696. Evaluation of Dirt in Iraq for the Presence of Multidrug-resistant Bacteria Linked to Wound Infections in Combat Casualties
Session: Poster Abstract Session: Skin, Soft Tissue and Joint Infections
Friday, October 21, 2011
Room: Poster Hall B1
Background: Multidrug-resistant (MDR) bacteria have complicated the care of the wounded from Iraq and Afghanistan. Potential sources of these MDR pathogens include inoculation of the wound at the time of injury with dirt from the environment versus nosocomial transmission or colonization of the casualty prior to injury. We screened locations across Iraq for the presence of MDR pathogens in superficial and deep soil samples.

Methods: Soil samples were collected from 3 locations in central and southern Iraq (Baghdad (Sather), Tallil and Basrah) during the months of June (3 locations on Sather Air Base) and September 2010 (6 locations at Sather, 3 locations at Tallil, and 3 locations at Basrah).  3 samples were taken at each location: 1 from the surface, 1 from six inches below the surface and 1 from one foot below the surface.  Soil was added to a 15 mL conical tube and mixed with an equal volume of thioglycolate broth.  Each sample was vortexed and allowed to settle before a 50 μL aliquot was plated on a MacConkey agar plate and incubated at 35°C for 24-48 hours.  Recovered bacterial colonies were restreaked on SBA plates and subsequently identified using the MicroScan AutoSCAN 4 instrument (NBPC30 - Gram Negative Panels). In addition, single surface and 1 foot samples were obtained (1 g of dirt in 9 ml of sterile saline with serial dilutions on MacConkey plates) in June 2009 from Baghdad (downtown) and Mosul and Tikrit,  both from northern Iraq, in an assessment for only Acinetobacter baumannii.

Results: Pan-susceptible Acinetobacter lwoffii colonies were recovered from the sub-surface soil samples collected from one location in Baghdad during June 2010 and from sub-surface soil samples collected from two locations in Baghdad during September 2010.   No organisms were isolated from soil samples collected from Tallil and Basrah. The samples from 2009 from Baghdad, Mosul and Tikrit revealed no A. baumannii but did include several species of Ralstonia and Pseudomonas.

Conclusion: The lack of significant pathogens in the dirt from various locations across Iraq makes environmental inoculation of the wound at the time of injury the source of MDR bacteria unlikely. This lends greater evidence for the role of nosocomial transmission as the etiology of A. baumannii and other MDR bacteria.

Subject Category: N. Hospital-acquired and surgical infections, infection control, and health outcomes including general public health and health services research

Edward Keen, PhD1, Wade Aldous, PhD2, Joel Rose, BS2 and Clinton K. Murray, MD1, (1)San Antonio Military Medical Center, Fort Sam Houston, TX, (2)AMEDD Center and School, Fort Sam Houston, TX


E. Keen, None

W. Aldous, None

J. Rose, None

C. K. Murray, None

Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.