As World Health Organisation funding comes under threat, Hogan Bassey offers a reminder of how coordinated efforts in the lab for critical health challenges such as malaria bring shared benefits in the field.
Malaria remains a critical global health challenge for half the world’s population, particularly in tropical regions. Despite remarkable scientific progress over the past century, the disease continues to claim approximately 600,000 lives each year, with children under five bearing the brunt of its toll.
Dr Matshidiso Moeti, World Health Organisation’s (WHO) regional director for Africa, stresses: “While Africa has shown the world what can be achieved if we stand together to end malaria as a public health threat, progress has stalled” [1]. This reflects that now more than ever there is an urgent need to reallocate resources towards eliminating malaria in African nations.
Caused by a parasite transmitted through mosquito bites, malaria begins its deadly course in the bloodstream, where the parasite multiplies and destroys red blood cells. Symptoms range from chills and severe fatigue to life-threatening complications. In severe cases, the disease can result in permanent brain damage in unborn children, underscoring its devastating impact on vulnerable populations.
A question of economy
The prevalence of malaria today is closely tied to disparities in access to health innovations. It is concerning that 58% of malaria-related deaths occur among the world’s poorest 20%, highlighting the stark inequities in global health care [2]. As reported by WHO in 2022, four African countries account for almost 50% of all malaria deaths worldwide: Nigeria (26.8%), the Democratic Republic of the Congo (12.3%), Uganda (5.1%) and Mozambique (4.2%) [3].
Malaria control relies heavily on prevention, with prompt treatment being the most crucial method to avoiding malaria-related deaths. However, when the poorest, most vulnerable in society lack access to preventative measures or quality treatment, the disease is free to spread.
New developments in the fight
Recent research breakthroughs include the development and rollout of the RTS,S vaccine, known as Mosquirix [4]. In Phase 3 clinical trials conducted between 2009 and 2014, the RTS,S vaccine reduced severe malaria cases by 22% and deaths by 13% in children aged 5-17 months [4]. With repeated booster vaccines over a four-year period, efficacy can reach up to 36% [5].
Since then, pilot programmes started in 2019 in Ghana, Kenya and Malawi, vaccinating over 1.7 million children. The WHO modelling study estimates the vaccine could prevent 5.4 million cases of malaria and 23,000 deaths annually in the vaccinated population. Global estimates of malaria cases are 249 million, which proves the vaccine is not a complete solution [6].
Mosquirix offers approximately 30% protection against malaria in children during the first year after vaccination [7], with efficacy dropping over time and requiring booster doses. However, the vaccine primarily targets Plasmodium falciparum, the deadliest malaria parasite species, offering only limited protection against other species.
Fighting malaria is like fighting several diseases at once. There are 156 species of Plasmodium, the parasite responsible for malaria, with five species infecting humans
Additionally, current prevention methods like mosquito nets and residual sprays have significant limitations.
Nets can be uncomfortable or develop holes, while sprays can harm beneficial insects and pose human health risks.
Battling a mutating foe
Fighting malaria is like fighting several diseases at once. There are 156 species of Plasmodium, the parasite responsible for malaria, with five species infecting humans. Additionally, other vector-borne diseases, such as Dengue and Zika, complicate the challenge.
Each species goes through six different lifecycles, with each phase behaving like a completely different organism, similar to the difference between a pupa and a butterfly. This is why creating a vaccine is extremely difficult and is further complicated by the speed the parasite mutates [8].
Recent observations show mosquitoes are even adapting their biting patterns, now attacking earlier in the day and reducing the effectiveness of traditional prevention methods.
However, mosquito repellents hold significant potential as part of a comprehensive toolkit to combat mosquito-borne diseases. Unlike pesticides, repellents don’t kill insects, which means they do not contribute to resistance development over time but instead deter them, which greatly reduces the risk of resistance development over time. As they do not directly eliminate susceptible individuals, they exert minimal selective pressure compared to pesticides, making resistance less likely.
Historically, mosquito repellents have shown mixed results as an effective prevention tool in community-wide vector control studies. Issues with adoption and consistent use during studies are among the reasons for these inconclusive outcomes.
I grew up in Nigeria and suffered several malaria infections by the age of 10. I saw firsthand its impacts in my community and family.
The experiences I had as a child all helped me to realise that lack of access is a systemic issue, so I co-founded LivFul to find a holistic way to solve health access.
From a strategic base on the Sci-Tech Daresbury campus, we have developed an enhanced insect repellent (EIR) using IR3535 and patented STAYTEC technology.
Extensive testing included work with the University of Ghana’s Noguchi Memorial Institute. One 16-hour study tested the effectiveness of mosquito repellents by placing volunteers’ arms into boxes containing 200 female mosquitoes. To ensure the mosquitoes were highly aggressive, the insects were starved for 24 hours prior to the experiment.
After passing the initial study, the same test was conducted with Anopheles gambiae, (described as the most efficient vector of human malaria in the Afrotropical region [9]) with no volunteers bitten or infected.
Building on its success across Africa, LivFul began gathering data in Congo and Uganda. Not only did the EIR demonstrate maintained repellency but also the test had a significant impact on the entomological inoculation rate, while also showing high efficacy against mutating mosquitoes with more than 98% fewer landings over a 16-day period. LivFul’s efforts alone are not enough to cure the malaria epidemic. A serious change in resources and effectively deploying resources would need to happen, with the right institutions showing dedication to drive that change. Malaria is curable by 2050 if the global scientific, medical community and private sectors adopt a unified, all-hands-on-deck approach to the disease. We dream about a moment like this, not only for malaria, but also for the billions who still lack access to basic healthcare.
References:
1 WHO
2 National Library
of Medicine
3 WHO
4 PATH
5 The Lancet
6 Global Citizen
7 WHO
8 PATH
9 CDC, 2010
Hogan Bassey is co-founder of LivFul, Inc
Shared genes, shared adaptations?
Chimpanzees appear genetically adapted to infections such as malaria
Chimpanzees’ genetic adaptations may protect against malaria, according to a study by an international team led by UCL researchers.
Sharing more than 98% of their DNA with humans, they offer vital clues about the biology of malaria infection in humans, say the researchers.
The Pan African Programme: The Cultured Chimpanzee enabled the largest study of local adaptation in wild endangered mammals to date, analysing exomes (the proteincoding part of the genome) from 828 wild chimpanzees. Some 388 were included in the final analysis, representing 30 different populations of chimpanzees across all four chimpanzee subspecies.
It showed evidence of genetic adaptation in genes related to certain pathogens among the forest chimpanzees, with the strongest evidence found in genes linked to malaria.This included two genes known to be responsible for adaptation and resistance to malaria in humans: GYPA and HBB, the latter being responsible for sickle cell anaemia in humans.
The findings suggest that malaria is likely a significant disease for forest chimpanzees and that adaptation to the malaria parasite happened independently in chimpanzees and humans, but through changes in the same genes.
ChimpandSee.org
