Brazil halts Butantan dengue vaccine following severe adverse events

The Brazilian Ministry of Health announced a temporary suspension of the dengue vaccine developed by Instituto Butantan after 42 reports of severe adverse reactions, three hospitalisations and two deaths that are under investigation for a causal link. More than 501,000 people had received the vaccine since its introduction in January, including pilot groups in Botucatu (SP), Maranguape (CE), Nova Lima (MG) and health workers nationwide. Vaccinated individuals are advised to watch for dengue‑like symptoms such as fever, persistent vomiting, bleeding or abdominal pain within 21 days of inoculation and seek medical care; those vaccinated earlier than 21 days are considered protected.

In Campo Grande, the municipal health secretariat emphasized that the suspension does not affect the Qdenga vaccine, which is administered to children and adolescents aged 10‑14 and continues to be offered safely. Officials warned against misinformation that could lower vaccination rates. Of the 1,033 health professionals who received the Butantan vaccine, 56 reported only mild reactions like injection‑site pain. The city reports no current dengue deaths or severe cases, with vaccination coverage around 40% for the target adolescent group.