Document Type


Date of Degree

Spring 2010

Degree Name

PhD (Doctor of Philosophy)

Degree In


First Advisor

Smith, Tara

First Committee Member

Field, R W

Second Committee Member

Torner, Jim

Third Committee Member

Murph, Jody

Fourth Committee Member

Dawson, Jeff


Staphylococcus aureus (S. aureus) is a ubiquitous bacterium that has the potential to cause severe disease in children and adults. Asymptomatic carriage of S. aureus is an important risk factor for developing infection, as well as a key contributor to transmission. Despite the fact that child care workers are at risk of infections, little research has focused on asymptomatic carriage of S. aureus in this occupational group. We collected samples from 110 employees, 81 children, and 214 surfaces at twelve child care facilities, as well as 111 age- and gender-matched adults not employed at child care centers. After adjusting for age, a household contact with a recent influenza-like illness, and a household contact with exposure to cattle, the odds ratio for S. aureus carriage in child care employees was 0.68 (95% CI 0.31 - 1.50, p-value 0.34). The odds of MRSA carriage was 3.09 times higher in child care employees than unexposed adults after adjusting for a history of cigarette smoking (95% CI 1.04 - 9.17, p-value 0.042). Colonization rates of all S. aureus and MRSA in children were 19.8% and 1.23%, respectively. S. aureus and MRSA were isolated from 9.80% and 0.90% of surfaces. Washing children's hands upon arrival had a protective effect among employees (adjusted OR 0.17, 95% CI 0.095 - 0.32, p < 0.0001). Molecular characterization suggested transmission of S. aureus among children, employees, and environmental surfaces. While the overall prevalence of MRSA is low at child care facilities, employees may be at increased risk of carrying this organism.


carriage, child care, colonization, day care, MRSA, Staphylococcus aureus


x, 160 pages


Includes bibliographical references (pages 135-160).


Copyright 2010 Erin Moritz