Influence of host genetics and environment on nasal carriage of staphylococcus aureus in danish middle-aged and elderly twins.

Journal Article


Nasal carriage is a major risk factor for Staphylococcus aureus infection. Approximately, one-quarter of adults carry S. aureus. However, the role of host genetics on S. aureus nasal carriage is unknown.


Nasal swabs were obtained from a national cohort of middle-aged and elderly Danish twins. Subjects colonized with S. aureus were identified by growth on selective plates and spa typing. A second sample was obtained from twins initially concordant for carriage. Twins found to again be colonized with S. aureus were defined as persistent carriers.


The prevalence of S. aureus carriage among 617 twin pairs (monozygotic/dizygotic pairs: 112/505) was 26.3% (95% confidence interval [CI], 24.0%-28.9%). The concordance rate for carriage did not differ significantly between pairs of monozygotic (37.5%; 95% CI, 22.3%-53.8%) twins and same sex (24.2%; 95% CI, 15.4%-34.5%), and opposite sex (21.4%; 95% CI, 12.0%-33.4%) dizygotic twins. Despite shared childhoods, only 1 of 617 pairs was concordant with respect to lineage. Although heritability increased for S. aureus and lineage persistency, no significant heritability was detected.


In this study, host genetic factors exhibited only a modest influence on the S. aureus carrier state of middle-aged and elderly individuals.

Full Text

Duke Authors

Cited Authors

  • Andersen, PS; Pedersen, JK; Fode, P; Skov, RL; Fowler, VG; Stegger, M; Christensen, K

Published Date

  • October 2012

Published In

Volume / Issue

  • 206 / 8

Start / End Page

  • 1178 - 1184

PubMed ID

  • 22872733

Pubmed Central ID

  • 22872733

Electronic International Standard Serial Number (EISSN)

  • 1537-6613

International Standard Serial Number (ISSN)

  • 0022-1899

Digital Object Identifier (DOI)

  • 10.1093/infdis/jis491


  • eng