title: Reduction of nasopharyngeal carriage of Streptococcus pneumoniae after administration of a 9-valent pneumococcal conjugate vaccine to toddlers attending day care centers.
abstract: A double-blind, randomized study involving 264 toddlers attending day care centers was conducted to document the effect of a 9-valent pneumococcal conjugate vaccine on the carriage rate of pneumococci. Of 3750 cultures done on nasopharyngeal samples obtained from subjects during a 2-year follow-up period after vaccination, 65% were positive for Streptococcus pneumoniae. In all age windows, the rate of carriage of vaccine-type pneumococci was lower among subjects who received the pneumococcal vaccine than among control subjects, because the acquisition rate was lower in the former group. The effect was most pronounced among subjects aged < or =36 months. The sample size enabled us to study protection against carriage of S. pneumoniae serotypes 6B, 9V, 14, 19F, and 23F; significant protection against all serotypes except 19F was seen in the pneumococcal-vaccine group. The rate of carriage of serotype 6A (not included in the vaccine) was also reduced significantly, but the rate of carriage of serotype 19A (not included in the vaccine) was not. The rate of carriage of non-vaccine-type pneumococci (excluding serotype 6A) was higher in the pneumococcal-vaccine group than in the control group.
authors.affiliation: Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer-Sheva 84101, Israel. rdagan@bgumail.bgu.ac.il
authors.forename: Ron
authors.initials: R
authors.lastname: Dagan
authors.forename: Noga
authors.initials: N
authors.lastname: Givon-Lavi
authors.forename: Orly
authors.initials: O
authors.lastname: Zamir
authors.forename: Merav
authors.initials: M
authors.lastname: Sikuler-Cohen
authors.forename: Lior
authors.initials: L
authors.lastname: Guy
authors.forename: Jacob
authors.initials: J
authors.lastname: Janco
authors.forename: Pablo
authors.initials: P
authors.lastname: Yagupsky
authors.forename: Drora
authors.initials: D
authors.lastname: Fraser
mesh_terms: D002353:Carrier State / Q000382:microbiology / Q000517:prevention & control*; D002656:Child Day Care Centers; D002675:Child, Preschool; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009305:Nasopharynx / Q000382:microbiology*; D011008:Pneumococcal Infections / Q000382:microbiology / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000008:administration & dosage* / Q000276:immunology; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification / Q000276:immunology / Q000302:isolation & purification*; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000276:immunology
chemical_list: D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate