Frequency of recovery of pathogens from the nasopharynx of children with acute maxillary sinusitis before and after the introduction of vaccination with the 7-valent pneumococcal vaccine

Abstract

To compare the proportion of recovery of pathogens in the nasopharynx of children with acute maxillary sinusitis in the 5 years period before to the 5 years period following the introduction of vaccination with the 7-valent pneumococcal vaccine (PCV7). Nasopharyngeal cultures were obtained from 428 children with acute maxillary sinusitis, 208 between 1996 and 2000, and 220 between 2001 and 2005. The PCV7 was administered to 174 (79%) of the 220 children seen between 2001 and 2005. One hundred and thirty eight potentially pathogenic organisms were isolated from 208 children between 1996 and 2000. Organisms were isolated in 114 patients (55%). The predominant organisms were Streptococcus pneumoniae (59 or 43% of all isolates), Haemophilus influenzae non-type b (46 or 33%), Moraxella catarrhalis (18 or 13%), Streptococcus pyogenes (9 or 7%), and Staphylococcus aureus (6 or 4%). One hundred and sixty five potentially pathogenic organisms were isolated from 220 patients between 2001 and 2005. Organisms were isolated in 121 patients (55%). The predominant organisms were H. influenzae non-type b (68 or 41% of all isolates), Streptococcus pneumoniae (41 or 25%), M. catarrhalis (23 or 14%), Streptococcus pyogenes (20 or 12%), and Staphylococcus aureus (13 or 8%). Significant statistical differences were noted in the rates of recovery of Streptococcus pneumoniae (p<0.05). A decrease occurred in the recovery of Streptococcus pneumoniae resistant to penicillin from 44% between 1997 and 2000 to 27% between 2000 and 2005. An increase was noted in the isolation of beta-lactamase producing H. influenzae from 37% between 1997 and 2000 to 44%. However, neither of these changes was statistically significant. This data illustrates that a significant shift occurred in the causative pathogens of acute maxillary sinusitis in children in the 5 years after the introduction of vaccination of children with the PCV7 as compared to the previous 5 years. While the proportion of Streptococcus pneumoniae declined by 18%, the proportion of H. influenzae increased by 8%.