Asymptomatic carriage of pneumococcus in children under 2 years of age in Libreville: prevalence and associated factors

Background: The morbidity and mortality attributed to pneumococcus are impressive even in the absence of any problem of antibiotic resistance. The objectives of this study were to determine the prevalence of asymptomatic pneumococcal carriage in children aged between 2 months and 2 years in Libreville and to identify the socio-demographic factors associated with carriage. Methods: Cross-sectional, descriptive, and analytical study from September 2019 to February 2020, including infants aged 2 months to 2 years, randomly selected, in 8 health centres in Libreville. We collected sociodemographic data from children and parents. Nasopharyngeal swabs were taken from each child and analyzed in the laboratory of institut de recherche en ecologie tropicale (IRET). Categorical data were expressed as frequencies. Univariate analyses (odd ratio-OR) were performed to measure the relationship between the relevant variables and pneumococcal carriage, followed by a multivariate analysis using logistic regression. The threshold of statistical significance was set at p<0.05 for a two-tailed chi-square test. Results: Of the 434 children included, 51.2% (n=222) were girls, with a mean age of 5.4±3.2 months. Streptococcus pneumoniae was found in 53 children, giving a prevalence of 12.6% (95% CI [9.5-15.6%]). The prevalence was the same for both sexes. Carriage was associated with more than 2 siblings (OR=2.1; p=0.01); an age greater than 6 months (OR=3.6; p=0.001); a child's rank higher than the median (OR=2.3; p=0.006); a mother's low level of education (OR=4.5; p=0.001); a father working in the informal sector (OR=2.4; p=0.01). The mother's level of education was the factor found in the multivariate analysis (p=0.043). Conclusions: The data from this survey encourage the serotyping of strains to guide the vaccination strategy.