Data on kids whose guardians declined further study follow-up before conference a study end point had been censored at the date of the last follow-up visit. All testing was two-sided at the 5 percent significance level. To keep the significance level for every cohort at 5 percent, nominal P ideals of 0.0492 and 0.0493 for between-group differences in the HIV-infected and HIV-uninfected cohorts, respectively, were required in the ultimate analysis of the principal end factors. All P values presented had been nominal. Data were analyzed by using SAS software, version 9.1 . Results Features of the Participants A total of 548 HIV-infected and 806 HIV-uninfected infants were enrolled; the majority were signed up for Johannesburg.Serogroups within quadrivalent meningococcal conjugate vaccine or quadrivalent meningococcal polysaccharide vaccine included A, C, W135, and Y; others were considered to be nonvaccine types. Statistical Evaluation We used SAS software, edition 9.1 , for analyses. We calculated the rates of bacterial meningitis for each full year from 1998 through 2007, expressed as the true number of cases per 100,000 population, by using U.S. Census annual people estimates, adjusted for age group and race, for the surveillance sites.S. Inhabitants. Race was categorized as dark, white, or other . For each surveillance age group and site group, cases that race was unknown and cases due to S. N or pneumoniae. Meningitidis infection that serotype or serogroup info was unknown were assigned based on the distributions of cases for which competition or serotype or serogroup, respectively, were known.