Throughout 2025, Chikungunya fever outbreaks have been reported in countries that border the Indian Ocean. From Madagascar to France's La Réunion Department, locally-acquired and travel-related cases have set new records.
To alert international travelers, the U.S. Centers for Disease Control and Prevention (CDC) recently issued a Level 2 - Practice Enhanced Precautions, Travel Health Notice regarding the Democratic Socialist Republic of Sri Lanka's ongoing Chikungunya fever outbreak.
Sri Lanka is located just south of India, home to about 21 million residents, and welcomed over 2 million visitors in 2024.
Earlier in 2025, a non-peer-reviewed study identified virus mutations that may be the source of these outbreaks.
These researchers wrote in May 2025 that the ongoing large outbreak in Sri Lanka is due to the Indian Ocean lineage and the E1:K211E/E2:V264A sublineage of the Chikungunya virus, which has acquired specific, previously uncharacterized mutations.
As of December 8, 2025, the CDC says that if you are pregnant, you should reconsider travel to the affected areas, particularly if you are close to delivering your baby. Mothers infected around the time of delivery can pass the virus to their baby before or during delivery.
Furthermore, newborns infected in this way or by a mosquito bite are at risk for severe illness, including poor long-term outcomes.
As of December 13, 2025, the CDC recommends vaccination with a U.S. FDA-approved vaccine for travelers visiting an area with a Chikungunya outbreak. Vaccines are commercially available at travel clinics in the USA.














