Mosquitoes in the Cook Islands: Rarotonga's Dengue Outbreak & Aitutaki (2026)

Te Marae Ora declared the Rarotonga outbreak over in May 2026 after 1,251 cases and one death, and weekly reports have stayed near zero since. December to April is the wet season, when that outbreak surged, so check the current status before you fly and keep daytime repellent in the beach bag.

Are there mosquitoes in the Cook Islands? Yes, including the day-biting Aedes that spreads dengue. A dengue outbreak centered on Rarotonga ran from May 2025 to May 2026 and is over, and there is no malaria. A December–April trip falls in the wet season, when that outbreak peaked, so plan on daytime repellent and check the current status before you fly.

Disease risk ModerateRarotonga's 2025–26 dengue outbreak ended in May 2026 and reports have stayed near zero since; CDC also lists Zika, and there is no malaria.

Bite nuisance NoticeableRarotonga's breezy coast tends to be light, while the forested interior and Aitutaki tend to bite more, especially on calm, humid days.

CirculatingDengue (outbreak over, May 2026)Zika (CDC: no outbreak)No malariaNo CDC travel noticeNo yellow fever vaccine

CDC noticesNo country-specific notice for mosquito-borne disease

Dec–Apr tripsDecember to April is the wet season, when the 2025–26 outbreak surged, with its sharpest jump in late January. Reports have been near zero since March 2026, so check Te Marae Ora's latest dengue update before you fly.

Data checkedOctober 2026 · sources

The 2025–26 outbreak, and what to check now

Te Marae Ora, the Cook Islands health ministry, declared a dengue outbreak on Rarotonga on May 22, 2025. Cases grew slowly through the year, with a rise in July linked to the Te Maeva Nui festival, then surged in the wet season. The World Health Organization's Pacific surveillance recorded 177 reports of dengue-like illness in one week in late January 2026, down to 1 a week by early March. Aitutaki's last positive case came on March 20, and the country's last on April 28. When the ministry declared the outbreak over on May 25, 2026, it counted 1,251 cases and one dengue-related death.

The islands have been quiet since. WHO's weekly Pacific reports stayed near zero into October 2026, and the Cook Islands have no CDC travel notice and aren't on the CDC's global dengue list. Dengue has come back to the islands repeatedly, though, and the last outbreak surged in the same months a winter trip covers. Check Te Marae Ora's dengue page and WHO's Pacific dengue update the week before you fly.

The routine is the same either way. Aedes mosquitoes bite in daylight, with peaks after sunrise and in the late afternoon. Put repellent on over sunscreen in the morning, again after a lagoon swim and before sunset, and pick a screened or air-conditioned room. Our dengue & Zika routine has the full schedule. The CDC also lists Zika for the Cook Islands, with no current outbreak, so if you're pregnant, talk to a healthcare provider before the trip.

The coast, the Cross-Island Track and Aitutaki

Where you spend the day changes the bite count. Rarotonga's lagoon-side coast, from Muri around the south shore, tends to be light when the trade winds blow. The forested interior tends to be much worse, so put repellent on at the start of the Cross-Island Track and wear long, light clothing for the hike. Town gardens in Avarua get the daytime biters too. Aitutaki has a reputation for more mosquitoes than Rarotonga, and it had cases in the outbreak. Calm, humid days and the wet months tend to be the buggiest everywhere.

The CDC also lists leptospirosis, which isn't spread by insects and is more likely in the wet season. Avoid wading in floodwater, fresh water or mud after heavy rain.

Where you're going

How Rarotonga and Aitutaki compare for a December–April trip.

resort

Muri & Rarotonga's south coast

Disease risk ModerateBite nuisance Occasional

Rarotonga was the center of the 2025–26 outbreak, which ended in May 2026. The breezy lagoon-side coast tends to be lighter on mosquitoes than the interior, but dengue mosquitoes bite by day, so the morning repellent stays.

city

Avarua & the Cross-Island Track

Disease risk ModerateBite nuisance Noticeable

Town gardens and the forested inland track, where mosquitoes tend to be much heavier than on the coast. Put repellent on at the trailhead and wear long, light clothing for the hike.

island

Aitutaki

Disease risk ModerateBite nuisance Noticeable

Aitutaki had cases in the outbreak too, with its last positive case on March 20, 2026, and it has a reputation for more mosquitoes than Rarotonga. Bring enough repellent for the whole stay.

Island-hopping across the Pacific? Our Tahiti, Samoa and Fiji briefings cover dengue on those islands.

The Cook Islands kit

Small and simple. Add the backup for Aitutaki, a family or a long stay.

Picaridin 20% travel sprays: odorless, layers over sunscreen and quick to reapply after a swim in Muri lagoon. One 3.4 oz bottle covers about a week of daily use for one person.
A full-size backup in the checked bag. Daytime use for dengue empties a travel bottle faster than evening-only spraying, especially if you add a few nights on Aitutaki.
Light long pants and sleeves for the Cross-Island Track, where the forest is buggier than the beach.

Carry-on trio → 8 oz backup → Full rankings

What travelers report

Paraphrased from an older TripAdvisor thread and linked so you can read it in full. It isn't dated, and the trade winds change the picture from one day to the next.

Rarotonga and Aitutaki · April (trip-planning thread)
A poster said mosquitoes are generally worse on Aitutaki than on Rarotonga, and are heavy inland in the forest while the coast is usually fine when the trade winds blow. Another poster noticed more insects overall on Aitutaki. This is an older thread. TripAdvisor ↗

One rule outlasts the trip. Any fever during or after your trip means a doctor visit, and you tell them you were in the Cook Islands, especially if it comes with headache, rash or body aches.

Traveler questions

Is there dengue in the Cook Islands right now?

Not at outbreak levels. Te Marae Ora, the health ministry, declared the Rarotonga outbreak over on May 25, 2026, after 1,251 cases and one dengue-related death, and the World Health Organization's weekly Pacific reports stayed near zero into October 2026. Dengue has returned to the islands before, and the last outbreak surged in the December–April wet season, so check the ministry's dengue page the week before you fly.

Is Aitutaki buggier than Rarotonga?

It has that reputation. Aitutaki tends to have more mosquitoes than Rarotonga, while Rarotonga's coast is usually light when the trade winds blow. On Rarotonga, the forested interior, including the Cross-Island Track, tends to be the buggiest part of the island. Aitutaki also had cases in the outbreak, with its last positive case on March 20, 2026.

Do I need malaria pills or a yellow fever vaccine for the Cook Islands?

No. The CDC lists no malaria for the Cook Islands and recommends no malaria medicine. The yellow fever vaccine is not recommended, and the Cook Islands don't require it.

Is it safe to visit the Cook Islands while pregnant?

The CDC lists Zika for the Cook Islands, as an area with current or past transmission and no current outbreak. Zika can pass from a pregnant woman to her baby, so talk to a healthcare provider 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.

The Cook Islands' dengue outbreak is over. A winter trip lands in the season it peaked.