Puerto Rico Declares Epidemic of Potentially Fatal, Mosquito-Borne Dengue Fever

On Monday, Puerto Rico’s Department of Health issued a press release announcing an epidemic of dengue fever. Dengue fever is a mosquito-borne illness which can, in some cases, result in death. Puerto Rico last declared an epidemic of dengue in 2012.

Though cases of dengue fever are relatively common in Puerto Rico, with 1,293 cases reported in 2023, the department’s secretary, Carlos Mellado López, reported that in 2024 “dengue cases have exceeded historical figures." So far this year, 549 cases have been reported in Puerto Rico. More than 340 of those cases have resulted in hospitalization.

Many cases of dengue result in debilitating headaches, fever, vomiting, rashes, and body pains, especially behind one’s eyes. In rare cases, dengue fever can cause “plasma leakage” and death.

"It is essential to recognize the symptoms early,” López warned. “In the presence of any of these symptoms, it is recommended to look for medical attention immediately.”

According to the World Health Organization (via PBS), a total of five million dengue cases were reported last year. 2,000 of those cases were fatal. Nearly 80 percent of all cases were localized to the Western Hemisphere.

Three million cases of dengue have already been reported in the same region throughout 2024. Puerto Rican health officials explained that the uptick in cases is due to higher rainfall as well as increased heat and humidity as a result of climate change.

“Studies show that warmer temperatures associated with climate change can accelerate mosquito development, biting rates, and the incubation of the disease within a mosquito,” explained the Environmental Protection Agency (EPA).

“It is crucial that citizens take immediate and proactive measures to control the spread of the virus and protect themselves and their families,” López advised.

In Puerto Rico, there is a dengue vaccine available for adults 17 and older. Children aged nine to 16 who have previously had the illness and are "living in areas where dengue is endemic" are also eligible to receive the shot.