Malaria is a life-threatening infection which is transmitted by mosquitoes. It’s currently present in 84 countries. Annually, a quarter of a billion cases occur, killing over half a million people.  Most cases, and most deaths, occur in sub-Saharan Africa.  Most deaths in sub-Saharan Africa occur in children under the age of five years.

Malaria is not rare in international travelers. Every year, about 2,000 travelers from the U.S. acquire malaria while traveling abroad. In 2023 there were over 2,000 cases of malaria in travelers from the U.K.

Taking a preventative medication is highly effective in reducing risk.  Analysis of cases of malaria in the U.S. reveals that almost all travelers who become infected either took no medication to prevent malaria, or an incorrect medication.

To determine whether or not you need to take a medication for malaria in a given country, check out the CDC (U.S. Centers for Disease Control and Prevention) site Yellow Fever and Malaria Prevention Information, By Country. This site lists, for every country in the world, whether or not malaria is transmitted. Additionally, it lists where in each country malaria is transmitted, and which medications are and are not effective.

For example, for Tanzania, it states that malaria is transmitted in all areas below 5,900 feet (1,800 meters).  The malaria there is resistant to chloroquine.  Effective medications are atovaquone-proguanil (Malarone), doxycycline, mefloquine, and tafenoquine.

In addition to taking a preventative medication, using usual insect precautions (applying an effective insect repellent, such as DEET or picaridin, to exposed skin; applying permethrin to clothing, and sleeping under a mosquito net) offers significant additional protection.

References

CDC Yellow book 2024: Yellow Fever and Malaria Prevention Information, By Country

CDC Yellow Book 2024: Malaria

Sanford C, Pottinger P, Jong EC (eds.):  The Travel and Tropical Medicine Manual, 5th Edition. Elsevier.  September, 2016.

Sanford C. Staying Healthy Abroad: A Global Traveler’s Guide.  University of Washington Press.  December 2018.