The Ministry of Health (MS) approved on Thursday (21/12) the incorporation of the dengue vaccine into the Unified Health System (SUS). As a result, starting in February, Brazil will be the first of the 34 countries in which Qdenga is approved to apply it on a large scale for free.
The vaccines will begin to be delivered by the pharmaceutical company Takeda to the government in February 2024, but initially only 460,000 doses are planned. The forecast is that deliveries will be staggered until reaching 5 million doses throughout the year.
The vaccine is administered in two doses, that is, in this first year, it will be possible to vaccinate 2.5 million Brazilians. Each dose will cost R$95 to the public coffers.
What is the vaccine and how does it work?
Qdenga is a vaccine made with an attenuated virus. “These vaccines contain disease-causing antigens, but in a weakened version, without the infectious capacity of wild viruses. With this, the body learns to make defenses that fight the virus”, explains immunologist Flávia Bravo, director of the Brazilian Society of Immunizations (SBIm).
Clinical trials carried out with Qdenga showed a 90% reduction in hospitalizations among those vaccinated. The vaccine has already been approved in 34 countries and, since July, has been available in private clinics.
Who can take it?
The dengue virus has four serotypes and Qdenga protects against all of them. However, this is done less efficiently for types 3 and 4, especially if the person has previously had dengue fever.
At a WHO press conference in October, Finnish Hanna Nohynek, head of the Advisory Group of Experts on Immunization (SAGE), spoke about the limits of Qdenga as a vaccine, but celebrated its development as a new frontier in the fight against dengue.
“Its greatest effectiveness is against forms 1 and 2 of the virus and it does not work well in children who have already had the disease. But this is the first vaccine against dengue and will be important in a scenario in which climate change is making the disease more frequent around the world”, he maintained.
Immunologist Flavia Bravo explains that the vaccine is contraindicated for people with a depressed immune system, pregnant women and breastfeeding women.
Who should be the priority audience?
In the best case scenario, only 3 million Brazilians will be immunized via SUS in 2024. The MS will have to define who will be the priority group for receiving it.
The National Immunization Program (PNI) will define the priority target audience by January. The SBIm representative imagines that the distribution will especially respect regional criteria, going to places where the dengue virus is most endemic and causes the most victims.
“Without a doubt, priority will be given to people who become more seriously ill and those at greater risk of dying from dengue, which are people with chronic diseases such as diabetes and hypertension”, says Flavia Bravo.
How many doses will arrive?
5 to 6 million doses of the vaccine will be distributed throughout 2024, especially in the months of May and August. Takeda maintains that it is able to produce vaccines for everyone considered a priority by the MS.
“We are able to produce vaccines for the entire public that will be considered a priority immediately. We will spare no effort to provide and prioritize the vaccine for the Brazilian population”, defended Vivian Kiran Lee, executive director of Takeda in Brazil, the pharmaceutical company that created the Qdenga vaccine.
Death from dengue in Brazil could be a record
Until epidemiological week 48 (02/12), 1,053 deaths caused by dengue were recorded, a number equal to the total recorded during the year 2022, the most lethal ever recorded in the country. There are still 217 deaths from this year under investigation, which is why experts believe that 2023 will be the year with the most deaths from the virus in history.
Phenomena such as frequent heat waves may be related to the increase in cases and deaths. There was also the return of serotype 3, which had disappeared from Brazil 15 years ago.
Dengue symptoms
Dengue is transmitted by the Aedes aegypti mosquito. The infection can be asymptomatic or present more serious forms, which can lead to death. The classic viral form involves symptoms such as muscle weakness, drowsiness, refusal of food and fluids, vomiting and diarrhea.