Factors Leading to Transmission Risk of Acinetobacter baumannii.

OBJECTIVES

To identify patient and healthcare worker factors associated with transmission risk of Acinetobacter baumannii during patient care.

DESIGN

Prospective cohort study.

SETTING

ICUs at a tertiary care medical center.

PATIENTS

Adult ICU patients known to be infected or colonized with A. baumannii.

MEASUREMENTS AND MAIN RESULTS

Cultures of skin, respiratory tract, and the perianal area were obtained from participants and evaluated for the presence of A. baumannii. Healthcare worker-patient interactions were observed (up to five interactions/patient) and activities were recorded. Healthcare worker hands/gloves were sampled at room exit (prior to hand hygiene or glove removal) and then evaluated for the presence of A. baumannii. Two hundred fifty-four healthcare worker-patient interactions were observed among 52 patients; A. baumannii was identified from healthcare worker hands or gloves in 77 (30%) interactions. In multivariate analysis, multidrug-resistant A. baumannii (odds ratio, 4.78; 95% CI, 2.14-18.45) and specific healthcare worker activities (touching the bed rail [odds ratio, 2.19; 95% CI, 1.00-4.82], performing a wound dressing [odds ratio, 8.35; 95% CI, 2.07-33.63] and interacting with the endotracheal tube or tracheotomy site [odds ratio, 5.15; 95% CI, 2.10-12.60]), were associated with hand/glove contamination.

CONCLUSIONS

Healthcare worker hands/gloves are frequently contaminated with A. baumannii after patient care. Patient-level factors were not associated with an increased transmission risk; however, having multidrug-resistant-A. baumannii and specific healthcare worker activities led to an increased contamination risk. Our findings reveal a potential selective advantage possessed by multidrug-resistant-A. baumannii in this environment and suggest possible areas for future research.