title: Evaluation of potential environmental contamination sources for the presence of multidrug-resistant bacteria linked to wound infections in combat casualties.
abstract: OBJECTIVE
  To determine whether multidrug-resistant (MDR) gram-negative organisms are present in Afghanistan or Iraq soil samples, contaminate standard deployed hospital or modular operating rooms (ORs), or aerosolize during surgical procedures.
  
  
  METHODS
  Active surveillance.
  
  
  METHODS
  US military hospitals in the United States, Afghanistan, and Iraq.
  
  
  METHODS
  Soil samples were collected from sites throughout Afghanistan and Iraq and analyzed for presence of MDR bacteria. Environmental sampling of selected newly established modular and deployed OR high-touch surfaces and equipment was performed to determine the presence of bacterial contamination. Gram-negative bacteria aerosolization during OR surgical procedures was determined by microbiological analysis of settle plate growth.
  
  
  RESULTS
  Subsurface soil sample isolates recovered in Afghanistan and Iraq included various pansusceptible members of Enterobacteriaceae, Vibrio species, Pseudomonas species, Acinetobacter lwoffii, and coagulase-negative Staphylococcus (CNS). OR contamination studies in Afghanistan revealed 1 surface with a Micrococcus luteus. Newly established US-based modular ORs and the colocated fixed-facility ORs revealed no gram-negative bacterial contamination prior to the opening of the modular OR and 5 weeks later. Bacterial aerosolization during surgery in a deployed fixed hospital revealed a mean gram-negative bacteria colony count of 12.8 colony-forming units (CFU)/dm(2)/h (standard deviation [SD], 17.0) during surgeries and 6.5 CFU/dm(2)/h (SD, 7.5; [Formula: see text]) when the OR was not in use.
  
  
  CONCLUSIONS
  This study demonstrates no significant gram-negative bacilli colonization of modular and fixed-facility ORs or dirt and no significant aerosolization of these bacilli during surgical procedures. These results lend additional support to the role of nosocomial transmission of MDR pathogens or the colonization of the patient themselves prior to injury.
authors.affiliation: San Antonio Military Medical Center, Brooke Army Medical Center, Fort Sam Houston, Texas, USA.
authors.forename: Edward F
authors.initials: EF
authors.lastname: Keen
authors.forename: Katrin
authors.initials: K
authors.lastname: Mende
authors.forename: Heather C
authors.initials: HC
authors.lastname: Yun
authors.forename: Wade K
authors.initials: WK
authors.lastname: Aldous
authors.forename: Timothy E
authors.initials: TE
authors.lastname: Wallum
authors.forename: Charles H
authors.initials: CH
authors.lastname: Guymon
authors.forename: David W
authors.initials: DW
authors.lastname: Cole
authors.forename: Helen K
authors.initials: HK
authors.lastname: Crouch
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Griffith
authors.forename: Bernadette L
authors.initials: BL
authors.lastname: Thompson
authors.forename: Joel T
authors.initials: JT
authors.lastname: Rose
authors.forename: Clinton K
authors.initials: CK
authors.lastname: Murray
mesh_terms: D000336:Aerosols; D000346:Afghanistan; D000391:Air Microbiology; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003428:Cross Infection / Q000209:etiology / Q000517:prevention & control; D024901:Drug Resistance, Multiple, Bacterial; D004866:Equipment Contamination; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000302:isolation & purification*; D006772:Hospitals, Military; D006801:Humans; D017053:Infection Control; D007493:Iraq; D008952:Mobile Health Units; D009873:Operating Rooms; D012988:Soil Microbiology; D013514:Surgical Procedures, Operative; D014481:United States; D014857:Warfare
chemical_list: D000336:Aerosols; D000900:Anti-Bacterial Agents