Prevalence and antimicrobial patterns of Acinetobacter baumannii on hands and nares of hospital personnel and patients: The iceberg phenomenon again

OBJECTIVE: To determine the prevalence and antimicrobial susceptibility patterns of Acinetobacter baumannii on the hands and nares of health care workers and patients from intensive care and rehabilitation units at two hospitals in northern Manhattan, New York. DESIGN: Prevalence survey of Acinetobacter on the hands and anterior nares of staff (n = 184) and patients (n = 98) in rehabilitation and intensive care units of two hospitals. RESULTS: Twenty subjects (7.1%) had positive test results for A baumannii (6 staff [3.3%] and 14 patients [14.3%]). Five patients had positive test results at both sites, four in the nares only, and 11 on hands only. Among patients, four significant predictors of A baumannii were days on unit (P = .003), location (hospital A or B) (P = .01), surgery (P = .04), and receiving an antifungal agent (P = .02; OR, 5.6; 95% CI, 1.25-24.52). Among staff, predictors were skin damage (P = .02) and employment in hospital B (P = .03). Nine of the 20 subjects (45%) had positive test results for multiresistant strains, one from a staff member and eight from patients. CONCLUSION: Patients whose conditions are not clinically symptomatic for A baumannii, as well as staff, are often colonized. Staff with damaged skin are more likely to be colonized. Control of this organism will only be possible when the principle of the iceberg phenomenon - all patients (and staff) treated with standard, Universal Precautions - is strictly followed. Further, the endemic prevalence of multiresistant strains may be higher than previously appreciated.