The Inanimate Environment of an Intensive Care Unit as a Potential Source of Nosocomial Bacteria: Evidence for Long Survival of Acinetobacter calcoaceticus

Abstract

Environmental surface and personnel hand impression cultures were obtained during 13 sampling periods in the University of Virginia Pediatric Intensive Care Unit to document potential reservoirs of nosocomial pathogens. In 78 environmental cultures Staphylococcus aureus was found eight times and gram-negative bacilli ten times. The patient chart cover was the most commonly contaminated surface. Acinetobacter calcoaceticus was found in five of ten cultures positive for gram-negative bacilli. Thirty of 59 hand cultures were positive for S aureus and gram-negative bacilli; nurses and residents had both, respiratory therapists only gram-negative bacilli, and A calcoaceticus was the most commonly isolated bacterium of potentially nosocomial significance (14/30). Laboratory investigation of bacterial survival revealed that gram-negative bacilli survived on a dry formica surface from a few hours up to three days but Acinetobacter survived up to 13 days. Since A calcoaceticus has been implicated in many nosocomial infections, its long survival on a dry surface may be an additional factor in its transmission in hospitals and suggests that more attention be paid to environmental surfaces as a source of significant nosocomial pathogens.

Antibiotic use is associated with resistance of environmental organisms in a teaching hospital

“…19,20 Arguably, some epidemiological characteristics of CNS mirror those of S. aureus, including methicillin-resistant S. aureus, which means that patients may well acquire such organisms from contaminated hand-touch sites via staff hands. 5,6 In the current climate, more emphasis on the decontamination of hand-touch sites in clinical areas is required. 21 Breaking the final link in the chain of infection by constant emphasis on hand hygiene remains a challenge for all infection control teams.…”

“…[1][2][3] Dust from a variety of surfaces contains organisms of surprising resilience that may be transmitted to patients by hands. [4][5][6] Hospital organisms also tend to be more resistant to antibiotics. 7 Local patterns of prescribing encourage the selection of resistant organisms in both patients and the hospital environment.…”

Occurrence of an Environmental Acinetobacter baumannii Strain Similar to a Clinical Isolate in Paleosol from Croatia

“…At a relative humidity of 31%, strains of A. baumannii have survived as long as 36 days (33,34). On a dry Formica surface, A. calcoaceticus has survived as long as 13 days (35). Thirty-nine of 118 Acinetobacter sp.…”

Metallo-β-lactamase expressing multi-resistant Acinetobacter baumannii transmitted in the operation area

“…Acinetobacter survives in soap and soap dispensers containing 2% chlorhexidine gluconate 12,13 and also on dry filter paper. 14,15 Transmission of multiresistant A. baumannii strains occurred in a Dutch hospital from patients colonized by multiresistant A. baumannii and methicillin-resistant Staphylococcus aureus (MRSA). Interestingly, ensuring strict isolation procedures prevented spread of MRSA but not of multiresistant A. baumannii.…”