Outbreak of community-acquired methicillin-resistant Staphylococcus aureus skin infections among health care workers in a cancer center.
BACKGROUND
The incidence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) soft tissue infections is rising. However, CA-MRSA outbreaks among health care workers (HCWs) are rarely reported. We describe 3 clusters of CA-MRSA soft tissue infections among HCWs and the subsequent transmission to a patient.


METHODS
The first cluster of boils occurred in 4 employees who worked in the ambulatory treatment clinic (area A) and 1 patient (PA1) who frequently visited area A. Three employees (EA1, EA2, and EA3) and PA1 had positive cultures. Twelve employees in 2 geographically separate diagnostic imaging areas (areas B and C) reported recent or current boils of whom EB1, EB2, EB3, and EC1 had positive cultures. Molecular subtyping using pulse-field gel electrophoresis (PFGE) was performed on all 8 isolates and confirmed by the Centers for Disease Control and Prevention laboratory.


RESULTS
Relatedness of the MRSA strain was confirmed by PFGE in 7 of 8 isolates. Only EB3 was not related to the prototype CA-MRSA strain. All 7 related MRSA strains contained the typical genetic organization of staphylococcal cassette chromosome (SCC)-mec type IVa plus genes encoding Panton-Valentine Leukocidin. EB3's strain contained SCC-mec type II and was Panton-Valentine Leukocidin negative. A total of 171 questionnaires was sent. Nine of the 85 HCWs who responded reported a recent or current history of boils. Infection control conducted an education program for employees in areas A, B, and C.


CONCLUSIONS
Early identification and control of CA-MRSA infections among HCWs is important to limit horizontal transmission to patients. Future efforts should include educational programs and guidelines for reporting and treating HCWs with MRSA infections.
Kassis
Christelle
C
Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA.
Hachem
Ray
R
Raad
Issam I
II
Perego
Cheryl A
CA
Dvorak
Tanya
T
Hulten
Kristina G
KG
Frenzel
Elizabeth
E
Thomas
Georgia
G
Chemaly
Roy F
RF
D000046:Academic Medical Centers; D017714:Community-Acquired Infections / Q000453:epidemiology*; D004196:Disease Outbreaks; D005667:Furunculosis / Q000453:epidemiology* / Q000382:microbiology; D006282:Health Personnel; D006801:Humans; D017757:Infectious Disease Transmission, Professional-to-Patient / Q000706:statistics & numerical data; D055624:Methicillin-Resistant Staphylococcus aureus / Q000235:genetics / Q000302:isolation & purification; D013781:Texas / Q000453:epidemiology