How effective is Dengvaxia?

Vaccine efficacy (VE) during clinical trials in multiple countries ranged from 76% to 82%. VE varied by serotype and was highest for DENV-4 (89% point estimate) and lowest for DENV-1 and DENV-2 (67% point estimate). Among study participants ages 9 through 16 years who developed protective antibodies, the vaccine reduced their risk of hospitalization with dengue by 79%, and reduced their risk of severe dengue by 84% over the 5-year follow-up period after vaccination. Studies are ongoing to determine how long protection from hospitalization or severe disease may last, but current evidence show protection lasting at least 6 years after the last dose of vaccine.