The world has made progress toward eliminating malaria, with 44 countries and one territory (La Réunion) certified as malaria-free. Egypt, where malaria has existed since at least the time of the pharaohs, joined the malaria-free list in October.
Between 2000 and 2023, an estimated 2.2 billion cases of malaria and 12.7 million deaths from the mosquito-borne disease were averted, according to a report from the World Health Organization issued December 11.
But challenges including climate change, conflict and biological threats have eroded some recent gains, with 11 million more malaria cases in 2023 than in 2022. Most of those cases occurred in Africa. Globally 597,000 people died of malaria in 2023, the majority of them young children in Africa. That’s down slightly from 600,000 worldwide in 2022.
WHO has called for a 75 percent reduction in deaths from malaria by 2025 compared with 2015 levels. That would be 5.5 deaths among 100,000 people at risk for the parasitic disease. But in 2023, the death rate was more than double that target at 13.7 deaths per 100,000 at-risk people. And the incidence of malaria cases worldwide is nearly three times higher than the goal.
Malaria is an ancient disease, says Jane Carlton, a geneticist and director of the Johns Hopkins Malaria Research Institute. “It’s been around for very long time and that’s because it’s so challenging to try and get rid of.”
Here’s a closer look at the challenges and the successes in the fight to eradicate malaria.
What are the biggest challenges to eliminating malaria?
Evolution is one of the biggest threats to malaria-control efforts, Carlton says.
“The malaria parasite is a very crafty biological species. It can evolve very fast,” Carlton says. It has become resistant to nearly every drug deployed against it.
Now, that includes partial resistance to artemisinin, a drug used to treat the disease. Partial resistance to the drug has been confirmed in Eritrea, Rwanda, Uganda and Tanzania, while the WHO suspects partial resistance may be present in Ethiopia, Namibia, Sudan and Zambia.
“That’s very concerning,” says William Moss, a pediatric infectious diseases expert at the Johns Hopkins Malaria Research Institute. “If we lose those drugs, that’s going to be a major setback.”
Malaria parasites have also lost part of a gene that is the basis of a rapid test used to diagnose the disease (SN: 4/25/24). Parasites with the missing bit of the gene were reported in 41 countries where malaria is endemic, the WHO report says.
In Southeast Asia, a malaria parasite called Plasmodium knowlesi that primarily infected monkeys is increasingly infecting people (SN:11/4/18). In 2023, 3,290 cases were reported, up from 2,768 cases reported in 2022.
Mosquitoes are also evolving resistance to insecticides and spreading to places they’ve never been seen before. Between 2018 and 2023, 55 countries recorded mosquitoes resistant to pyrethroid insecticides used in bed nets. And five countries have reported mosquitoes resistant to neonicotinoid insecticides.
In addition, a species of malaria-carrying mosquito called Anopheles stephensi has been invading Africa (SN: 11/2/22). That species is native to South Asia but has now been found in eight African countries. It’s a concern because it lives and breeds easily in urban areas, Moss says. That could mean greater transmission in cities.
Climate change and severe weather are also threats. For instance, flooding in Pakistan in 2022 skyrocketed malaria cases from 506,000 in 2021 to 4.3 million in 2022. One analysis forecasts that climate change could cause 550,000 more malaria deaths globally between 2030 and 2049.
Human factors also threaten progress. Political unrest, armed conflict, economic turmoil and unstable health care systems make it hard to deliver malaria prevention and treatment. “In those countries where the health system has been improving over the years, which are stable economies, they have the potential, the possibility of being able to eliminate malaria,” Carlton says. “In other countries where the health systems are not very well developed, where they may be war-torn [or] countries where there’s political strife, [those are] countries where malaria is still going to hold out unfortunately.”
What are the most promising strategies to get rid of malaria?
New malaria vaccines may decrease the toll malaria takes on young children (SN: 6/30/21), Moss and Carlton say. The vaccines are only beginning to be deployed so they have not yet made a big dent in malaria deaths, Moss says.
But from 2019 through 2023, about 2 million children in Ghana, Kenya and Malawi got the first approved malaria vaccine known as RTS,S/AS01. The vaccine was linked with a 13 percent reduction in death from all causes except injury, and a 22 percent reduction of hospitalizations for severe malaria. As of December 2024, 17 countries have introduced malaria vaccines as part of routine childhood vaccinations.
Carlton is also excited about genetically modified mosquitoes that may reduce or even crash mosquito populations or make the mosquitoes unable to carry the malaria parasites (SN: 6/3/22). Such “gene-drive” carrying mosquitoes have not been released in the wild and are probably years away from deployment if they are ever approved by countries where they might be used. The genetic manipulation causes a particular gene — such as one that causes sterility or immunity against the malaria parasite — to be inherited by a majority of offspring. Some people worry that it could drive species of mosquitoes extinct or have unknown ecological consequences. Several African countries are considering allowing release of such genetically modified mosquitoes, Carlton says. “It’s still a bit of an uphill route, I would say, but I can see light at the end of the tunnel.”
Improved bed nets that use combinations of insecticides are increasingly being deployed, according to the WHO report. Such combinations may combat insect resistance.
More young children are being given seasonal malaria prevention treatments. In 2023, an average of 53 million children were treated per cycle, up from 170,000 in 2012. Nigeria alone treated 28.6 million children last year. Ivory Coast and Madagascar are the latest countries to deploy the treatments, bringing the tally to 19 African countries.
People in 34 African countries are being given malaria prevention treatments during pregnancy. In 2023, 44 percent of eligible pregnant women and girls got the full three-dose treatment — still far below the target of 80 percent.
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