Carriage of oropharyngeal bacteria among children in a vulnerable rural population living in a tropical region in São Paulo, Brazil

Abstract

This study aimed to detect the carriage of _Streptococcus pneumoniae_, _Haemophilus influenza_, and _Moraxella catarrhalis_ in the oropharynx and a possible association for airway infections in children of a vulnerable population living in a tropical rural settlement, São Paulo, Brazil. Demographic data were collected through standard questionnaires. Oropharyngeal samples were cultured and examined using the multiplex polymerase chain reaction. The molecular method had higher sensitivity and revealed a high rate of colonization by _S. pneumoniae _and _M. catarrhalis_. _H. influenza_ was not detected, highlighting the strength of Brazil's national immunization program. Low income was reported by 61.4% of participants. Carriage of _S. pneumoniae _was positively associated with being female (_P_=0.004) and being brown color (_P= _0.042). We identified risk factors for respiratory infections and vulnerabilities that may be widely applicable to other rural communities in Brazil and other settings of developing countries.