Assessment of multi-serotype nasopharyngeal carriage of Streptococcus pneumoniae in infants (6-30 months) in Belgium: taking hidden carriage of pathogenic serotypes into account.

General use of vaccines against Streptococcus pneumoniae (S. pneumoniae) in infants has led to a decrease in the presence of the serotypes against which the vaccine was developed. More than 90 different serotypes of this bacterium exist, of whom the 10 to 13 most pathogenic ones are covered by the current vaccines. As early as the first months of our lives S. pneumoniae is present in the nasal cavity and in the pharynx, mostly temporary and innocuous, yet in some cases, it may lead to infections such as otitis, pneumonia or meningitis. In order to gain a clear understanding of the S. pneumoniae serotypes carried by infants, and the impact of the vaccine used in the vaccination program, a carriage study was set up that is running 3 years from 2016 onward. The carriage study focuses on infants between the age of 6 and 30 months since the presence of S. pneumoniae is more abundant at this age. Swabs are taken from their nasal cavity to investigate presence and dominant type of S. pneumoniae carriage. To detect and monitor hidden carriage of vaccine serotypes or other pathogenic serotypes that can be present next to the dominant serotype, additional laboratory testing will be performed on a subsample of the collected swabs in the first and third year (245 each). The findings of this study will be extremely valuable to enhance insight in transmission of S pneumoniae and to guide decisions on vaccine development, vaccine program, and recommendations on antibiotic treatment.

Keywords:VACCINES, CULTURE, MOLECULAR ANALYSIS

Disciplines:Public health care, Public health sciences, Public health services