CDC expands Level 2 travel advisory as chikungunya spreads to new countries

The U.S. Centers for Disease Control and Prevention on Wednesday expanded a Level 2 travel health notice for chikungunya, adding Kenya, Madagascar, Somalia and Sri Lanka to a list of destinations where Americans are advised to take extra precautions against the mosquito-borne virus.

Since the beginning of 2025 more than 240,000 chikungunya cases and about 90 related deaths have been reported across 16 countries, public health authorities say. Cases have been identified in the Americas, Africa, Asia and Europe, and a severe outbreak in China that has topped 10,000 confirmed cases prompted an earlier Level 2 advisory for Guangdong Province in August.

Chikungunya is transmitted primarily by Aedes mosquitoes and is characterized by sudden onset of fever and intense joint pain, often in the hands and feet. The joint pain can be severe and, in some cases, persist for months and impair normal movement. While fatalities are uncommon, health authorities have linked multiple deaths to the current wave of global infections.

In its travel notice system, a Level 2 advisory means travelers should "practice enhanced precautions" at their destination. The CDC lists additional countries where U.S. travelers are at elevated risk of exposure, including Brazil, Colombia, India, Mexico, Nigeria, Pakistan, the Philippines and Thailand. The expanded advisory advises travelers to follow measures to reduce mosquito bites and consult health professionals before travel, especially those who are pregnant or have underlying health conditions.

Public health guidance for reducing risk centers on preventing mosquito bites: the use of EPA-registered insect repellent, wearing long sleeves and pants when feasible, staying in accommodations with window screens or air conditioning, and removing standing water where mosquitoes breed. Travelers who develop fever, rash or severe joint pain during or after travel are advised to seek medical attention and inform clinicians of their travel history.

Aedes mosquitoes, which also transmit dengue and Zika viruses, are established across many tropical and subtropical regions, enabling chikungunya to emerge in diverse geographies. The pattern of spread in 2025 reflects concurrent outbreaks and heightened transmission in multiple countries rather than a single source, health officials said in previous statements when issuing travel notices.

The CDC continues to update its travel health notices and recommends that travelers consult the agency’s website and local public health advisories for the latest information. Health professionals and travelers are being urged to monitor symptoms and follow prevention guidance as outbreaks evolve internationally.