Malaria is most common in sub-Saharan Africa, which accounts for roughly 95% of all malaria deaths worldwide. In 2023, there were an estimated 263 million cases and 597,000 deaths globally, with the vast majority concentrated in tropical and subtropical regions where the mosquitoes that spread the disease thrive year-round.
Sub-Saharan Africa Carries the Heaviest Burden
Africa’s malaria crisis dwarfs every other region. The combination of warm temperatures, seasonal rainfall, and limited access to prevention and treatment makes sub-Saharan Africa the global epicenter of the disease. The type of malaria parasite that dominates here, known for causing the most severe and fatal infections, thrives in conditions found across much of the continent. Countries in West and Central Africa, the Sahel, and East Africa all report significant transmission, though the timing varies by region.
In the Sahel, which stretches across the southern edge of the Sahara, malaria is intensely seasonal. The single rainy season runs roughly June through October, and malaria transmission peaks about one month after the rains begin. During the long dry season from November through May, mosquitoes are largely absent. In contrast, West and Central African coastal regions see transmission year-round with no gap between the start of rains and the start of malaria season. East Africa follows a pattern similar to the Sahel, with transmission peaking about a month after rainfall peaks.
South and Southeast Asia
Outside of Africa, South and Southeast Asia carry the next largest share of global malaria cases. The dominant parasite species here is different from Africa’s. This form of malaria is less immediately deadly but harder to eliminate because it can lie dormant in the liver and cause relapses months or even years after the initial infection. Southeast Asia’s Greater Mekong subregion, covering parts of Cambodia, Laos, Myanmar, Thailand, and Vietnam, has been a particular concern not just for case numbers but because parasites there were among the first to develop partial resistance to the most important class of antimalarial drugs.
India alone contributes a large proportion of cases in the region, and both major parasite species circulate there. Densely populated areas in South Asia put billions of people within range of transmission, even if rates per person are lower than in Africa.
The Amazon Basin and the Americas
In the Western Hemisphere, the Amazon rainforest is where malaria concentrates. Brazil, Colombia, Peru, and Venezuela all have endemic transmission in their Amazonian regions, and more than half of South American malaria cases are caused by the relapsing form of the parasite rather than the more lethal African variety. Gold mining operations, migrant labor, and other mobile populations working deep in forested areas face especially high infection risk. Urban malaria cases have also been reported in Brazilian, Colombian, and Venezuelan cities, though overall the disease remains far more common in remote, forested areas.
Central America has seen major progress. Belize was certified malaria-free by the WHO in 2023, and El Salvador received the same certification in 2021. These successes show that elimination is possible in lower-transmission settings with sustained investment.
Altitude and Temperature Shape Risk
Malaria transmission depends heavily on temperature. The parasites need 8 to 14 days to develop inside a mosquito, and that process only happens efficiently when average temperatures sit between about 20°C and 25°C (68°F to 77°F). If temperatures drop too low, the parasite can’t mature before the mosquito dies. This is why altitude matters so much in tropical countries. Research in the Himalayas found that malaria transmission was possible at low and mid-elevation sites (up to about 2,000 meters, or 6,500 feet) during warm months, but at 3,200 meters (10,500 feet) temperatures were too cold for transmission at any time of year.
This pattern holds across Africa and Latin America as well. Highland cities like Addis Ababa or Nairobi sit at elevations where malaria risk is much lower than in surrounding lowlands, though rising temperatures are pushing transmission into some highland areas that were previously too cool.
Rural Areas vs. Cities
Malaria has long been considered a rural disease, and for good reason. Rural areas with standing water, agricultural irrigation, and proximity to mosquito breeding sites consistently report higher infection rates than nearby urban centers. Studies across multiple countries have documented this gradient: as you move from city centers toward more rural, agricultural surroundings, mosquito populations increase and so does infection prevalence.
That said, malaria is not absent from cities. Urban transmission has been documented at surprisingly high rates in some African and South American cities, particularly in neighborhoods near irrigation, vegetable farming, or other water sources that support mosquito breeding. The assumption that city living protects you from malaria doesn’t always hold.
Drug Resistance Hotspots
The Greater Mekong subregion in Southeast Asia was the first place where parasites developed partial resistance to artemisinin, the backbone of modern malaria treatment. That resistance likely emerged before 2001 and has since appeared independently at multiple locations within the region. More alarming, artemisinin partial resistance has now been confirmed in four African countries: Eritrea, Rwanda, Uganda, and Tanzania. These resistant parasites emerged on their own rather than spreading from Asia. Resistance is also suspected in Ethiopia, Namibia, Sudan, and Zambia.
This matters because Africa is where the overwhelming majority of malaria deaths occur. If frontline treatments lose their effectiveness there, the consequences would be severe.
Countries Recently Certified Malaria-Free
On the other end of the spectrum, several countries have recently eliminated malaria entirely. The WHO certified China and El Salvador as malaria-free in 2021, Azerbaijan, Belize, and Tajikistan in 2023, and Cabo Verde and Egypt in 2024. These certifications require proof that local transmission has been interrupted for at least three consecutive years, with a surveillance system capable of catching and responding to any reintroduction.
Since 2000, global efforts have averted an estimated 2.2 billion malaria cases and 12.7 million deaths. But with 263 million cases still occurring annually, the disease remains deeply entrenched in tropical Africa, parts of Asia, and pockets of the Americas where warm temperatures, adequate rainfall, and limited healthcare access create ideal conditions for transmission.