Prevention of invasive pneumococcal disease among HIV-infected adults in the era of childhood pneumococcal immunization

Abstract

Human immunodeficiency virus (HIV) infection and AIDS increase the risk of invasive pneumococcal disease (IPD). We evaluated IPD among HIV-infected adults over a 10-year period in the US to identify opportunities for prevention of IPD among HIV-infected adults. IPD and HIV surveillance in seven population-based and laboratory-based Active Bacterial Core surveillance areas. IPD cases were adults 18-64 years old with pneumococcus isolated from a normally sterile site during 1998-2007. Isolates were serotyped using the Quellung reaction. HIV/AIDS status was determined by medical record review. We calculated incidence of IPD among adults with AIDS using national case-based surveillance data. Of 13 812 IPD cases among 18-64-year-olds, 3236 (23%) occurred among HIV-infected adults (with or without AIDS) and 1313 (10%) occurred among the subset of HIV-infected adults with AIDS. Compared with the period (1998-1999) before childhood 7-valent pneumococcal conjugate vaccine (PCV7) introduction in the US, the overall incidence of IPD among adults with AIDS decreased 25% from 399 to 298 cases per 100 000 by 2007 (P = 0.008). In 2006-2007, 8, 39 and 55% of IPD cases among adults with AIDS were caused by serotypes included in the 7-valent PCV, 13-valent PCV and 23-valent pneumococcal polysaccharide vaccines, respectively. Sustained declines in IPD have occurred among adults with AIDS in the US, but incidence remained high 7 years after PCV7 introduction. More aggressive efforts, including HIV-prevention measures and the use of new PCVs in children and possibly HIV-infected adults, are necessary to further reduce IPD among HIV-infected adults.