Puerto Rico declares public health emergency as dengue cases surge

Puerto Rico has declared a public health emergency due to a surging number of dengue cases.

Puerto Rico Secretary of Heath Carlos Mellado said the health department has registered 549 cases of dengue so far this year, far exceeding historical numbers.

“Our teams have been working on an integrated plan for prevention and control in response to arboviruses and we are going to expand the response implemented,” Mellado said in a statement, noting that the declaration will allow additional resources that can strengthen surveillance and case management programs.

Dengue is the most common mosquito-borne virus worldwide. More than 400 million people are infected every year. It spreads mainly via the Aedes aegypti mosquito, which is also known to carry several other viruses such as yellow fever, chikungunya and Zika.

The virus is endemic in more than 100 countries in tropical and subtropical climates, mostly in urban and semi-urban areas, according to the World Health Organization — and in the US territories of Puerto Rico, the US Virgin Islands and American Samoa.

About 1 in 4 people infected with dengue will have symptoms, including fever, nausea, vomiting, rash and body aches — typically muscle, joint or bone pain or behind the eyes.

Severe dengue is less common, but the symptoms can include shock and internal bleeding. About 40,000 people die from severe dengue around the world each year, according to the US Centers for Disease Control and Prevention.

Health officials in Puerto Rico are urging people to use insect repellent and eliminate possible mosquito breeding sites by preventing water from accumulating.

“It is also essential to wear clothing that covers exposed skin and consider installing mosquito nets on beds and wire mesh on doors and windows,” Mellado said.

In the US, there is a dengue vaccine for children ages 9 to 16 who have laboratory-confirmed evidence of a previous dengue infection and who live in areas where dengue is endemic, including Puerto Rico. There is no dengue vaccine available for adults in the US.

Dengue outbreaks occur occasionally in the continental United States; last year, several cases were reported in Florida. But most cases are reported in Puerto Rico, Dr. Gabriela Paz-Bailey, chief of the Dengue Branch in the Division of Vector-Borne Diseases at the DCC, told CNN last year.

“It has the perfect climate for it. It’s a tropical island,” Paz-Bailey said. “There are indeed efforts from the health department and other organizations like the Puerto Rico vector control unit to control dengue in the area.”

Climate change will also encourage the spread of dengue around the world, Paz-Bailey said.

“Higher temperatures will probably expand the range of places where a mosquito can survive,” she said. “And then it can also facilitate transmission through other ways, like faster viral replication in the mosquito and increased survival of mosquitoes.”

CNN’s Jamie Gumbrecht contributed to this report.

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