With information from Paula Laboissière to Agência Brasil
Ten years ago, the first version of a pneumococcal conjugate vaccine was approved in Brazil. The following year, the dose, which protects against pictures ranging from simple earaches to severe cases of meningitis and septicemia, began to be distributed in the public and private healthcare network.
Data from the Brazilian Society of Immunizations indicate a reduction of up to 40% in the number of hospitalizations for pneumonia in the country and 70% of cases of pneumococcal meningitis.
“We have had a tremendous impact since the introduction of the vaccine,” said pediatric infectious disease specialist Renato Kfouri, a member of the Technical Advisory Committee of the National Immunization Program of the Ministry of Health.
In an interview with Agência Brasil, he explained that pneumococcus is responsible for non-invasive diseases such as sinusitis and conjunctivitis, but when it invades the bloodstream, it can cause severe pneumonia, pericarditis and even septicemia.
“When we talk about the pneumococcal vaccine, it is not protection against a single disease, such as chicken pox or influenza, but against a range of diseases,” he said. Kfouri noted that there are more than 90 serotypes of the bacterium and that the vaccine is made contemplating some of them.
The first dose in Brazil, approved in 2009, protected against seven serotypes. Currently, the public network offers protection against 10 serotypes and the private network against 13. Doses that include 15 and 20 serotypes are in the development phase.
In practice, the higher the number of serotypes contained in the vaccine, the greater the dose protection spectrum. According to the pediatrician, the selection of serotypes in this specific case uses criteria such as the frequency of infection, the severity of the cases associated with it and resistance to antibiotics.
Pneumococcal vaccines usually include the most frequent serotypes, which cause more severity and are more resistant to treatment. The doses are applied at 2, 4 and 12 months of life.
“Children, in addition to getting sick more often, are the ones who most carry the pneumococcus and transmit it to other age groups. With the vaccine, in addition to being protected, they no longer carry the bacteria in the throat or nose and are no longer transmitting, reducing the cases of bacteria in adults and the elderly. There is, evidently, this indirect effect, which we call herd protection, “he explained.
Otávio Cintra, medical director of vaccines for GSK, the manufacturer of the pneumococcal vaccine used by the Brazilian government, recalls that the process began with a partnership for technology transfer between the laboratory and the Oswaldo Cruz Foundation (Fiocruz).
“Brazil was one of the first countries to introduce, on a large scale, a conjugated vaccine, of the new generation. Until then, we had polysaccharide vaccines, which do not give maintenance, over time, in the production of antibodies, “he said.
“In the conjugate vaccine, the polysaccharide protein becomes a much more potent antigen and can already be used from 2 months of life.
The previous dose could only be used after 2 years and only for people at risk. It did not meet the need, since 80% of pneumococcal infections happen in younger children, “he said.
The estimate is that up to 80% of children under 1 year will have at least one episode of ear infection – of these, about 40% of cases are caused by pneumococcal bacteria.
Since 2010, the National Immunization Program of the Ministry of Health offers the 10-valent pneumococcal vaccine, which protects against 10 serotypes of the bacterium.
The ministry, however, has just authorized the incorporation of a dose that includes 13 serotypes, to be made available exclusively in Special Immunobiological Reference Centers for the following groups: people living with HIV / AIDS; transplanted solid organs or stem cells from the bone marrow; and immunodeficiency due to cancer or immunodepression therapy – all over 5 years of age. Dose acquisitions are in the process of being developed.