Malaria prevalence Prevalence on the mainland varies by region from <1 percent in the highlands of Arusha to as high as 15 percent in the Southern Zone and 24 percent along the Lake and Western zones.

Malaria is prevalent in almost all areas of Tanzania below an elevation of 1,800 meters (5,900 feet). The risk is highest in the low-lying coastal regions, including Dar es Salaam, and the areas surrounding Lake Victoria and Lake Nyasa. Even in popular safari destinations like the Serengeti and Ngorongoro Crater, the risk remains present, though it is slightly lower due to the higher altitude and cooler nighttime temperatures. The only areas considered "low risk" or nearly malaria-free are the high-altitude peaks of Mount Kilimanjaro and Mount Meru. It is important to note that the Zanzibar Archipelago also has a risk of malaria, despite successful eradication efforts in the past. Because the Anopheles mosquito is most active at night, travelers are strongly advised to take prophylaxis (preventative medication), use DEET-based repellents, and sleep under insecticide-treated mosquito nets. Even during the dry season, the risk persists, making medical consultation before your trip an essential safety step.