Vaccination as infection control: A pilot study to determine the impact ofStaphylococcus aureusvaccination on nasal carriage

Background There is a critical need for an effectiveStaphylococcus aureusvaccine for the prevention of staphylococcal disease. In this study, we investigated the impact ofS. aureusconjugate vaccine comprised of capsular polysaccharides 5 and 8 (CP5, CP8) on nasal colonization withS. aureus. Methods Healthy adults recruited from one academic medical center to participate in a lot consistency trial of StaphVAX®(S. aureuscapsular polysaccharide 5 and 8 conjugate vaccine) were assessed forS. aureusnasal colonization at two weekly points prior to vaccination and again at six weeks post-vaccination. Serum anti-capsular antibody titers to CP5 and CP8 were obtained prior to vaccination and 42 days post-vaccination and measured by ELISA. Results Thirty of 88 enrolled subjects (34%) hadS. aureusisolated from at least one of the pre-immunization cultures. Of these, 20 were termed persistent carriers due to two positive cultures one week apart; 19 of the 20 were evaluable at Day 42. Baseline anti-CP8 concentrations were higher in persistent carriers of CP8+S. aureus; however, baseline anti-CP5 levels were not significantly higher in individuals persistently colonized with CP5+S. aureus. Statistically significant rises in antibody concentrations were noted after vaccination. At Day 42, 14 of 19 persistent carriers remained colonized; 5 subjects did not have evidence ofS. aureuscolonization. Ten additional subjects were positive forS. aureusat Day 42 who were not persistently colonized at baseline. Serum antibody concentrations were not statistically different between those with persistent carriage vs. those that lost carriage or those with newly acquired carriage. Conclusions Immune responses to vaccine were brisk and comparable in subjects with or without persistent colonization. Despite a substantial rise in anti-CP5 and anti-CP8 antibody concentrations post-vaccination,S. aureusnasal colonization rates did not significantly change.