Changes in Invasive Pneumococcal Disease among HIV-Infected Adults Living in the Era of Childhood Pneumococcal Immunization

Abstract

Adults infected with HIV have high rates of invasive pneumococcal disease. Introduction of pneumococcal conjugate vaccine for children could affect disease among HIV-infected adults. To compare invasive pneumococcal disease among HIV-infected adults before and after the introduction of a pediatric conjugate vaccine. Active laboratory-based surveillance in an adult population of 10.8 million, including 38,314 living with AIDS. 7 Active Bacterial Core surveillance areas in the United States. All surveillance-area residents 18 to 64 years of age with Streptococcus pneumoniae isolated from a sterile site between 1998 and 2003. Ratio of the number of cases of invasive pneumococcal disease among HIV-infected adults to the estimated number of adults 18 to 64 years of age living with AIDS; serotype-specific subset analyses; and comparison of periods before and after introduction of conjugate vaccine by using exact tests. Of 8582 cases of invasive pneumococcal disease in adults, 2013 (24%) occurred among persons infected with HIV. Between baseline (1998 to 1999) and 2003, the ratio of invasive pneumococcal disease in HIV-infected adults to the number of adults living with AIDS in the surveillance areas decreased from 1127 to 919 cases per 100 000 AIDS population, a reduction of 19% (P = 0.002). Among HIV-infected adults, the ratio for disease caused by pneumococcal serotypes included in the conjugate vaccine decreased 62% (P < 0.001), although the ratio for disease caused by nonvaccine serotypes increased 44% (P < 0.001). Ratios are proxy measures of incidence rates. The denominator of surveillance-area residents living with HIV infection was not available. Introduction of the pediatric conjugate vaccine was associated with an overall decrease in invasive pneumococcal disease among HIV-infected adults, despite increased disease caused by nonvaccine serotypes.