Brazil's #dengue vaccine, designed to protect against all 4 strains, works safely against at least 2 of them for 5 years www.nature.com/articles/s41...
Long-term efficacy and safety ...
Long-term efficacy and safety ...

Long-term efficacy and safety of the single-dose tetravalent Butantan dengue vaccine - Nature Medicine
This 5-year follow-up of the double-blinded, placebo-controlled phase 3 DEN-03-IB trial evaluating the efficacy and safety of the Butantan dengue vaccine in participants aged 2–59 years in Brazil found that a single dose of the vaccine was effective against DENV-1 and DENV-2, regardless of serostatus at baseline, and was safe.
