New version of dengue fever hits Florida: ‘unprecedented’ outbreaks

New research shows that a new version of the dengue virus has emerged in Florida. The study found that the state has seen an “unprecedented” number of cases caused by dengue virus serotype 3 in the last two years, including locally acquired cases. The outbreaks remain relatively small and localized, at least for now.

Dengue This is a disease transmitted by mosquitoes. Most initial infections cause no symptoms, but about a quarter develop a flu-like illness, and one in 20 cases can develop serious, life-threatening complications such as internal bleeding and shock. There are four main serotypes of dengue virus, and survival of infection provides immunity only to that specific type. To make matters worse, reinfection with a different type of virus actually increases your risk of developing severe dengue fever.

He Aedes The mosquitoes that spread dengue fever are typically found in tropical areas of the world. But in recent decades, its range has expanded due to the risk of dengue infection. In accordance with World Health OrganizationThe number of reported cases of dengue fever has increased tenfold worldwide since 2000, with more than 5 million cases reported in 2019, and the virus is now endemic in more than 100 countries. The threat of dengue is growing, thanks in large part to climate change, and outbreaks have occurred in new parts of Europe and America in recent years, even in the United States.

The virus is not endemic in the continental United States, and most cases today are found in people who have recently traveled to countries where the virus is routinely found. But in early 2022, Florida health officials began noticing an increase in the number of reported dengue cases, both of which were travel-related. and purchased locally. This trend continued in 2023, with more than 700 cases reported. documented this year. In the report published Recently, in the Morbidity and Mortality Weekly Report, local officials teamed up with the Centers for Disease Control and Prevention (CDC) to characterize and better understand these outbreaks.

Between May 2022 and April 2023, the authors found that there were at least 1,037 cases of dengue in Florida, nearly two-thirds of which were caused by dengue virus serotype 3, or DENV-3. Dengue is endemic in the peripheral territories of Puerto Rico and the US Virgin Islands. , but the vast majority of cases observed in these areas since 2010 have been caused by serotypes 1 and 4. The report’s authors say these latest outbreaks represent “an unprecedented number of travel-associated and locally acquired DENV-3 cases in Florida.”

The majority of dengue cases in Florida continued to be travel-related, with the majority originating in Cuba. It’s no coincidence that Cuba experienced large DENV-3 outbreak beginning in July 2022. Cases of DENV-3 have also recently been reported in other parts of America, such as Brazil and Arizona (including the first known state local cases).

The silver lining seems to be that dengue hasn’t made much headway in Florida this time. The team’s genetic analysis found that DENV-3 cases are linked to very closely related strains, including those transmitted by local mosquitoes, which likely means the virus has not spread widely beyond the initial outbreaks. However, researchers say better surveillance will help prevent dengue from becoming an endemic problem.

“Careful monitoring of DENV activity internationally, as well as increased awareness among health care providers about DENV identification and testing, can strengthen preparedness and response to future introductions into non-DENV non-endemic areas,” they wrote.