Single-dose Dengue vaccine: How it works and who can take it?

The Health Minister, Alexandre Padilha, stated that the expectation is to start using the ready-made vaccines as early as next month.

The efficacy data presented by the Butantan Institute to receive regulatory approval showed that the new vaccine had an overall efficacy of 74.7%, 91.6% efficacy against severe dengue with warning signs, and 100% efficacy against dengue hospitalizations.

The approval for use was for the age group between 12 and 59 years. The vaccine tested and developed in Brazil had its initial stages conceived by the National Institutes of Health (NIH) in the USA.

During a press conference at the Butantan Institute’s headquarters in São Paulo yesterday, the Health Minister stated that the expectation is to start using the ready-made vaccines as early as next month. Currently, Butantan already has over 1 million doses prepared.

Being a single-dose vaccine, the expectation is that the doses will have greater adherence than the current immunizer available in the country. However, Padilha stated that there are no plans for the international vaccine to be removed from the Brazilian immunization program.

The vaccine currently offered by the Ministry of Health in the Unified Health System (SUS) is QDengue, produced by the pharmaceutical company Takeda. The immunizer requires a two-dose scheme, with a 90-day interval between each.

The decision on who will be the first to receive the vaccine has not been finalized yet. Meetings scheduled for the next few days will determine this. Special attention may be given to those actively combating the disease in the field, considering their elevated exposure to the population in general.

The complexities of the disease and the challenges in defining priority groups for vaccination make this decision more difficult than previous vaccination efforts. The safety and performance of the vaccine, especially in individuals previously infected with dengue, add to the complexity of the decision-making process.

At present, there is no approved vaccine in Brazil for individuals over 60 years old. Butantan is currently evaluating the use of the same vaccine in the 60 to 79 age group. Positive results may lead to an extension of the application to younger age groups as well.