The Ministry of Public Health (MSP) has announced a free yellow fever vaccination campaign taking place this month.

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

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

In October, health officials confirmed the country’s first case of yellow fever in nearly 70 years. The patient was a 29-year-old U.S. woman who entered Costa Rica after traveling from Peru. She had not been vaccinated.

This month’s campaign includes 1,000 vaccine doses, which will be administered at the National Stadium in San José on Nov. 14 and 24.

Eligible recipients are travelers heading to Colombia between Nov. 15 and Dec. 15 with confirmed airline tickets.

Appointments are required and must be scheduled through the MSP’s website. Applicants must complete a form and select a preferred date. If the site is busy or temporarily unavailable, officials say it’s due to high demand. The ministry encourages travelers to check back frequently, as new appointment slots may open.

Health authorities warn that the vaccine is contraindicated for certain groups, including infants under 6 to 8 months old, people over 60, pregnant or breastfeeding women, those with severe immunosuppression (including symptomatic HIV), and individuals allergic to vaccine components.

In May, the government began requiring all travelers departing Costa Rica for Colombia, including residents and tourists, to show proof of yellow fever vaccination. The vaccine must be administered at least 10 days before departure, making it a mandatory condition for leaving the country.

According to the Ministry, Colombia has reported 113 cases and 47 deaths from yellow fever so far this year.

As of Tuesday, Costa Rica has reported no active cases.

This year, the Pan American Health Organization (PAHO) issued an epidemiological alert for the Americas following a rise in confirmed human cases across several countries and a shift in the disease’s geographic distribution.

The MPS, which oversees Costa Rica’s public and private healthcare systems, is responsible for implementing and enforcing national health regulations.