16 residents of Long Island infected with dengue this year, CDC says

More than 140 New Yorkers, including up to 16 from Long Island, have been infected with dengue, a potentially fatal mosquito-borne illness transmitted in tropical parts of the globe, according to data from the federal Centers for Disease Control and Prevention.

None of the New York cases has resulted in a death, according to the state Health Department, and there is no evidence local mosquitoes are infected.

The record-breaking number of dengue cases worldwide this year prompted the CDC last month to issue a travel alert, warning health care providers and public health authorities about an increased risk of infection.

In total, 2,559 people have been reported as infected in the United States this year — roughly five times more than at this point in 2023 — with visitors returning from Puerto Rico representing about 1,700 of those cases. Puerto Rico declared a public health emergency related to dengue in March.

The rise in cases, experts said, is linked to climate change, an increase in international travel and the cyclical nature of the virus. Numbers are expected to rise even further during the July-through-September peak travel season.

All of New York's 143 dengue cases are connected to international travel, while sporadic cases or small localized outbreaks have been reported in Florida, Texas and Hawaii, New York officials said.

“There is currently no evidence for infected local mosquito populations,” said Danielle De Souza, a spokeswoman for the state Health Department.

Since the start of 2024, more than 10 million dengue cases — twice as many as in all of 2023 — and over 5,000 dengue-related deaths have been reported from 80 countries, according to the CDC.

On Long Island, 12 Suffolk residents have tested positive for dengue, the most since 13 cases were reported in 2013, federal data shows.

Grace Kelly-McGovern, spokeswoman for the Suffolk County Health Department, said the dozen infected individuals traveled to countries in the Caribbean, Central America and South America.

“Three were hospitalized and received supportive care,” Kelly-McGovern said. “All recovered.”

Suffolk had eight dengue cases in 2023; four in 2022; and none in either 2021 or 2020, according to Health Department data.

The CDC reported between one and four cases of dengue in Nassau County this year. 

Alyssa Zohrabian, spokeswoman for the Nassau Health Department, declined to specify precisely how many cases were reported or the condition of those individuals, citing “privacy concerns” because of the low numbers of cases.

“Nassau County Department of Health investigates all reported cases of dengue virus in Nassau residents,” Zohrabian said. “Our investigations have revealed that all reported cases involve individuals who traveled to countries where dengue is prevalent, with no evidence of local transmission within Nassau County at this time.”

New York City has reported 95 cases, with 41 in Manhattan, 23 in Brooklyn, 22 in Queens and nine in the Bronx, according to the CDC. In all of 2023, the city reported 169 cases, according to a June 28 City Health Department advisory. 

Dengue virus is transmitted through the bite of an infected Aedes aegypti or Aedes albopictus mosquito, which commonly breeds in Central and South America, Mexico and the Caribbean.

The most common symptoms are a fever with aches and pains, chills, malaise, nausea, vomiting and a rash. Serious cases, medical officials said, can involve bleeding, coagulopathy and liver and organ failure. 

Symptoms typically begin two weeks after being bitten by an infected mosquito and last two to seven days. Most people recover after about a week. 

Dengue is not contagious but can be fatal, particularly for individuals with comorbidities and those who contract the virus more than once, said Dr. Bruce Farber, chief of public health and epidemiology at Northwell Health.

“The first episode of dengue is no fun,” Farber said. “But the second and third episode are what usually kill people.”

North Shore University Hospital in Manhasset has treated five dengue patients this year and 20 last year, Farber said.

There is no specific treatment for dengue. A vaccine for the virus is recommended only for children living in an area where dengue is endemic.

“We're seeing an exponential growth in cases,” said Dr. Andrew Fleming, an infectious disease specialist and clinical assistant professor at NYU Langone Hospital Long Island in Mineola. “But the level of concern locally is low. The risk is if you travel. You have to be aware of this and take precautions to protect yourself against mosquitoes.”

By Robert Brodsky

robert.brodsky@newsday.com@BrodskyRobert

Robert Brodsky is a breaking news reporter who has worked at Newsday since 2011. He is a Queens College and American University alum.