An Outbreak of Pseudomonas aeruginosa Pneumonia and Bloodstream Infection Associated With Intermittent Otitis Externa in a Healthcare Worker

Abstract

ArstractObjectives:To investigate an outbreak ofPseudomonas aeruginosapneumonia and bloodstream infection among four neonates, determine risk factors for infection, and implement preventive strategies.Design:Retrospective case finding; prospective surveillance cultures of patients, personnel, and environmental sites; molecular typing by pulsed-field gel electrophoresis; and a matched case-control study.Patients and Setting:Neonates in the level-III neonatal intensive care unit of a tertiary-care pediatric institution.Interventions:Cohorting of patients with positive results forP. aeruginosa, work restrictions for staff with positive results, implementation of an alcohol-based hand product, review of infection control policies and procedures, and closure of the unit until completion of the investigation.Results:Seven (4%) of 190 environmental cultures and 5 (3%) of 178 cultures of individual healthcare workers' hands grewP. aeruginosa. All four outbreak isolates and one previous bloodstream isolate were genotypically identical, as were theP. aeruginosaisolates from the hands and external auditory canal of a healthcare worker with intermittent otitis externa. Four of 5 case-patients versus 5 of 15 matched control-patients had been cared for by this healthcare worker (P= .05). The healthcare worker was treated and no further cases occurred.Conclusions:These findings suggest that a healthcare worker with intermittent otitis externa may have caused this cluster of fatalP. aeruginosainfections, adding the external ear to the list of colonized body sites that may serve as a source of potentially pathogenic organisms.

Quarantine, Isolation, and Cohorting: From Cholera toKlebsiella

“…Spread can occur from a healthcare worker to patients, such as an epidemic of Pseudomonas aeruginosa among neonates cared for by the same nurse during intermittent otitis externa infections, proving ''we are the fomites of disease-the vectors of transmission of nosocomial pathogens'' [48,49]. Direct transmission also occurs with widespread movement of patients and staff between wards, overcrowding, close proximity of patients, and larger numbers of patients per room, such as when four patients are housed together, as was seen in two MRSA outbreaks [15,22].…”

“…This has proved effective for disrupting outbreaks of MRSA [21,22,26,27], VRE [38,39,[41][42][43], ESBL-producing K. pneumoniae [30,[32][33][34], S. marcescens [44], Acinetobacter baumannii [31,[45][46][47], and P. aeruginosa [48].…”

“…Other methods of outbreak control are unit closure [21,30,[42][43][44]48], hiring of additional staff or an infectious disease consultant [22,44], encouraging use of disposable equipment [42], and screening of staff and subsequent reassignment of those colonized to non-clinical duties [15,30,48]. Most of these reports attribute their successful interruption of the outbreak to the practice of cohorting patients and staff.…”

Hand Hygiene

“…[162][163][164] El Shafie and colleagues 164 investigated an outbreak of multidrug-resistant A. baumannii and documented identical strains from patients, hands of staff, and the environment. The outbreak was terminated when remedial measures were taken.…”

“…The outbreak was terminated when remedial measures were taken. Contaminated HCWs' hands were clearly related to outbreaks among surgical 148,162 and neonatal 163,165,166 patients.…”