What CDC Issued
Americans headed to one of Costa Rica's most popular beach regions now have a federal health notice attached to the trip.
The CDC Travel Health Notice places Costa Rica at Level 2, Practice Enhanced Precautions, because of a chikungunya outbreak in Guanacaste Province. Most cases have been reported in Playa Langosta, the beach community adjacent to Tamarindo in the Santa Cruz area.
Costa Rica's Ministry of Health declared the outbreak on July 1 after investigators reviewed 45 suspected cases, confirming four by laboratory testing and classifying 17 as probable. Those infected included both Costa Rican nationals and foreign visitors. The Health Ministry's national count for 2026 had risen to 21 cases as of July 21, up from 16 when the U.S. Embassy in San José issued its own alert on July 13.
Why This Matters
The phrase doing the work here is local transmission.
When a country reports imported cases, the virus arrived in a traveler's bloodstream and has not established itself. Local transmission means mosquitoes in that specific area are now carrying and spreading the virus themselves. Any Aedes mosquito on that stretch of coast can transmit it, not only one that happened to bite an arriving traveler.
That changes the calculation for every visitor to the area rather than a few unlucky ones. Guanacaste is a primary destination for American beach travel, and July and August fall inside peak booking season for U.S. families.
What Chikungunya Actually Does
Symptoms typically appear three to seven days after a bite. The hallmark combination is sudden high fever and severe joint pain, often accompanied by headache, muscle pain, joint swelling and rash.
The joint pain is what distinguishes it from the other mosquito-borne illnesses travelers worry about. Most people improve within a week, but a meaningful share experience joint pain that persists for months and, in some cases, years after the initial infection resolves. For a working adult, that is the outcome worth understanding before the trip.
Death from chikungunya is rare. CDC identifies newborns infected around the time of birth, adults 65 and older, and people with conditions such as diabetes or heart disease as facing higher risk of severe disease.
There is no specific treatment. Care is supportive: rest, fluids, and pain management.
The Vaccine Question
One point in most coverage of this notice is incomplete, and it matters for anyone booking a trip.
CDC's notice states that vaccination is recommended for travelers visiting an area with a chikungunya outbreak, and that healthcare providers should discuss the benefits and risks with individual travelers based on age, underlying health conditions, destination, trip duration and planned activities.
That is not the same as saying bite prevention is the only option. It does mean the decision is individualized rather than automatic, and availability varies. Anyone with a Guanacaste trip booked should raise it with a clinician or travel medicine clinic rather than assuming a vaccine is either unavailable or automatically appropriate.
CDC also advises that pregnant travelers reconsider travel to the affected areas, particularly if close to delivery. Where risk is high and exposure cannot be avoided, the agency says pregnant travelers should discuss the risks and the potential benefits and risks of vaccination with their provider.
Where the Risk Sits
The outbreak is concentrated in Playa Langosta and the wider Santa Cruz area, with Tamarindo immediately adjacent. The notice covers Guanacaste Province, which encompasses much of Costa Rica's northern Pacific coast and its most heavily visited beach towns.
Costa Rican authorities have fumigated approximately 5,000 homes and worked to eliminate mosquito breeding sites in an effort to contain the spread.
The regional picture is larger than one province. The Pan American Health Organization issued an epidemiological alert in February 2026 flagging a sustained rise in chikungunya across multiple countries in the Americas since late 2025, including the return of local transmission in areas that had not seen the virus circulating for years. In 2025, 18 countries in the Americas reported more than 315,000 chikungunya cases.
Costa Rica's own numbers remain small in that context. Twenty-one cases nationally is not an epidemic, and framing it as one would misrepresent the notice.
Who Faces the Greatest Risk
Travelers staying in accommodations without air conditioning or intact window screens face the most exposure, since Aedes mosquitoes bite primarily during daylight hours and breed in small amounts of standing water close to where people sleep.
Older travelers, people with diabetes or heart disease, pregnant travelers, and families traveling with newborns are the groups for whom infection carries the most consequence.
Aedes mosquitoes are daytime biters, which catches people out. A traveler who applies repellent only at dusk, on the assumption that mosquitoes are an evening problem, is unprotected during exactly the hours spent at the beach and pool.
What to Do Before and During the Trip
Use an EPA-registered insect repellent containing DEET, picaridin or IR3535, and follow the label. If you are also using sunscreen, apply sunscreen first and repellent second.
Wear long-sleeved shirts and long pants where the heat allows, and choose accommodations with air conditioning or screens on windows and doors. Around a hotel or rental, tip out anything holding standing water, including buckets, plant saucers and uncovered containers.
Treating clothing and gear with permethrin before travel adds a layer that does not wash off with sweat.
What to Do If You Get Sick
Seek medical care if you develop fever, joint pain, headache, muscle pain, joint swelling or rash during travel or after returning home.
The detail that changes what a clinician tests for is the travel history. Tell them specifically that you were in Guanacaste and when. A U.S. emergency department will not consider chikungunya unless prompted, and the symptoms overlap with more familiar illnesses.
Anyone who becomes ill during the first week of a trip should also take extra care to avoid further mosquito bites, since a person carrying the virus can pass it to local mosquitoes and extend the outbreak.
Cost and Access
Travel vaccines and travel medicine consultations are frequently not covered by standard insurance, and costs vary considerably. Ask about coverage before the appointment rather than after.
County health departments in many areas operate travel clinics at lower cost than private ones. Anyone with a trip inside the next few weeks should book quickly, since some travel vaccines require lead time to take effect.
What Happens Next
CDC updates travel health notices as outbreak conditions change, and a notice can be raised, lowered or removed. Costa Rica's Ministry of Health is continuing case investigation and vector control in the Santa Cruz area. Whether the outbreak stays confined to Playa Langosta or extends along the Guanacaste coast is the open question. MedicalDaily will report changes to the notice level or case counts.
The Bottom Line
The confirmed facts are a CDC Level 2 notice for Guanacaste Province, confirmed local transmission near Playa Langosta, and 21 national cases as of late July. The travelers most affected are those with Tamarindo-area trips booked in the coming weeks, particularly pregnant travelers and adults over 65. The concrete steps are a clinician conversation about vaccination, daytime repellent use, and screened or air-conditioned lodging. The central uncertainty is whether transmission spreads beyond the current area.
