São Tomé and Príncipe was close to ending malaria. Then cases tripled.
- Travel clinic CDC recommends medicine or vaccines for some areas · which ones
- No CDC travel notice for mosquito-borne disease
WHO had counted the islands among the countries that could eliminate malaria in 2025, until 7,118 confirmed cases in 2024 ruled that out. CDC recommends prevention medicine for both islands, Príncipe included, and the day-biting mosquitoes behind the 2022–24 dengue outbreak are established on both, so the routine runs from morning to night.
Are there mosquitoes in São Tomé and Príncipe? Yes, and CDC recommends prescription medicine to prevent malaria on both islands. Malaria had fallen close to elimination before confirmed cases tripled in 2024, and dengue caused the country's first reported outbreak in 2022, so a family visit, an aid posting or a lodge stay starts at a travel clinic.
Malaria came back in 2024
Confirmed cases stayed between about 2,000 and 4,000 a year from 2020 to 2023, with 2,368 in 2023, then jumped to 7,118 in 2024, according to WHO's World Malaria Report 2025. WHO had counted São Tomé and Príncipe among the countries that could eliminate malaria in 2025. In June 2025 it said the recent rise in cases ruled that out, and the national goal is now zero locally acquired cases by 2027. Deaths have stayed near zero, with one estimated in 2024.
What CDC says: "CDC recommends that travelers going to São Tomé and Príncipe take prescription medicine to prevent malaria." It lists the transmission areas as "All," Príncipe included, and names atovaquone-proguanil, doxycycline, mefloquine and tafenoquine as the options. What we suggest you do with this: book a travel-medicine appointment 4–6 weeks before departure and bring your dates and every place you'll sleep on both islands. Our malaria-zone checklist covers everything around the prescription.
Travelers visiting family are the ones malaria most often catches out, because they tend to skip the prevention medicine. The parasite is mainly Plasmodium falciparum, resistant to chloroquine, and the local malaria mosquito bites at night. Wear long sleeves after dark, put on repellent before sunset and sleep under an intact net or in a screened room, checking the net when you arrive.
Dengue and the daytime mosquitoes
The 2022–24 dengue outbreak was the country's first reported. A national analysis counted 1,264 laboratory-confirmed cases, 91.9% of them in 2022 and 68.2% in Água Grande, the district of São Tomé city. Rainfall explained most of the rise and fall, and 2022 was exceptionally wet. WHO listed the outbreak as over by December 2023, but named the country again among those with active dengue transmission in January–April 2024. There are no figures for 2025 or 2026.
Two day-biting carriers, Aedes aegypti and the tiger mosquito, Aedes albopictus, are established on the islands. They bite in daylight, with peaks after sunrise and in the late afternoon, so repellent goes on over sunscreen in the morning and again before garden, forest and plantation walks. Our dengue & Zika routine has the schedule.
When to go
The gravana, the main dry season, tends to run roughly June to September and brings the fewest mosquitoes. The long rains, roughly October to May, tend to bring the most, and the 2022 dengue outbreak began in April, in a year of exceptional rain. CDC's malaria advice applies in every month.
Where you're going
São Tomé city
Água Grande, the capital's district, held 68.2% of the 2022–24 dengue cases, so daytime repellent matters most here. CDC's malaria advice covers the city too.
Príncipe's lodges
Malaria is rare on Príncipe, with 34 cases in 2024, but CDC's medicine advice covers both islands. Keep the dusk routine and check the net at the lodge.
The roças & Monte Café
Garden and forest walks tend to bring daytime bites, so reapply before you set out. Skip swimming in river pools and under waterfalls, where CDC warns about schistosomiasis.
Combining the islands with the mainland? Our Gabon briefing covers the next stop.
The São Tomé and Príncipe kit
- Picaridin 20% travel sprays: odorless in the humidity and quick to reapply before a plantation walk. One 3.4 oz bottle lasts one person about a week.
- Permethrin 0.5% for clothing: treat a long-sleeved shirt and trousers at home 48 hours before you fly. Clothing only, never skin.
- A compact bed net for rooms where the net has holes or there isn't one.
What travelers report
Paraphrased from TripAdvisor forum threads and linked so you can read them in full. Bites change with the season and where you stay.
- São Tomé (botanical garden walk) · May · 2022
A two-week May visitor was eaten alive by mosquitoes walking through a botanical garden one afternoon, found them extremely aggressive at sunset, and noted a dengue outbreak during the trip; heavy, constant DEET kept it manageable. TripAdvisor ↗
- São Tomé and Príncipe
In a thread on malaria risk, one traveler said they had heard malaria was only on São Tomé, not Príncipe, skipped pills and were fine, while another poster pointed out that international travel health sites rate the risk as high on both islands. TripAdvisor ↗
Two last notes. CDC says schistosomiasis is found in the islands' fresh water, so skip river pools and waterfall swims on plantation hikes. And any fever during or after your trip needs prompt care and a malaria test, and you tell the doctor you were in São Tomé and Príncipe. After time in a malaria area, that rule holds for a year.
Traveler questions
Do I need malaria pills for Príncipe?
CDC's recommendation covers all of São Tomé and Príncipe, listing the transmission areas as "All," with no exception for Príncipe. Transmission there is very low: WHO reported 34 cases on Príncipe in 2024 and 3 by March 2025. Which medicine suits you, and how it fits a trip across both islands, is a call for a travel clinic, made 4–6 weeks before departure with your full itinerary. Our malaria-zone checklist covers the rest.
Is dengue still a risk on São Tomé?
CDC lists dengue for São Tomé and Príncipe. The country's first reported outbreak began in April 2022, and a national analysis counted 1,264 laboratory-confirmed cases from 2022 to 2024, nearly all in 2022 and most in São Tomé city. WHO listed the outbreak as over by December 2023, then named the country again among those with active dengue transmission in January–April 2024. There are no figures for 2025 or 2026. The mosquitoes that spread it bite in daylight, so wear repellent from the morning on.
Do I need a yellow fever vaccine for São Tomé and Príncipe?
CDC says "Vaccine is generally not recommended for travel to São Tomé and Príncipe," and it isn't required on a direct trip from the US. Proof is required from travelers 1 year or older arriving from a country with yellow fever risk, including airport transits or layovers of more than 12 hours there, so bring your full routing to the travel clinic if your flights connect through another country.
Sources
Health authorities, surveillance reports and news coverage of official bulletins used for this briefing, last checked October 2026. Traveler reports are linked where they appear. This page summarizes public-health guidance and is not medical advice.
- CDC destination page for travelers
- World Health Organization
- World Health Organization
- World Health Organization
- Peer-reviewed study (PubMed Central)
- Peer-reviewed study (PubMed Central)
- Peer-reviewed study (PubMed Central)
- World Health Organization
- World Health Organization
- World Health Organization
- World Health Organization
- World Health Organization
- ocidadao.pt
- Peer-reviewed study (PubMed Central)
- Peer-reviewed study (PubMed Central)