1378. Evaluating the presence of Clostridium difficile in the household environment and its role in disease transmission, Minnesota, 2011-2012
Session: Poster Abstract Session: Clostridium difficile
Saturday, October 5, 2013
Room: The Moscone Center: Poster Hall C
Background: Although environmental contamination is a major cause of healthcare transmission, its role in the community is less clear. We compared C. difficile environmental contamination between households of cases and households of healthy controls and assessed differences in carriage rates among household members in both groups.

Methods: A case was defined as a surveillance catchment area resident with a positive C. difficile stool specimen and no prior positive test in the past 8 weeks. Control households were selected through random digit dialing. During the household visit occurring 1 to 4 (median 3) weeks after initial stool collection, illness information was collected from cases, household members and pets along with stool samples. Environmental samples were collected from bathroom, kitchen, and other high contact areas. Recovered C. difficileisolates were further characterized and spore concentrations were calculated.

Results: Twenty-five case and 10 control households were enrolled. Twelve cases were positive for C. difficile at the time of home visit, with 4 (33%) reporting diarrhea at collection. Of 532 environmental samples, C. difficile was isolated from 16 (3%) samples, from 7 case and 1 control households (p=0.08). Significantly more bathroom samples yielded C. difficile from case vs. control households [11/151 (7%) vs. 0/63; p=0.04]. Spore concentrations were low ranging from 0.03 to 1.59 CFU/cm2. No significant difference in C. difficile carriage was found between case and control household members [5/45 (11%) vs. 3/32 (9%), respectively; p=1.0]. C. difficilewas isolated from 4/12 (33%) dogs in case households. Isolates from a case, household member, and bathroom in one household were indistinguishable by pulsed-field gel electrophoresis.

Conclusion: C. difficile can be found in case household environments and isolated from household members and pets a median of 3 weeks after diagnosis. However, the risk for secondary infections during index case convalescence appears low; any special environmental precautions should focus on the bathroom. Because household contamination just prior and during case patient diagnosis was not evaluated, the role of household exposures in sporadic community-acquired cases remains unknown.

Stacy Holzbauer, DVM, MPH, DACVPM1, Judith Noble-Wang, PhD2, Fernanda Lessa, MD2, Jessica Cohen, MPH2,3, Alicia Shams, MPH2, Lydia Anderson, BS2, L. Clifford Mcdonald, MD2, Kirk Smith, DVM, PhD4 and Ruth Lynfield, MD5, (1)CDC CEFO Assigned to the Minnesota Department of Health, St. Paul, MN, (2)Centers for Disease Control and Prevention, Atlanta, GA, (3)Atlanta Research and Education Foundation, Atlanta, GA, (4)Minnesota Department of Health, St. Paul, MN, (5)Acute Disease Investigation and Control, Minnesota Department of Health, St. Paul, MN

Disclosures:

S. Holzbauer, None

J. Noble-Wang, None

F. Lessa, None

J. Cohen, None

A. Shams, None

L. Anderson, None

L. C. Mcdonald, None

K. Smith, None

R. Lynfield, None

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