A prolonged outbreak of Pseudomonas aeruginosa in A neonatal intensive care unit : Did staff fingernails play A role in disease transmission ?

• Published in: Infection control and hospital epidemiology 2000-02, Vol.21 (2), p.80-85
• Main Authors: MOOLENAAR, R. L, CRUTCHER, J. M, SAN JOAQUIN, V. H, SEWELL, L. V, HUTWAGNER, L. C, CARSON, L. A, ROBISON, D. A, SMITHEE, L. M. K, JARVIS, W. R
• Format: Article
• Language: English
• Subjects: Bacterial diseases; Biological and medical sciences; Colonization; Cross Infection - epidemiology; Cross Infection - microbiology; Cross Infection - transmission; Disease Outbreaks - statistics & numerical data; Disease transmission; DNA, Bacterial - analysis; DNA, Bacterial - genetics; Environmental surveys; Equipment Contamination - statistics & numerical data; Female; General aspects; Genotype; Humans; Infant, Newborn; Infection Control; Infectious Disease Transmission, Professional-to-Patient - statistics & numerical data; Infectious diseases; intensive care units; Intensive Care Units, Neonatal - manpower; Intensive Care Units, Neonatal - statistics & numerical data; Intubation, Intratracheal - adverse effects; Intubation, Intratracheal - instrumentation; Logistic Models; Male; Medical personnel; Medical sciences; Miscellaneous; Nails - microbiology; Neonates; nurses; Nursing; Nursing Staff, Hospital - statistics & numerical data; Oklahoma - epidemiology; Outbreaks; Prevention and actions; Pseudomonas aeruginosa; Pseudomonas aeruginosa - classification; Pseudomonas aeruginosa - genetics; Pseudomonas Infections - epidemiology; Pseudomonas Infections - microbiology; Pseudomonas Infections - transmission; Public health. Hygiene; Public health. Hygiene-occupational medicine; Regression analysis; Retrospective Studies; Risk Factors; Serotyping
• ISSN: 0899-823X; 1559-6834
• DOI: 10.1086/501739

To describe an outbreak of Pseudomonas aeruginosa bloodstream infection (BSI) and endotracheal tube (ETT) colonization in a neonatal intensive care unit (NICU), determine risk factors for infection, and make preventive recommendations. A 15-month cohort study followed by a case-control study with an environmental survey and molecular typing of available isolates using pulsed-field gel electrophoresis. Neonates in the NICU of a university-affiliated children's hospital. Improved hand washing and restriction of use of long or artificial fingernails. Of 439 neonates admitted during the study period, 46 (10.5%) acquired P aeruginosa; 16 (35%) of those died. Fifteen (75%) of 20 patients for whom isolates were genotyped had genotype A, and 3 (15%) had genotype B. Of 104 healthcare workers (HCWs) from whom hand cultures were obtained, P aeruginosa was isolated from three nurses. Cultures from nurses A-1 and A-2 grew genotype A, and cultures from nurse B grew genotype B. Nurse A-1 had long natural fingernails, nurse B had long artificial fingernails, and nurse A-2 had short natural fingernails. On multivariate logistic regression analysis, exposure to nurse A-1 and exposure to nurse B were each independently associated with acquiring a BSI or ETT colonization with P aeruginosa, but other variables, including exposure to nurse A-2, were not. Epidemiological evidence demonstrated an association between acquiring P aeruginosa and exposure to two nurses. Genetic and environmental evidence supported that association and suggested, but did not prove, a possible role for long or artificial fingernails in the colonization of HCWs' hands with P aeruginosa. Requiring short natural fingernails in NICUs is a reasonable policy that might reduce the incidence of hospital-acquired infections.