Dataset Information

Dynamics of acquisition and loss of carriage of Staphylococcus aureus strains in the community: the effect of clonal complex.

ABSTRACT: BACKGROUND:Staphylococcus aureus nasal carriage increases infection risk. However, few studies have investigated S. aureus acquisition/loss over >1 year, and fewer still used molecular typing. METHODS:1123 adults attending five Oxfordshire general practices had nasal swabs taken. 571 were re-swabbed after one month then every two months for median two years. All S. aureus isolates were spa-typed. Risk factors were collected from interviews and medical records. RESULTS:32% carried S. aureus at recruitment (<1% MRSA). Rates of spa-type acquisition were similar in participants S. aureus positive (1.4%/month) and negative (1.8%/month, P = 0.13) at recruitment. Rates were faster in those carrying clonal complex (CC)15 (adjusted (a)P = 0.03) or CC8 (including USA300) (aP = 0.001) at recruitment versus other CCs. 157/274 (57%) participants S. aureus positive at recruitment returning ? 12 swabs carried S. aureus consistently, of whom 135 carried the same spa-type. CC22 (including EMRSA-15) was more prevalent in long-term than intermittent spa-type carriers (aP = 0.03). Antibiotics transiently reduced carriage, but no other modifiable risk factors were found. CONCLUSIONS:Both transient and longer-term carriage exist; however, the approximately constant rates of S. aureus gain and loss suggest that 'never' or truly 'persistent' carriage are rare. Long-term carriage varies by strain, offering new explanations for the success of certain S. aureus clones.

SUBMITTER: Miller RR

PROVIDER: S-EPMC4003537 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature

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Dynamics of acquisition and loss of carriage of Staphylococcus aureus strains in the community: the effect of clonal complex.

Miller Ruth R RR Walker A Sarah AS Godwin Heather H Fung Rowena R Votintseva Antonina A Bowden Rory R Mant David D Peto Timothy E A TE Crook Derrick W DW Knox Kyle K

The Journal of infection 20140104 5

<h4>Background</h4>Staphylococcus aureus nasal carriage increases infection risk. However, few studies have investigated S. aureus acquisition/loss over >1 year, and fewer still used molecular typing.<h4>Methods</h4>1123 adults attending five Oxfordshire general practices had nasal swabs taken. 571 were re-swabbed after one month then every two months for median two years. All S. aureus isolates were spa-typed. Risk factors were collected from interviews and medical records.<h4>Results</h4>32% c ...[more]

PMID: 24393651

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Dataset Information

Dynamics of acquisition and loss of carriage of Staphylococcus aureus strains in the community: the effect of clonal complex.

Publications

Dynamics of acquisition and loss of carriage of Staphylococcus aureus strains in the community: the effect of clonal complex.

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