The outbreak of dengue fever that has unfolded in Latin America over the past three months is staggering in its scale — a million cases in Brazil in a matter of weeks, a huge spike in Argentina, a state of emergency declared in Peru and now another in Puerto Rico.
It forewarns of a changing landscape for the disease. The mosquitoes that spread dengue thrive in densely populated cities with weak infrastructure, and in warmer and wetter environments — the type of habitat that is expanding quickly with climate change.
More than 3.5 million cases of dengue have been confirmed by governments in Latin America in the first three months of 2024, compared with 4.5 million in all of 2023. There have been more than 1,000 deaths so far this year. The Pan-American Health Organization is warning that this may be the worst year for dengue ever recorded.
The rapidly shifting disease landscape needs new solutions, and researchers in Brazil delivered the lone shred of good news in this story with the recent announcement that a clinical trial of a new dengue vaccine, delivered in a single shot, had provided strong protection against the disease.
There are two existing vaccines for dengue, but one is an expensive two-shot regimen, while the other can be given only to people who have already had a dengue infection.
