Brazil’s record dengue surge: why a vaccine campaign is unlikely to stop it

Mariana Lenharo,  Nature,  2024.

An explosive rise in dengue cases in Brazil has health authorities on edge. In the first two months of 2024, the country registered more than one million cases of the mosquito-borne disease. That’s a record for this period — and Brazil’s dengue cases normally peak between March and May (see ‘Dengue’s early surge in Brazil’). Factors such as climate change and rapid urban growth are fuelling the surge, which has already killed at least 214 people this year. In response to the crisis, Brazil has become the first country to roll out a public vaccination campaign against dengue.

The campaign is an important addition to the fight against dengue, scientists say. But they warn that the effort is too modest to solve the immediate crisis. “Very few people are being vaccinated. To have an impact on the rates, we would need to have mass vaccination,” says Ana Lúcia de Oliveira, an infectious-disease specialist at the Federal University of Mato Grosso do Sul in Campo Grande, Brazil. And even widespread vaccination won’t defeat the disease unless basic sanitation problems are addressed, researchers note.

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