Colombia's Yellow Fever Outbreak Threatens Urban Centers

The ongoing outbreak of Yellow Fever in the Republic of Colombia has been progressively expanding in South America, particularly in regions such as the Amazon basin, the Magdalena River, and departments like Meta.

Furthermore, Yellow Fever (YF) outbreaks have been reported in areas where the disease had not historically occurred, including the municipality of Neira in Caldas, which is situated in the coffee-growing region.

Since September 2024, 75 YF cases and 34 deaths have been confirmed in Colombia, representing a fatality rate of 45%.

In 2025, YF cases are distributed in nine departments: Tolima (59 cases), Putumayo (7), Nariño (2), Caquetá (2), Huila, Vaupés, Cauca, Meta, and Caldas (1).

The total number of confirmed YF-related deaths in Tolima is 23.

"A new case has arrived in the municipality of Chaparral, and here we know we have a focus in the east, south, and north, but we have the solution at our fingertips, and that is vaccination," said Health Secretary Katherine Rengifo Hernández, in a media release on April 15, 2025.

"There are educational checkpoints in place, accompanied by law enforcement, following the directives of our governor."

Although urban transmission of yellow fever has not been reported in Colombia since 1929, there is a potential risk of re-emergence.

Urban areas located below 2,200 meters are at risk of being affected by virus-transmitting mosquitoes. However, with climate change, the range of mosquitoes is expanding.

For example, Bogotá, the Distrito Capital, has approximately 8 million residents and is located at an elevation of just 2,640 meters.

To alert residents and visitors, Columbia's National Government declared a YF public health emergency on April 17, 2025. The measure aims to protect the population's lives, contain the spread of the virus, and mitigate its potential impact on public health.

The Government's urgent call to citizens to get vaccinated against yellow fever was reiterated.

Since September 2024, the National Government has intensified its vaccination strategy. The age range for immunization has been expanded, starting at 9 months of age and including people over 59 years of age, with mass mobilizations in the affected municipalities.

And Health Promotion Entities were instructed to form and operate vaccination teams in coordination with the public and private networks in all affected territories.

According to the U.S. Centers for Disease Control and Prevention (CDC), yellow fever is a viral disease transmitted by the bite of infected mosquitoes. In the first 24 hours, symptoms such as fever, headache, and malaise may manifest. In the following 72 hours, symptoms often intensify with gastrointestinal symptoms such as vomiting, diarrhea, and abdominal pain.

Starting on the fifth day, signs such as jaundice (yellowing of the skin and eyes) and bleeding may appear, which can lead to death in unvaccinated individuals.

To alert the millions of international travelers who visit South America each year, the CDC issued a Level 2 Travel Health Advisory on April 15, 2025, highlighting areas in Bolivia, Brazil, Colombia, and Peru.

The CDC stated that travelers to these areas should get vaccinated at least ten days before traveling abroad.

As of April 19, 2025, the YF-VAX (Stamaril) vaccine is commercially available at travel clinics and pharmacies in the United States. And vaccination certificates, for entry into designated countries, are issued upon completion.