Nasopharyngeal Colonization With Pneumococci in HIV-Infected Adults Following the Introduction of Pneumococcal Conjugate Vaccine-13 in Children

1. Rodriguez-Barradas MC, et al. Colonization by Streptococcus pneumoniae among human immunodeficiency virus-infected adults. JID. 1997; 175:590-7. 2. Janoff EN, et al. Streptococcus pneumoniae colonization, bacteremia, and immune response among persons with human immunodeficiency virus infection. JID.1993; 167: 49-56. Background: Before widespread use of pneumococcal conjugate vaccine (PCV) in children, 14-20% of HIV-infected adults were colonized with pneumococci. We characterized nasopharyngeal pneumococcal colonization among HIV-infected adults following the introduction of PCV-13. Methods: HIV-infected adults seeking care at the Designated AIDS Center in Syracuse, NY between December 2013 and March 2015 were eligible. Following informed consent, an NP sample was collected, and patient demographics, medical and social history including risk factors for invasive pneumococcal disease (IPD) recorded. Pneumococci were identified from the samples using standard microbiologic techniques. Results: 707 nasopharyngeal samples were collected from 414 HIVinfected adults; 301 (73%) were males. Mean and median ages were 46.3 and 48 years, respectively. 391 (94%) and 42 (10%) were taking anti-retroviral therapy and sulfamethoxazole/trimethoprim prophylaxis, respectively. In addition to HIV infection, 210 (51%) had another co-morbidity placing them at increased risk for IPD. 12 (3%) had received PCV-13 and 220 (53%) had received pneumococcal polysaccharide vaccine-23 as recommended. Pneumococcus was isolated from 18/707 (2.5%) of samples and from 15/414 (3.6%) of patients. Colonization status was not associated with gender, race, co-morbidities, antibiotic use, smoking, alcohol use, intravenous drug use, children in the household, vaccine status, absolute neutrophil count, CD4 count, or viral load, however, colonized adults were more likely to have respiratory symptoms than those who were not colonized (46% vs 27%, p=0.02). Conclusion: Current pneumococcal colonization rates in HIV-infected adults are below historical rates suggesting reduction due to the widespread use of PCV-13. When present, colonization may be associated with respiratory symptoms.