Yellow fever is a viral illness caused by the yellow fever virus (ARN Flaviviridae), transmitted through the bite of an infected mosquito. Common symptoms include fever, chills, loss of appetite, nausea, muscle pain, particularly in the back and headaches.

While most individuals recover within five days, severe cases can lead to abdominal pain, liver damage, jaundice, increased bleeding risk, and kidney complications.

In May, health authorities mandated that all travelers departing Costa Rica for Colombia, including residents and tourists, must present proof of yellow fever vaccination. Travelers are required to receive the vaccine at least 10 days before their departure, making it a mandatory condition for exiting the country.

This month’s campaign includes 1,750 vaccine doses, which will be administered at the National Stadium in San José from July 4 to July 24.

Eligible recipients are those traveling to Colombia in July with confirmed airline tickets.

Appointments are required and must be scheduled through the Ministry of Health’s website. Applicants will need to complete a form and select a preferred date. If the website is busy or temporarily unavailable, it’s due to the high volume of requests. Those seeking a yellow fever vaccine appointment are encouraged to keep checking the site regularly, as new time slots may open up.

As of Thursday, July 3, Costa Rica has reported no confirmed cases of yellow fever.

According to the Pan American Health Organization (PAHO), a Rapid Risk Assessment issued in May warned that the public health risk remains high due to continued human infections in endemic countries across the Americas.

So far in 2025, confirmed yellow fever cases have increased eightfold compared to the same period in 2024, attributed to the periodic reactivation of sylvatic (jungle) transmission cycles, with spillover cases affecting humans, said PAHO in its statement.

A total of 235 human cases and 96 deaths have been reported in 2025. By comparison, 2024 saw 61 confirmed cases and 30 deaths. Most of the reported cases in 2025 have occurred in Bolivia, Brazil, Colombia, Ecuador, and Peru.

The Ministry of Public Health oversees both public and private healthcare systems and is responsible for implementing and enforcing health regulations.

---------------
Have you heard of any expatriates in Costa Rica being infected with yellow fever?  We would like to know your thoughts on this story. Send your comments to news@amcostarica.com