Dengue fever is a viral infection that is spread to humans primarily by the bite of female Aedes mosquitoes, which favor densely populated areas, and also rural environments. In Ecuador, dengue fever occurs most often in the coastal provinces, more frequently during warm, humid seasons.

Mosquitoes that spread dengue are daytime feeders with 2 peaks of biting activity during the day: the first 2-3 hours after dawn and the mid-to-late afternoon hours, and is usually more active throughout the day during the rainy season. The risk is higher for those staying in inappropriately conditioned facilities (like places with nearby stagnant water reservoirs and no mosquito protection)

There is no vaccine against dengue, so travelers to dengue-endemic areas must use repellents and take other preventive measures at all times, being especially vigilant during early morning and late afternoon hours. Travelers to areas where insects that transmit diseases may be present can help minimize their risk by following these precautions:

- If you are not sleeping in a sealed, air-conditioned room, use a bed net, preferably impregnated with insect repellent, with edges tucked under the mattress.

- Apply insect repellent to exposed skin, avoiding eyes, mouth and open wounds. Frequent application ensures continuous protection. Insect repellent may also be applied to clothing.

- Wear long sleeves, long pants, hats and shoes rather than sandals.