U.S. health authorities are warning the medical community and the public of a sharp increase in dengue fever cases around the world.
This rise is being fueled by climate change and greater mobility across international borders.
Dengue fever, a viral disease transmitted through the bite of infected Aedes mosquitoes, has escalated to unprecedented levels this year. As of the latest updates, numerous countries across the Americas, including Puerto Rico, have declared public health emergencies in response to record-breaking infection rates.
According to the World Health Organization (WHO), the situation has reached a crisis point with 7.9 million cases and 4,000 deaths reported in just the first four months of 2024—surpassing the total figures of 2023.
Although dengue is primarily prevalent in tropical and subtropical climates, it poses an increasing threat to the contiguous United States.
This year, there has been a threefold increase in reported cases compared to the same period last year, mostly among travelers returning from affected regions.
The Centers for Disease Control and Prevention (CDC) has issued an alert advising healthcare providers to recognize symptoms and inquire about recent travel histories to better identify and manage potential cases.
The disease, often called “break-bone fever” due to the severe pain it can cause, leads to symptoms like high fever, headache, and a flu-like condition. While many do not show symptoms, severe cases can result in bleeding, shock, and even death, particularly in those with secondary infections from different dengue virus serotypes.
U.S. health officials are particularly concerned about the adaptive challenges of dengue management, noting that repeated infections can lead to more severe forms of the disease.
Dr. Gabriela Paz-Bailey, chief of the CDC’s dengue branch in Puerto Rico, emphasized the growing prevalence of serotypes 2 and 3, against which there is little immunity in the population.
Compounding the challenge is the limited availability of effective vaccines. The U.S.-approved vaccine, produced by Sanofi Pasteur, is a three-dose regimen that guards against all four types of the dengue virus but is recommended only for children aged 9 to 16 who have had prior infections and reside in endemic regions like Puerto Rico.
The recent decision by Sanofi Pasteur to discontinue the vaccine has sparked additional concerns, although alternative vaccines are in development.
The surge in dengue cases has broader implications for global travel and local economies, particularly in regions heavily reliant on tourism.
Dr. Lulu Bravo, a pediatric tropical diseases expert at the University of the Philippines Manila, described dengue as “a traveler’s nightmare,” noting that outbreaks can deter tourists, impacting local businesses and international travel trends.
As dengue continues to spread, U.S. health officials stress the importance of preventive measures, including mosquito control and public awareness, to mitigate the impact of this potentially deadly disease.