Dengue figures with their dates, the chikungunya risk guidance lists, where malaria occurs, why yellow fever vaccination is not recommended, and how to time your protection against day-biting and night-biting mosquitoes in Mexico.
What the newest dengue figures show, and when they were published
Dengue numbers for Mexico move quickly, so the date behind each figure matters more than the figure alone. The Pan American Health Organization published a regional report on 23 October 2026 with data to epidemiological week 39. Mexico recorded 58,549 cumulative suspected cases through week 39 and 1,521 suspected cases in week 39. Across the Americas, PAHO counted 1,813,577 suspected cases, 565,945 laboratory-confirmed cases and 614 deaths, a case fatality rate of 0.034 percent. PAHO also reported 28,008 new suspected cases in week 39, including 76 classified as severe dengue and 10 deaths. The regional total sat 55 percent below the same period in 2025 and 62 percent below the five-year average, which is encouraging context rather than a reason to relax.
Mexico's own count uses a different series
Mexico's federal health ministry, the Secretaría de Salud, publishes its own weekly dengue panorama. The week 41 edition, dated 22 October 2026 with data to 19 October 2026, reports 8,047 confirmed dengue cases and 33 deaths, a case fatality rate of 0.82 per 100 cases. It states that 63 percent of confirmed cases were in Sonora, Veracruz, Tabasco, Sinaloa and Quintana Roo. That count differs sharply from PAHO's laboratory-confirmed figure for Mexico of 5,859 cases to week 37, because the two cover different weeks and use different case definitions. Read each series on its own terms and never subtract one from the other. The national panorama is the country's own count and covers a later week than the regional report.
Chikungunya: a listed risk without a Mexican case count
TravelHealthPro's Mexico country page states that there is a risk of dengue, a risk of Zika virus and a risk of chikungunya in Mexico. It gives no country-specific outbreak history for any of the three and no sub-national detail for Zika. The page is general country information rather than a notice tied to a single outbreak. PAHO's 20 October 2026 update records 213,919 suspected and 78,481 confirmed chikungunya cases in the Americas, with 88 deaths in 20 countries and territories. Its country section covers Argentina, Bolivia, Brazil, Costa Rica, Cuba, French Guiana, Guyana, Panama and Suriname, and gives no Mexican chikungunya figure. So chikungunya appears as a listed risk for Mexico without a matching national count in these sources. Treat the listing as a reason to plan bite avoidance, not as a measured local rate.
Where malaria occurs in Mexico
The two main authorities frame malaria risk in Mexico differently, and the difference is useful. The World Health Organization's World malaria report 2025, published on 4 December 2025, estimates 266 malaria cases and one death in Mexico in 2024. It records 880 confirmed cases in the country that year, with P. vivax as the main species, and 226 indigenous cases. CDC's Mexico destination page places malaria risk in Campeche, Chiapas and the southern part of Chihuahua state, and records the disease as rare in Oaxaca, Sinaloa, Sonora and Tabasco. CDC states there is no malaria transmission on the United States to Mexico border and recommends prescription medicine for travellers to certain areas. TravelHealthPro describes a very low risk nationally without naming areas. For itinerary planning, the sub-national detail is the more actionable of the two.
Why yellow fever vaccination is not recommended
Yellow fever vaccination is not recommended and not required for travel to Mexico. CDC's Mexico page records both points plainly: the vaccine is not recommended for the country and not required for entry. TravelHealthPro's Mexico page has no yellow fever disease section at all, and its certificate section states that there are no certificate requirements under the International Health Regulations. In practice, that means a yellow fever certificate should not be demanded at the border on the basis of these sources. Some travellers still ask for the vaccine out of habit. The relevant question is whether a traveller's route passes through a country with a yellow fever requirement before reaching Mexico, which is a separate itinerary question for a travel health professional rather than a Mexican entry rule.
Which mosquitoes bite by day and which by night
Biting times decide how you plan a day. TravelHealthPro's factsheet 38, updated 13 August 2026, states that some mosquitoes bite during daylight hours, including Aedes species, while others are more active from dusk to dawn, including Anopheles species. Aedes aegypti can also bite at night in well-lit areas, and Anopheles can be active during the day, at dawn and dusk, and throughout the night depending on species and place. The World Health Organization's chikungunya fact sheet, updated 14 April 2025, says the mosquitoes that spread chikungunya bite primarily during daylight hours, and that Aedes aegypti feeds both indoors and outdoors. A daytime terrace lunch, a shaded courtyard or an open-air market therefore carries its own risk, separate from the evening.
Repellent, screens and when a bed net matters
Repellent containing DEET at 50 percent concentration is recommended for all travellers over two months, provided it can be tolerated. TravelHealthPro's factsheet 38 says protection does not increase beyond 50 percent, that icaridin has similar properties at 20 percent, and that DEET goes on after sunscreen, with a 30 to 50 SPF sunscreen in use. DEET is not recommended under two months. WHO recommends repellents containing DEET, IR3535 or icaridin, applied according to the product label. A bed net matters most in malaria-endemic areas: travellers should sleep under one unless the room is well screened or has working, switched-on air conditioning where mosquitoes cannot enter. WHO advises insecticide-treated nets for people who sleep during the daytime. Babies under two months should be protected with clothing and treated nets draped over cots and prams, secured around the edges.
Sources
- Report on the epidemiological situation of dengue in endemic countries of the Americas, as of epidemiological week 39, 2026: Pan American Health Organization / World Health Organization
- Epidemiological Update: Dengue and Chikungunya in the Americas Region, 20 October 2026: Pan American Health Organization / World Health Organization
- Mexico country information: TravelHealthPro (UK National Travel Health Network and Centre)
- Mexico, CDC Travelers' Health: US Centers for Disease Control and Prevention
- Insect and tick bite avoidance: TravelHealthPro (UK National Travel Health Network and Centre)
- Chikungunya (fact sheet): World Health Organization
- Panorama Epidemiológico de Dengue, Semana Epidemiológica 41 de 2026: Secretaría de Salud, Mexico
- World malaria report 2025: World Health Organization
This article is general information, not medical advice. Ask a doctor or pharmacist about your own health.