title: Carriage of Streptococcus pneumoniae in asymptomatic, community-dwelling elderly in the Netherlands.
abstract: Colonization of the upper respiratory tract by Streptococcus pneumoniae is considered prerequisite for pneumococcal disease. Despite high rates of pneumococcal disease in elderly, pneumococcal carriage rates are usually below 5% when detected by the conventional culture method. We assessed pneumococcal carriage in 330 asymptomatic community-dwelling elderly aged 65 years and older. While pneumococci were cultured from 25 (8%) individuals, 65 (20%) elderly were positive for the pneumococcus-specific lytA gene when tested by quantitative-PCR, increasing the overall number of carriers to 75 (22%). Significantly more oropharyngeal samples were pneumococci-positive (18% versus 10%, p<0.001) when tested by the molecular method as compared to nasopharyngeal samples. Our findings indicate that pneumococcal carriage in elderly is higher than previously reported with up to 1 in 5 asymptomatic community-dwelling elderly positive for pneumococcal carriage, when detected by qPCR. The detection of pneumococci by conventional culture alone, greatly underestimates S. pneumoniae colonization in elderly.
authors.affiliation: Department of Pediatric Immunology and Infectious Diseases, Wilhelmina Children's Hospital, University Medical Center Utrecht, The Netherlands; Spaarne Gasthuis Academie, Spaarne Gasthuis, Hoofddorp, The Netherlands; Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, The Netherlands.
authors.forename: Anna M M
authors.initials: AM
authors.lastname: van Deursen
authors.affiliation: Department of Pediatric Immunology and Infectious Diseases, Wilhelmina Children's Hospital, University Medical Center Utrecht, The Netherlands; Spaarne Gasthuis Academie, Spaarne Gasthuis, Hoofddorp, The Netherlands.
authors.forename: Menno R
authors.initials: MR
authors.lastname: van den Bergh
authors.affiliation: Department of Pediatric Immunology and Infectious Diseases, Wilhelmina Children's Hospital, University Medical Center Utrecht, The Netherlands. Electronic address: l.sanders@umcutrecht.nl.
authors.forename: Elisabeth A M
authors.initials: EA
authors.lastname: Sanders
mesh_terms: D000368:Aged; D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology; D017714:Community-Acquired Infections / Q000453:epidemiology* / Q000382:microbiology; D003430:Cross-Sectional Studies; D003955:Diagnostic Tests, Routine / Q000379:methods; D005260:Female; D006801:Humans; D057187:Independent Living; D008297:Male; D009305:Nasopharynx / Q000382:microbiology; D009426:Netherlands / Q000453:epidemiology; D009960:Oropharynx / Q000382:microbiology; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D015995:Prevalence; D013296:Streptococcus pneumoniae / Q000302:isolation & purification*
keywords: Colonization; Elderly; Nasopharynx; PCR; Streptococcus pneumoniae