Effect of a conjugate pneumococcal vaccine on the occurrence of respiratory infections and antibiotic use in day-care center attendees

Background. Incidence and severity of respiratory infections are increased in day-care center attendees. Streptococcus pneumoniae is an important cont ributor to these infections. Objective. To examine whether the use of a pneumococcal conjugate vaccine c ould reduce the occurrence of respiratory infections and the ensuing antibi otic drug use in the day care. Method. In this double blind, randomized, controlled study performed in 8 d ay-care centers located in Beer-Sheva, Israel, 264 toddlers ages 12 to 35 m onths at enrollment were randomized to receive either a 9-valent conjugate pneumococcal vaccine (conjugated to CRM197) or a control vaccine [conjugate meningococcus C vaccine (conjugated to CRM197)] and were followed for an a verage of 22 months. The main outcome measures were respiratory morbidity a nd antibiotic use. Results. An overall reduction of 7% in child months with greater than or eq ual to1 reported illness episodes was observed among vaccinees (P = 0.008), and 85% of all episodes were related to the respiratory tract. Reductions of 15, 16 and 17% were observed in upper respiratory infections, lower resp iratory problems and otitis media, respectively. An overall reduction of 17 % in antibiotic days was observed [10% for upper respiratory infections, 20 % for otitis and 47% for lower respiratory problems (P less than or equal t o 0.005 for each entity)]. The reduction in episodes and antibiotic use was greater for those < 36 months of age than for the older children. Conclusion. The reduction of respiratory problems, including those not trad itionally considered of pneumococcal origin and the ensuing lowered antibio tic use in day-care center attendees by pneumococcal conjugate vaccination suggest a broader benefit from the vaccine than preventing invasive disease only.