Identification and control of an outbreak of ciprofloxacin-susceptible EMRSA-15 on a neonatal unit.
We report the identification and control of an outbreak of a ciprofloxacin-susceptible strain of UK epidemic meticillin-resistant Staphylococcus aureus (EMRSA)-15 on a neonatal unit (NNU). All babies were screened for MRSA on admission using ciprofloxacin-containing media which did not detect the outbreak strain. The first identified case was a premature baby who developed MRSA bacteraemia with associated tibial osteomyelitis and multiple subcutaneous abscesses. The outbreak strain was subsequently identified in the nasopharyngeal secretions of a second child who was not clinically infected. Screening of all patients on the NNU using non-ciprofloxacin-media identified two other colonised babies. All four patient isolates were EMRSA-15, spa type t022, SCCmec IV, Panton-Valentine leucocidin (PVL) negative, indistinguishable by pulsed-field gel electrophoresis and susceptible to all non-beta-lactam antimicrobials tested. The outbreak strain was cultured from four of 48 environmental sites in a communal milk-expressing room. Unsupervised movement of mothers to and from the milk-expressing room may have contributed to the outbreak. Control measures included cohort isolation of affected babies, improved environmental cleaning, increased emphasis on hand hygiene and education of mothers. Ciprofloxacin-containing media should be used with caution for MRSA screening in settings where ciprofloxacin-susceptible strains (including community-associated MRSA) are increasing in prevalence.
Otter
J A
JA
Infection and Immunology Delivery Unit, St Thomas' Hospital and King's College London, London, UK.
Klein
J L
JL
Watts
T L
TL
Kearns
A M
AM
French
G L
GL
D000038:Abscess / Q000382:microbiology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016470:Bacteremia / Q000382:microbiology; D015373:Bacterial Typing Techniques; D001431:Bacteriological Techniques / Q000379:methods; D002353:Carrier State / Q000382:microbiology; D002939:Ciprofloxacin / Q000494:pharmacology*; D003428:Cross Infection / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D003470:Culture Media / Q000737:chemistry; D004196:Disease Outbreaks; D024881:Drug Resistance, Bacterial; D004493:Education; D004783:Environmental Microbiology; D004917:Erythromycin / Q000494:pharmacology*; D005260:Female; D005838:Genotype; D006235:Hand Disinfection; D006797:Housekeeping, Hospital; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008131:London / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D009305:Nasopharynx / Q000382:microbiology; D010019:Osteomyelitis / Q000382:microbiology; D010356:Patient Isolation; D010641:Phenotype; D013203:Staphylococcal Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000302:isolation & purification
D000900:Anti-Bacterial Agents; D003470:Culture Media; D002939:Ciprofloxacin; D004917:Erythromycin