Mosquitoes in Gabon: Malaria, Tsetse, Eye Worm & the Forest Kit (2026)

The CDC recommends malaria prevention medicine for all of Gabon, and Gabon checks yellow fever proof from every arriving traveler 9 months and older. In Loango, Lopé and the mangroves near Libreville, tsetse flies and deer flies bite by day, and a 2025 trial in Gabon changes which repellent to carry.

Are there mosquitoes in Gabon? Yes, in every month, and the CDC recommends malaria prevention medicine for the whole country, Libreville, Port-Gentil, Lambaréné and the Loango and Lopé parks included. Gabon also requires proof of yellow fever vaccination from every arriving traveler 9 months and older. In the forest and mangroves, day-biting tsetse flies and deer flies, which spread sleeping sickness and the African eye worm, need their own plan.

Disease risk ElevatedCDC recommends malaria medicine for all of Gabon and yellow fever vaccine from 9 months, which Gabon requires at entry; tsetse spread sleeping sickness and deer flies spread eye worm in forest areas.

Bite nuisance NoticeableWith no traveler reports to go on, forest parks such as Loango and Lopé tend to add day-biting tsetse, deer flies and horse flies to the mosquitoes.

CirculatingMalaria (all areas)Sleeping sickness (tsetse)Eye worm (deer flies)Yellow fever (suspected cases, 2026)No dengue reports in 2024 or 2026Chikungunya vaccine generally not advised

CDC noticesNo country-specific notice for mosquito-borne disease

Travel clinicCDC recommends malaria medicine for all areas of Gabon and yellow fever vaccine for all travelers 9 months and older, and Gabon requires proof of vaccination from all arriving travelers 9 months and older. CDC says chikungunya vaccination is generally not recommended. See a travel clinic 4–6 weeks before you fly.

When to goThe long dry season, roughly June–September, tends to bring the fewest mosquitoes and is the usual park season. The heavy rains, roughly October–November and February–May, tend to be the worst. Tsetse and deer flies bite by day in the forest in any month, and malaria medicine applies year-round.

Data checkedOctober 2026 · sources

Malaria and yellow fever: the clinic visit

The CDC's wording is "CDC recommends that travelers going to Gabon take prescription medicine to prevent malaria." Transmission occurs in all areas, mostly Plasmodium falciparum resistant to chloroquine. The CDC notes that people visiting friends and relatives are at higher risk because they often skip prevention medicine. Malaria mosquitoes bite from dusk to dawn, so repellent at sunset and a screened or air-conditioned room or a bed net cover the night.

What we suggest you do with this: the CDC recommends malaria medicine for all areas of Gabon, and for yellow fever, "Vaccine is recommended for all travelers ≥9 months old." Gabon's entry rule is "Vaccine is required for all arriving travelers ≥9 months old," including on a direct flight from the US. CDC says chikungunya vaccination is generally not recommended. Book a travel-medicine appointment 4–6 weeks before departure and mention any forest or mangrove plans. Our malaria-zone checklist covers the rest.

Tsetse and deer flies bite by day

CDC lists African sleeping sickness for Gabon, and WHO puts the country at 10 to 100 cases a year. The most active focus, Komo-Mondah in the province around Libreville, averages about 20 cases a year, with mangrove boat landings the main contact points. A 2012 report described an expatriate infected in town, after a probable tsetse bite in his garden in Libreville's Lalala district.

Peer-reviewed studies document the African eye worm, loiasis, which isn't on CDC's Gabon page. Day-biting deer flies (Chrysops) carry it, and a survey of adults in 212 villages from 2005 to 2008 found 22.4% infected, with the highest rates in forest areas. In a 2025 trial in Gabon, DEET and oil of lemon eucalyptus (OLE/PMD) repellents each cut deer-fly bites by about half, while picaridin and IR3535 had no effect. That trial is why the Gabon kit below leads with DEET or OLE instead of the picaridin we usually recommend.

CDC lists dengue and Zika for Gabon, and Libreville's 2007 outbreak of about 20,000 suspected chikungunya and dengue cases was spread mainly by the day-biting Asian tiger mosquito, a CDC journal reported. CDC also lists Ebola, so don't handle bushmeat or dead animals, and says schistosomiasis is found in Gabon, so stay out of fresh water.

When to go

The long dry season, roughly June to September, tends to bring the fewest mosquitoes and is the usual time for park visits. The heavy rains, roughly October to November and February to May, tend to be the worst. Tsetse and deer flies bite in any month, and malaria medicine applies year-round.

Where you're going

city

Libreville

Disease risk ElevatedBite nuisance Noticeable

Inside CDC's malaria advice with no city exception, and the center of the 2007 chikungunya and dengue outbreak. Komo-Mondah, the most active sleeping-sickness focus, is in the same province, so cover up by day at mangrove landings and waterside spots.

safari

Loango National Park

Disease risk ElevatedBite nuisance Annoying

Lagoon, forest and savanna in Ogooué-Maritime, a province where wildlife sampled from 2019 to 2022 carried the human sleeping-sickness parasite. Tsetse and horse flies tend to work the forest edges by day, so wear treated long sleeves and DEET or OLE.

safari

Lopé National Park

Disease risk ElevatedBite nuisance Annoying

Forest and savanna in central Gabon. Tsetse and deer flies are documented in Gabon's other forest parks, so plan on long sleeves and DEET or OLE for walks. CDC's malaria advice applies here too.

Heading to the Republic of the Congo or Cameroon? Our Republic of the Congo and Cameroon briefings cover the next border.

The Gabon forest kit

Not our usual picaridin pick, because of the 2025 deer-fly trial in Gabon.

Oil of lemon eucalyptus 30%, or a DEET repellent: the two that cut deer-fly bites by about half in the Gabon trial. Both also work against mosquitoes, so one spray covers town evenings and forest days. OLE isn't for children under 3.
Permethrin 0.5% for long sleeves and trousers: treat loose, long clothes at home 48 hours before you fly and wear them by day in the forest, where covering up is the defense against tsetse and deer flies. Clothing only, never skin.

OLE 30% → Permethrin → Full rankings

One more rule outlasts the trip. Any fever during or after your trip means a doctor visit, and you tell them you were in Gabon. Mention forest time, and sleeping sickness as well as malaria, if a painful, swollen bite or sore appears in the weeks after. Itchy, moving swellings or a worm in the eye later on point to the eye worm.

Traveler questions

Is there sleeping sickness in Gabon?

Yes. The CDC's Gabon page lists African sleeping sickness, spread by tsetse flies, and WHO puts Gabon at 10 to 100 cases a year. The Komo-Mondah focus, in the province around Libreville, averages about 20 cases a year, and a 2012 report described an expatriate infected after a probable tsetse bite in his Libreville garden. Tsetse bite by day, so cover up in forest and mangrove areas, and tell a doctor about a painful, swollen bite or sore in the weeks after your trip.

Why DEET or lemon eucalyptus for Gabon instead of picaridin?

Because of deer flies, which spread the African eye worm. In a 2025 randomized trial in Gabon, DEET and oil of lemon eucalyptus (OLE/PMD) repellents each cut deer-fly bites by about half, while picaridin and IR3535 had no effect. Picaridin still works against mosquitoes, which is why we usually recommend it. For Gabon's forests, DEET or OLE covers mosquitoes and deer flies alike. Our picaridin vs. DEET comparison explains the general trade-offs.

Do I need a yellow fever vaccine for Gabon?

Gabon requires proof of it. The CDC's recommendation is "Vaccine is recommended for all travelers ≥9 months old," and Gabon's entry requirement is "Vaccine is required for all arriving travelers ≥9 months old." That applies on a direct flight from the US, so carry the yellow International Certificate of Vaccination with your passport. WHO reported suspected cases under investigation in Gabon from January to May 2026.

Do I need malaria pills for Libreville?

The CDC recommends malaria prevention medicine for all of Gabon, Libreville and every park included, with no exception for cities or the dry season. CDC notes that people visiting friends and relatives are at higher risk because they often skip prevention medicine. Which medicine fits you is a call for a travel clinic, made 4–6 weeks before departure. Our malaria-zone checklist covers the rest.

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.

In Gabon's forests, the day-biting flies matter as much as the mosquitoes.