All of Chiapas and Campeche carry CDC malaria advice. The bites live in the forest.

Are there mosquitoes in Chiapas? Plenty in the lowland rainforest around Palenque and at Calakmul in neighboring Campeche, and few in cool, high San Cristóbal de las Casas. The CDC recommends malaria prevention medicine for both states whole, so the trip starts with a travel-clinic visit.

Malaria: both states, in the CDC's words

The CDC's Mexico page says, "CDC recommends that travelers going to certain areas of Mexico take prescription medicine to prevent malaria," and names those areas as "Campeche, Chiapas, and the southern part of Chihuahua state." It marks no smaller zones inside the two southern states, so the advice covers Palenque, San Cristóbal and Calakmul alike. Its options are "Atovaquone-proguanil, chloroquine, doxycycline, mefloquine, primaquine, tafenoquine," and the last two need a G6PD blood test first.

Mexico's weekly bulletin counted 172 malaria cases in 2026 through early October, all in Chiapas, against 135 at the same point of 2025, and 14 came in a single week. Campeche reported none in either year. The bulletin gives no town breakdown, and press reports have placed recent cases in highland and northern communities rather than the tourist towns. Malaria mosquitoes bite from dusk to dawn.

Sand flies, and Campeche's leishmaniasis jump

The forest's other biter is the phlebotomine sand fly, which bites from dusk to dawn and can spread cutaneous leishmaniasis, a skin infection. Campeche reported 64 cases in 2026 through early October, against 9 at the same point of 2025, according to Mexico's bulletin, and Chiapas held at 5. The CDC's Mexico page now carries a banner saying "Mexico is reporting increased cases of cutaneous leishmaniasis," and advises travelers to "stay in air-conditioned or well-screened indoor areas, wear clothing that minimizes exposed skin" and use an EPA-registered repellent.

These sand flies can slip through ordinary mosquito netting. At Calakmul and in the cabañas on the road to Palenque's ruins, check screens and nets for holes, use a permethrin-treated net in rustic rooms and keep long sleeves on after dark. Check for ticks after forest walks.

Dengue, and the daytime routine

Both states run above Mexico's dengue rate, at 7.45 and 7.28 confirmed cases per 100,000 people against 5.99 nationally. By October 19, 2026, Chiapas had 461 confirmed cases, below the 626 at the same point of 2025, and Campeche had 70, more than double its 33 a year earlier, with 5 in Calakmul municipality. Palenque and San Cristóbal were not among the named municipalities in 2025 or 2026. Chiapas also had 9 of Mexico's 15 local chikungunya cases this year through early October.

The mosquito behind both, Aedes, bites by day, so repellent goes on over sunscreen in the morning, again before dusk and after every swim at the Agua Azul and Misol-Ha waterfalls. December to April is dry and dengue's low point, though in 2025 a fifth of Chiapas's confirmed cases came after mid-October, so early December can catch the tail.

Where you're going

Scores are for a December–April trip. The CDC's advice is the same at every stop.

The Mexico briefing compares every region. Crossing into Guatemala? Our Tikal & Flores briefing covers Petén.

What travelers report

Paraphrased from TripAdvisor forum threads and reviews and linked so you can read them in full. The one dated review is from 2013 and the others are undated, so read them for where the bites happen rather than for this season.

• Rio Bec Dreams Hotel, Calakmul · review posted mid-December · 2013

  A guest said the cabins, charming in photos, were very basic, that bed nets were essentially absent and that mosquitoes were a serious nuisance, though the hotel was still a practical base for visiting Calakmul. TripAdvisor ↗

• Palenque (ruins, national park and the road to the ruins)

  A poster said mosquitoes are mainly a problem in the forested areas: the hotels and restaurants along the road to the ruins, the ruins themselves and the national park. The town itself was not really a problem. TripAdvisor ↗

• El Panchán, Palenque

  A guest in a jungle cabaña reported torn screens that let in large spiders, lizards and mosquitoes. TripAdvisor ↗

One rule outlasts the trip. Any fever during your trip or in the year after it means a doctor visit, and you tell them you were in Chiapas or Campeche. The same goes for a bite sore that won't heal.

Traveler questions