Streptococcus pneumoniae in the potential effects of new vaccines on the pattern of antibiotic drug usage in pediatrics

Background: Streptococcus pneumoniae is a common cause of respiratory tract infections and acute otitis media. The main reservoir of S pneumoniae is the nasopharynx. From there, it can spread to cause disease in various foci. Objective: This article reviews studies on the use of vaccines to prevent the spread of S pneumoniae, particularly antibiotic-resistant serotypes. Methods: Published data were identified using a PubMed search of the literature published from 1995 to the present in all languages, using the search terms S pneumoniae, vaccines, and antibiotic resistance. Relevant conference presentations were also included. Results: Most children are colonized during the first years of life. Antibiotic resistance to S pneumoniae is prevalent and increasing, which affects clinical outcomes and antibiotic use. In clinical studies, conjugate pneumococcal vaccines reduced the rates of carriage of those pneumococcal serotypes included in the vaccines. They also appeared to increase the rates of carriage of pneumococcal serotypes not related antigenically to those in the vaccines (a replacement phenomenon). Antibiotic resistance is most prevalent among serotypes included in the conjugate vaccines. Studies have also shown that conjugate pneumococcal vaccines reduced the carriage and spread of antibiotic-resistant S pneumoniae, including among younger siblings of toddlers in day care. The reduction in carriage of antibiotic-resistant S pneumoniae was associated with a reduction in the number of respiratory infections and use of antibiotics in day care centers. Conclusions: Preliminary studies of conjugate pneumococcal vaccines suggest that they may help prevent the spread of antibiotic-resistant serotypes and reduce the need for antibiotic therapy for S pneumoniae infections.