On Monday, government leaders in Puerto Rico declared a dengue epidemic after a spike in cases of the mosquito-borne disease hit the island. From the start of the year through March 10, there were 549 cases, including 341 hospitalizations and 29 severe cases, according to the most recent data provide by the Puerto Rico Department of Health. Cases are concentrated in cities including San Juan, Bayamon, Guaynabo, and Carolina.
Between 2010 and 2020, more than 30,000 dengue cases were reported from four U.S. territories, with Puerto Rico reporting the most. In 2012, Puerto Rico reported 199 deaths, which was the last time the commonwealth declared a dengue epidemic.
Dengue fever poses a significant public health threat in many parts of the world, particularly in regions with high mosquito populations and limited access to health care.
The Centers for Disease Control and Prevention (CDC) said it is working with the Puerto Rico Department of Health and the Puerto Rico Vector Control Unit on surveillance of the virus and on training health providers. The CDC is also involved with cleanup campaigns, using insecticides where appropriate, and in education efforts.
The Puerto Rico Department of Health said it is working to enhance surveillance, laboratory, vector control, and outreach interventions.
Albert Ko, an infectious-disease physician and epidemiologist at the Yale School of Public Health, said the ongoing spike in Puerto Rico is unusual because transmission of the virus in drier months is typically low. He stated, “The fact that it’s happening now is really kind of a heads up, a warning sign for us. … We’re having introductions of the virus by people traveling, and we’re seeing these outbreaks in Puerto Rico that are out of the season, which are really unusual.”
Public health experts say these surges are likely to become more common because of climate change and increased travel, facilitating easier transmission of disease worldwide. They warn that diseases