The Centres for Disease Control and Prevention (CDC) has issued a warning to American tourists regarding a chikungunya outbreak in Costa Rica, a popular beach holiday destination. On 16 July, the CDC raised the alert level for the country to Level 2, urging travellers to “practice enhanced precautions” as the mosquito-borne virus begins to spread.
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Costa Rica’s Ministry of Health declared an active outbreak of chikungunya in Playa Langosta, located in the Guanacaste province, on 1 July. An epidemiological assessment later revealed 45 suspected cases of the virus, with four confirmed through laboratory tests. Additionally, 17 more infections were identified as likely related to the outbreak.
Playa Langosta, known for its serene beaches, is now on the radar for health authorities. Cases have been reported among both Costa Rican residents and foreign visitors, indicating local transmission is occurring. This means that the virus is no longer solely arriving via international travellers but is being circulated by mosquitoes within the area.
Overall, Costa Rica has reported a total of 16 chikungunya cases this year, which include those linked to the current outbreak. This marks a notable resurgence of the virus, as there had been no recorded cases in the country since 2017.
Chikungunya is transmitted to humans through bites from infected mosquitoes, particularly the Aedes aegypti species. This same mosquito is responsible for spreading dengue fever and Zika virus. Symptoms of chikungunya can include fever, severe joint pain, headaches, muscle pain, swelling of joints, and rashes. The initial week of infection is critical, as individuals can spread the virus to mosquitoes during this time.
In light of the outbreak, both the CDC and the U.S. Embassy in Costa Rica have emphasised the importance of preventive measures against mosquito bites. Despite the existence of a vaccine in the U.S., it is not widely available or recommended for travellers at this time. Therefore, the agencies have advised individuals to apply EPA-registered insect repellents, wear protective clothing like long sleeves and trousers, and to stay in air-conditioned or screened spaces whenever possible.
This recent outbreak aligns with global trends observed by health authorities. Earlier in the year, the Pan American Health Organisation issued an epidemiological alert due to a noticeable increase in chikungunya cases worldwide. Between January and December 2025, over half a million cases of the disease were reported across 41 countries, resulting in approximately 186 fatalities.
In March, the European Centre for Disease Prevention and Control reported more than 32,000 chikungunya infections in just the first two months of 2026. There was also a significant local transmission case confirmed in New York State, marking a historic first for the area since local transmission had not been reported in the U.S. since 2019.
Although chikungunya is rarely fatal, its long-term effects can be debilitating for those who contract it. A study conducted six years after the initial onset of symptoms revealed that many patients continued to experience chronic joint pain, which severely affected their quality of life. Some individuals reported needing orthopaedic footwear, and many suffered from persistent fatigue.
As the outbreak in Playa Langosta continues to evolve, health officials are urging travellers to remain informed and vigilant. The CDC’s warning highlights the necessity of precaution in order to protect oneself from potential health risks associated with the disease while travelling.