Respiratory syncytial virus seasonality in Brazil: implications for the immunisation policy for at-risk populations

Freitas, André Ricardo Ribas; Donalisio, Maria Rita

Some limitations of this study can be indicated, including the fact that the data on the positivity for RSV was obtained from an information system, which is still only partially and heterogeneously covered in various regions of the country. In addition, during the period studied, SIVEP-GRIPE did not include other viruses such as metapneumovirus, bocavirus, enterovirus, and human coronavirus, which may cause similar clinical features. Nonetheless, the analysed data represent all the information available in SIVEP-GRIPE, having a great implication on the public health policies in the country. Another limitation of this study was the low mean positivity found from the tests, which depended on several factors independent of the epidemiological situation, such as the quality of sample collection and transportation, in addition to the sensitivity of the test used. Furthermore, the number of collected samples did not allow using weekly laboratory results or the separate evaluation of the states. However, the hospitalisation data for bronchiolitis and pneumonia due to RSV did not suggest regional discrepancies.