Detecções de vírus respiratórios e Streptococcus pneumoniae em crianças com pneumonia após a inclusão da vacina pneumocócica 10-valente conjugada no cartão vacinal infantil

Abstract

Pneumonia is responsible for approximately 1.6 million annual deaths in children of age five and below worldwide. A group of virus and bacteria is associated with the etiology of this infection being commonly reported the association between them. As strategy of reducing child mortality from this condition, in 2010 it was incorporated the 10-valent pneumococcal vaccine to the child immunization calendar. The objective of this study is to determine the rate of detection of several respiratory viruses and Streptococcus pneumoniae, including its serotypes, in children with pneumonia after the introduction of the 10-valent pneumococcal vaccine in the child immunization calendar. For this, samples of nasopharyngeal aspirates were analyzed in rapid antigen detection by indirect immunofluorescence for Respiratory Syncytial Virus, adenovirus, Influenza A and B and Parainfluenza 1, 2 and 3. After the isolation of S. pneumoniae, it was used the multiplex PCR for its serotyping. 781 samples were analyzed. The detection of the respiratory viruses and S. pneumoniae ranged during the years 2011, 2012 and 2013, in which, at the end, 441 (56,47%) of the samples were negative for both microorganisms, 199 (25,48%) were positive for at least one virus, being the RSV the most detected, 184 (23,56%) were positive for S. pneumoniae and 43 (5,51%) were positive for coinfection (the simultaneous detection of the pneumococcus and the RSV, 60,47%, was the most frequent). There was a percentage reduction of the detection of pneumococcus over the years studied, with the predominance of vaccinal serotypes (69/54,33%). However, despite the decrease of detection of S. pneumoniae, whether they are present or not in the vaccine, there seems to be a growing number of circulating strains of pneumococcus not included in the vaccine, this fact is more evident in the year 2013. As the profile of prevalent serotypes of S. pneumoniae differs from one region to another and the immunity is serotype-specific, it is necessary a continuous surveillance for the knowledgement of the circulation of serotypes that are not included in the vaccine and to ensure that the future vaccines target the appropriate serotypes.