The chikungunya outbreak in Seychelles has become one of the most relevant epidemiological events in the Indian Ocean in 2026, with active transmission across the archipelago and growing repercussions among international travelers.
From November 2025 through 13 March 2026, more than 110 travel-related chikungunya cases have been reported in 13 EU/EEA countries among people returning from Seychelles. This increase represents a significant epidemiological shift, as no imported cases linked to this destination had been reported in previous years.
An autochthonous outbreak with international projection
Available information indicates that Seychelles is experiencing a period of active chikungunya transmission with the capacity to export cases to other countries. Local health authorities have also noted that, in the current context, chikungunya virus is now more prevalent in Seychelles than other circulating arboviruses, reinforcing its role as the country’s main ongoing vector-borne event.
The epidemiological importance of this outbreak lies not only in local transmission, but also in its ability to generate imported cases among travelers, especially in a destination with high international tourist connectivity. Seychelles received approximately 350,000 visitors last year, which facilitates the international spread of infections acquired during travel.
Magnitude and epidemiological interpretation
Available data point to sustained transmission in Seychelles and an increasing detection of cases among travelers during the first months of 2026. The accumulation of more than 110 imported cases in Europe constitutes a strong signal of epidemic activity at the destination.
From an epidemiological perspective, this pattern suggests several key elements:
- active community circulation of the virus;
- traveler exposure at different moments throughout the epidemic period;
- persistence of infection risk during the peak travel season;
- possible underdetection of the true magnitude of the local outbreak when compared with the signal observed in international travelers.
In this sense, travelers are acting as epidemiological sentinels, providing an indirect but very useful signal of transmission intensity in Seychelles.
Regional context: Indian Ocean
The situation in Seychelles should not be interpreted in isolation. The emergence of this outbreak is part of a broader regional expansion of chikungunya in the Indian Ocean, particularly following the major outbreak reported in Réunion in 2025. Events related to travelers or regional circulation have also been reported in connection with Mauritius, Mayotte, and Comoros, suggesting a scenario of increased arboviral activity across the islands of the region.
This regional context is epidemiologically relevant because it favors reintroduction, local amplification, and the emergence of transmission chains in island territories with ecological conditions suitable for Aedes mosquitoes.
Risk for travelers
The ECDC considers the likelihood of chikungunya infection for travelers to Seychelles to be high, particularly during the peak tourism period between February and April. This assessment is consistent with the persistence of the outbreak and the growing number of travel-associated cases.
By contrast, the risk of secondary transmission in mainland Europe is currently considered low, because environmental conditions at this time of year are generally unfavorable for Aedes mosquito activity across much of the continent.
Even so, imported cases remain epidemiologically relevant for several reasons: they reinforce the need for clinical vigilance, require health systems to remain alert, and may become more important in later months if seasonal conditions change in areas where vectors are present.
International response and recommendations
The evolution of the outbreak has prompted specific public health responses. On 5 February 2026, the U.S. CDC issued a Level 2 Travel Health Notice for Seychelles, recommending enhanced precautions in response to the active chikungunya outbreak.
The main recommendations focus on:
- strict protection against mosquito bites;
- pre-travel health information and advice;
- individual risk assessment;
- reconsideration of travel for pregnant women, especially close to delivery.
In addition, authorized chikungunya vaccines are now available in 2026, opening the possibility of considering vaccination for selected travelers, according to national recommendations, age, comorbidities, and expected type of exposure.
Clinical relevance
Chikungunya is an arboviral disease transmitted by Aedes mosquitoes and typically presents with:
- high fever,
- severe arthralgia,
- myalgia,
- headache,
- nausea,
- fatigue,
- rash.
Although mortality is low, the clinical impact can be substantial because of the frequency of persistent joint pain and subsequent functional limitation, especially in vulnerable individuals. There is no specific antiviral treatment, so management remains mainly supportive.
In summary … In 2026, Seychelles has become a relevant focus of chikungunya transmission in the Indian Ocean, with effects extending beyond its national territory due to the rise in imported cases among international travelers. The detection of more than 110 cases in travelers returning to Europe since November 2025 confirms the intensity of the event and reinforces the need for epidemiological surveillance, risk communication, and specific preventive measures for those traveling to the archipelago.
At present, Seychelles should be considered a destination with elevated epidemiological risk for chikungunya, particularly during the months of highest tourist mobility.
