All of Nicaragua is under a chikungunya notice. Here's the plan.
CDC's Level 2 notice covers the whole country, from San Juan del Sur to the Corn Islands, though cases were falling fast by October. A daytime repellent habit covers most of a trip, and the Caribbean side adds a malaria question.
Yes, and this year they matter more than usual. The CDC has a Level 2 chikungunya notice that covers the whole country, from San Juan del Sur to Ometepe and the Corn Islands. Cases were falling fast by October and the Pacific side is usually dry from December to April, so for most trips the plan is daytime repellent and a travel-clinic visit, plus a malaria question for the Caribbean coast.
The chikungunya notice
Chikungunya spreads through the same day-biting Aedes mosquitoes as dengue. Nicaragua's outbreak built from late May and peaked in August, with 1,840 cases in the health ministry's weekly releases, Nicaraguan press reported. In the week ending October 10, the ministry reported 25 people diagnosed. Independent Nicaraguan outlets say the official numbers miss cases.
The CDC's notice, last updated September 3, 2026, shades the entire country on its map, Ometepe and the Corn Islands included. CDC recommends vaccination for travelers visiting an area with a chikungunya outbreak and advises pregnant travelers to reconsider travel to affected areas, particularly close to delivery. Raise both at a travel clinic 4–6 weeks before departure. The notice may be updated or lifted before your trip, so check it again the week before you fly.
Dengue is endemic too, though official figures are sparse. The same routine covers both. Put repellent on over sunscreen in the morning and again in the late afternoon, and sleep in an air-conditioned or well-screened room. Our dengue & Zika daily routine has the full schedule. Costa Rica linked some of its imported cases in April to travel here, and our Costa Rica briefing covers the notice for its northwest.
The Caribbean side: Corn Islands and malaria
The CDC lists malaria prevention medicine for the two autonomous regions on the Caribbean side, the Región Autónoma Atlántico Norte (RAAN) and the Región Autónoma Atlántico Sur (RAAS). Big Corn and Little Corn are in RAAS, so the listing covers them. Elsewhere it reports rare cases in León and several other departments, with bite precautions only, and no transmission in Managua. Granada, San Juan del Sur and Ometepe are outside the medicine area.
What we suggest you do with this: if the Corn Islands or anywhere else on the Caribbean coast is on your route, book a travel-medicine appointment 4–6 weeks before departure and ask whether the CDC's malaria recommendation fits your stay. The chikungunya vaccine question fits in the same visit. Our malaria-zone checklist covers the rest.
Malaria mosquitoes bite from dusk to dawn, so on the islands add repellent at sunset, long sleeves for dinner and a screened room. No yellow fever vaccine is recommended, and none is required when you fly direct from the US. The CDC's Nicaragua page also lists New World screwworm and advises cleaning and covering all wounds.
Where the bites are
The Pacific side is the easier half. Mosquitoes on that coast tend to come out after sunset, and Granada's older houses and guesthouses have a reputation for more bites, so a screened or air-conditioned room is worth asking for. On the San Jorge ferry to Ometepe you may meet chayules, lake gnats that swarm for about three days and do not bite. On the Corn Islands, no-see-ums bite ankles at dawn and dusk and on calm days, and beaches on the windward side or cleaned daily tend to have fewer. Our sand fly guide explains the insect.
Where you're going
San Juan del Sur
Inside the chikungunya notice like the rest of the country, and outside the malaria-medicine area. Pacific-coast mosquitoes tend to come out after sunset, so add an evening application to the daytime habit.
Granada & León
Chikungunya notice area. León department has rare malaria cases with no medicine recommended. Older houses and guesthouses have a reputation for more bites, so ask for a screened or air-conditioned room.
Ometepe Island
Shaded on the CDC's chikungunya map. The gnat swarms around the San Jorge ferry and the lake are chayules, which don't bite.
Little Corn Island
In RAAS with Big Corn, so inside the CDC's malaria-medicine listing as well as the chikungunya notice. No-see-ums are worse on beaches away from the windward side and on those not cleaned daily.
The Nicaragua kit
- Picaridin 20% travel sprays: odorless in the heat, layers over sunscreen and deters both mosquitoes and beach no-see-ums. One 3.4 oz bottle covers about a week of daily use for one person.
- Permethrin 0.5% for evening clothes: treat a long-sleeved shirt and light trousers at home 48 hours before you fly, for the dusk-to-dawn hours on the Corn Islands.
One rule outlasts the trip. Any fever or joint pain during or after your trip means a doctor visit, and you tell them you were in Nicaragua, including whether the Corn Islands were on the route.
What travelers report
Paraphrased from forum threads and linked so you can read them in full. None is dated to this season and most of the threads are older, so weather, wind and where you stay can change the picture.
- Little Corn Island
Posters said staying on beaches that are cleaned daily and on the trade-wind side of the island keeps mosquitoes and no-see-ums down; one said they had not seen or heard a single mosquito during their stay. TripAdvisor ↗
- San Juan del Sur · evenings
A reply in an older thread said the Pacific coast is better than the Caribbean side for mosquitoes and that they only bother people after sunset. TripAdvisor ↗
- San Jorge-Ometepe ferry
A traveler described swarms of tiny flies on the ferry to Moyogalpa. A reply identified them as chayules, gnats that hatch, live about three days and disappear, and said they are very annoying but do not bite or sting. TripAdvisor ↗
- Granada
Experiences conflicted: one poster saw no mosquitoes in Granada or León the month before, while another was covered in bites after three days in a renovated house despite repellent; local advice was that some people get bitten and some do not. TripAdvisor ↗
Traveler questions
Should I get the chikungunya vaccine for Nicaragua?
CDC recommends chikungunya vaccination for travelers visiting an area with a chikungunya outbreak, and its current Level 2 notice covers all of Nicaragua. Whether it fits your trip is a question for a travel clinic, 4–6 weeks before departure. Cases had fallen to 25 in the week ending October 10, and the notice could be updated or lifted, so check it again the week before you fly.
Do I need malaria pills for the Corn Islands?
The CDC lists malaria prevention medicine for the Región Autónoma Atlántico Sur (RAAS), which includes Big Corn and Little Corn, and for the Región Autónoma Atlántico Norte (RAAN). Whether that adds up to a prescription for your stay is a call for a travel clinic, made with your exact dates. Granada, León, San Juan del Sur and Ometepe are outside the medicine area, and the CDC reports no malaria in Managua.
What are the swarms of tiny flies on the Ometepe ferry?
Chayules, lake gnats that hatch in swarms around Lake Nicaragua, live about three days and disappear. They can be very annoying on the San Jorge ferry, but they don't bite or sting.
Is it safe to visit Nicaragua while pregnant?
CDC advises pregnant travelers to reconsider travel to the areas covered by the chikungunya notice, particularly close to delivery, and the notice covers the whole country. The CDC's Nicaragua page also lists Zika, which can pass from a pregnant woman to her baby. Review both before you book.
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.