times as infants, but the memory of that day still lingers on in Atieno’s mind.
photo credits: Sharon Atieno
Malaria remains a significant health burden in Kenya, with more than seven out of ten people being at risk of infection, including vulnerable groups such as pregnant women and children, according to the 2020 Kenya Malaria Indicator Survey.
The disease is the second-leading cause of hospital outpatient visits, accounting for the national disease burden.
Further, the Centers for Disease Control and Prevention (CDC) approximates that malaria kills about 10,000 Kenyans annually, mostly young children.
Besides Kenya, the entire World Health Organization (WHO) Africa region carries a disproportionate majority of the global malaria burden, with children being among the most affected.
In 2022 alone, there were 249 million cases and 608,000 deaths globally. The continent accounted for 94% of all cases and 95% of deaths. Children under five years of age accounted for about 78% of malaria deaths in the region.
However, introducing the malaria vaccine in the fight against the disease in 2019 has relieved mothers like Atieno. She notes that, unlike her first three children, she no longer has to constantly go to the hospital to seek malaria treatment for her two young ones.
“Malaria is now a disease of the past…My first three children used to be constantly sick. But now, these others no longer get as sick, and we don’t constantly go to the doctor. That is the good thing about this vaccine,” she says.
Her three-year-old son has finished the four doses, administered at six, seven, nine, and twenty-four months. She is now waiting for her one-year-old daughter to turn two so that she can take her for the last dose of the vaccine.
The vaccine
photo credits: WHO Malawi
RTS,S/AS01 (RTS,S), developed by GlaxoSmithKline (GSK), is the world’s first malaria vaccine to be approved to combat a human parasitic disease. It acts against Plasmodium falciparum, the deadliest malaria parasite globally and the most prevalent in Africa.
Other malaria parasites include P. vivax (the dominant malaria parasite in most countries outside of sub-Saharan Africa), P. malariae, P. ovale and P. knowlesi, as they are known by their scientific names.
The vaccine took more than 30 years to develop, and it was funded by the Bill and Melinda Gates Foundation and PATH.
Clinical trials conducted between 2009 and 2014 through a network of African research sites, including three sites in Kenya (Kombewa, Siaya, and Kilifi) involving more than 4,000 Kenyan children, found that the vaccine reduced clinical malaria cases by 36.3%.
The roll-out
The RTS,S Malaria vaccine was introduced in Kenya in 2019 under a WHO-coordinated pilot program, which also covered Malawi and Ghana. The Ministry of Health implemented the pilot program in the eight high malaria transmission counties of Homa Bay, Kisumu, Migori, Siaya, Busia, Bungoma, Vihiga, and Kakamega.
In Homa Bay County, Dr. Gordon Okomo, County Health Director, notes that the pilot began with three sub-counties: Ndhiwa, Rachuonyo East, and Rangwe. Part of the pilot was surveillance to check mortality and adverse effects caused by the vaccine.
The results showed that while mortality among vaccinated children was reduced by 13%, hospitalizations from severe forms of malaria declined by 22%.
Additional funding from Gavi, the Vaccine Alliance, facilitated increased vaccine access to the pilot countries. Through this, Kenya increased the number of sub-counties benefitting from the vaccine within the Lake endemic region from 26 to 51.
Photo credits: Sharon Atieno
Dr. Okomo says there has been a positive vaccine uptake because of the number of interventions. These include dialogue and public participation with community members about the vaccine and its benefits, behavior change, and communication campaigns to ensure the public’s positive reception.
He notes that the participation and involvement of the community during the vaccine launch made acceptance easy. “The launch being done in Homa Bay gave us mileage because the whole world was here,” Dr. Okomo states, adding that residents felt privileged.
The healthcare workers were also trained in vaccine administration and storage. The County also had to put in place proper storage capacity for the vaccines, which is currently at 98%. This ensures that there are no missed opportunities and that walk-ins and outreaches are adequately handled.
Additionally, they leverage the Community Health Promoters (CHPs) to map out children and conduct follow-ups with the mothers.
As a result of the vaccine roll-out, Dr. Okomo notes: “We are seeing close to 34% reduction of hospitalizations due to malaria. The prevalence has also reduced from 27% in 2015 to 3.6%. Malaria was the leading cause of death for under-5s, but we have seen a reduction of close to 40%.”
Results from the implementation pilot of the RTS, S vaccine show that it reduced deaths from all causes by 13% in children in the age group eligible for vaccination. The vaccine was also responsible for a 22% decrease in hospitalization for severe clinical malaria in the same group.
To understand more about the malaria rollout in Homa Bay County, I visited the Ndhiwa sub-county hospital, where the pilot program was launched in 2019.
With services like maternity, laboratory, and special clinics dealing with various ailments, including diabetes, hypertension, and sickle cell disease, the level four hospital serves a population of about 24,228 people annually, with spillovers coming from outside its target area.
According to Hellen Agoro, Deputy Nursing Officer-in-charge, malaria-related complications and deaths have declined since the vaccine was rolled out in the county.
She says that one of their main strategies is conducting health talks when women come to the hospital. The talks begin during the administration of the first vaccine—the Bacillus Calmete-Guerin (BCG) vaccine for TB—and the oral polio vaccine (OPV), done after delivery and during birth. They inform the women on which immunizations to expect, including the malaria vaccine, which begins at six months.
Nurse Agoro observes that the CHPs have been instrumental in promoting the uptake of vaccines at the community level. This is because CHPs work closely with the Ministry of Health to spread promotional health messages, including on vaccination.
Photo credits: Sharon Atieno
Beatrice Aoko is one of the CHPs in Nyawiso village. She is in charge of 114 households. Part of her work is conducting door-to-door visits and providing essential health services, such as health education, disease prevention, and treatment.
Regularly, she moves from one household to another, checking on pregnant women and children under five years, defaulter-tracing HIV clients, and conducting malaria and pregnancy tests before making referrals to the hospital for further assistance. She also gives family planning education.
Aoko notes that when the vaccine was first introduced, some hesitancy was observed because mothers did not understand it. “But the more we sensitized them about the vaccine is when they realized its importance,” she says.
“When the women started adhering to our advice to get the vaccine and could witness the reduced cases of malaria for themselves, the CHPs no longer had to remind them as they took themselves to the hospitals,” narrates Aoko.
Even so, with every household visit, they still have to check the mother-child booklets to see when the babies are due for their next vaccine and remind their mothers not to fail to take them to the clinic for the four doses.
Additionally, the CHPs encourage the mothers to ensure that their children sleep under treated mosquito nets and remind them to keep their environment clean by draining away stagnant water and clearing bushes that provide mosquito breeding grounds, Aoko reiterates.
Photo credits: Sharon Atieno
A few metres from Atieno’s home, we find Milkah Auma, a mother of four children. Her youngest kids are one year and three months and three years and two months old. Both are beneficiaries of the malaria vaccine.
The eldest of the two young children is playing around the compound while their mother is busy sweeping. On seeing us, she stops sweeping and welcomes us to her neatly arranged abode- a tin-roofed house whose walls are traditionally plastered with soil and cow dung mixture.
Similar to Atieno, she has had a fair share of malaria affecting her two older children. “Looking at then and now, vaccination is good. Previously, malaria was ever present among children, they would suffer from fever and vomiting which didn’t stop. I would be in the hospital constantly,” narrates Auma.
“You would go somewhere and when you come back, you find the child is sick. The body is hot and feverish. When you give them something to eat, they keep vomiting. My two elderly children kept disturbing me with sickness, but malaria has not been a source of suffering for these two young ones. Besides taking them for vaccination, I have not taken them to the hospital because of any sickness.”
Already, her lastborn child has received the malaria vaccine administered at nine months, and she is waiting to take him for the last dose given at twenty-four months.
“I have seen the goodness of this vaccine… I urge all mothers to vaccinate their children because it helps prevent so much,” she opines.
Since 2019, the WHO Kenya country office estimates that the country has administered more than 1.8 million vaccine doses, with 650,000 children receiving at least one dose.
Aided by Gavi, other African countries now include the malaria vaccine in their routine childhood immunization schedule. Cameroon became the first country outside the pilot countries to do so in January 2024.
Cameroon is one of the countries where malaria cases have been rising since 2017. Nearly 30% of all hospital visitations in the country are malaria-related.
The vaccine rollout is covering 42 districts in the country’s 10 regions. By the end of 2024, the country will receive 662,000 doses of the vaccine.
“Across the African continent, we have 20 countries that have planned to introduce malaria vaccines in routine immunization programs. Some have already received certain doses and are making preparations for launch. Overall, we have more than 30 African countries today who have expressed interest in the malaria vaccination program,” Aurélia Nguyen, Chief Programme Officer, Gavi said during a press briefing before the Cameroon roll–out.
Already, Burkina Faso, Liberia, Niger, and Sierra Leone have received 1.7 million doses of the vaccine for their routine national rollout programs.
Despite the demand, Gavi says only 18 million vaccine doses are available for allocation before 2025.
However, in December 2023, WHO recommended another malaria vaccine, R21/ Matrix-M (R21), developed by Oxford University. Pending regulatory approvals, the Serum Institute of India will manufacture 100 million doses of this drug per year, thus increasing dosage availability to tackle malaria.
Like RTS, S vaccine, the second malaria vaccine is safe and highly effective. Clinical trials showed a 66% efficacy during the 12 months following the first three doses, with the fourth dose maintaining efficacy.
Besides the two approved vaccines, there are 65 others in different research and development (R&D) stages as of August 2023. WHO estimates that over the past 20 years, new malaria trials have been registered at a rate of 10 trials per year.
The global health body’s preferred product characteristic (PPC) document for malaria vaccines outlines three strategic goals: malaria vaccines that prevent human-blood stage infection at the individual level, malaria vaccines that reduce morbidity and mortality in individuals at risk in malaria-endemic areas, and malaria vaccines that reduce transmission of the parasite and thereby substantially reduce the incidence of human infection in the community.
However, most of the vaccines in the R&D pipeline are pre-erythrocytic vaccines (target antigens developed from parasite injection by mosquitoes into the skin) that partially prevent blood-stage infection and blood-stage vaccines that decrease parasite density. Though these vaccines help reduce the burden of malaria disease and death (strategic goal 2), they would have less effect on transmission (strategic goal 3).
The organization notes that highly efficacious long-duration vaccines against blood-stage infection (strategic goal 1) would help reduce malaria burden and eliminate malaria. They would not only prevent individual-level infection, thereby reducing disease and death (strategic goal 2) but could also reduce community-level transmission (strategic goal 3) if given to a substantial proportion of the population that infects mosquitoes with malaria.
Before then, WHO stresses that the approved vaccines must be combined with other interventions, such as routine use of insecticide-treated bed nets, indoor insecticide spraying, and timely access to malaria testing and treatment.
“We won’t see the progress that we are hoping to get through the vaccine if we are trading off other prevention for the vaccine. Moreover, the highest impact is seen when malaria prevention tools are used together,” Kate O’Brien, Director of WHO’s Department of Immunization, Vaccines and Biologicals, said during the Cameroon vaccine roll-out.
“No one intervention for malaria is going to be that one thing that a family needs to do. It is about adding all of them together.”
Despite the vaccine’s success in Kenya, one major challenge remains the uptake of the fourth dose.
“The main challenge is low uptake of the fourth dose taken at the 24th month. Because at this time these kids are two years and we don’t do monthly monitoring of these kids when they go beyond one year. Even if you look at the other antigen compared to this, the second dose of the Measles vaccine, we have the same challenge. But we are working around it with the CHPs at our community units to mobilize these kids so that they can get to us,” Agoro says.
Similarly, Dr. Okomo notes: “Since there is a long break after the nine months’ vaccines, parents tend to forget to bring their children back for the 24 months vaccine, posing a challenge not only for malaria but also the last measles vaccine.”
Perhaps the health authorities should extend the CHPs’ child-monitoring period from one to two years to ensure all children complete their malaria and measles vaccine doses.
This story was first published in Science Africa
