Streptococcus Pneumoniae Nasopharyngeal Carriage

Antibiotic consumption and antimicrobial resistance remain notoriously high in France, particularly among children below three years of age. In France, the pneumococcal conjugate vaccine was officially recommended for all children under two in 2003, and consequently changes occurred in Streptococcus pneumoniae serotype distribution. Bacterial carriage among children attending day-care centres may result from vaccine- and antibiotic-driven selective pressure with possible repercussions on the community.

To identify prevalence (rates) and trends in antibiotic resistance patterns in Streptococcus pneumoniae (SP) among children attending day-care centres, as well as antibiotic prescriptions and vaccine rates, nasopharyngeal (NP) carriage was monitored, by conducting five cross-sectional surveys from January to March 1999, 2002, 2004, 2006 and 2008 among these children in the area of the Alpes Maritimes, in South-Eastern France.

Interventions promoting prudent antibiotic use (PAU) took place in 2000 and since 2003, with temporary effectiveness but national prescription rates are reported to be currently increasing again. A new pneumococcal conjugate vaccine covering more serotypes (13-valent) now replaces the previous one. In this situation, a new cross-sectional survey in day-care centres with the same design may answer the following questions.

• Increasing antibiotic susceptibility was observed during past successive surveys. Has this trend been sustained to this day?
• Are antibiotics prescription rates among children attending day-care centres still decreasing, have they stabilized, or are they on the rise again reflecting recently reported national trends?
• Regarding choice of antimicrobial treatment, are 3rd generation cephalosporin increasingly prescribed rather than aminopenicillins?
• Is implementation of the new wider spectrum pneumococcal conjugate vaccine exerting changes on serotype distribution and thus on the nasopharyngeal ecosystem of these children? These parameters will be useful to renew, or even reinforce, and adapt professional guidelines and community-oriented messages concerning prudent antibiotic use.

Sub-study: Antibiotic-resistant enterobacteriaceae, initially observed in the hospital setting, are currently spreading within the community, especially extended-spectrum beta-lactamase-producing enterobacteriaceae, threatening antibiotic effectiveness in case of infection. Such infections with Enterobacteriaceae, in particular urinary tract infections, can occur among children. Prevalence rates of such carriage among children attending day-care centres is unknown, although they are highly exposed to antibiotics in relation with frequent respiratory tract infections, in particular to 3rd generation cephalosporins. To assess this prevalence rate, faecal samples from children attending day-care centres will be collected during the cross-sectional nasopharyngeal survey quoted above.