Outbreak of multiresistant OXA-24- and OXA-51-producing Acinetobacter baumannii in an internal medicine ward

Daniel Tena1, Nora Mariela Martínez, Jesús Oteo

  • 1Sección de Microbiología, Hospital Universitario de Guadalajara, Guadalajara, Spain. danielt@sescam.jccm.es

Insights

A multidrug-resistant Acinetobacter baumannii outbreak occurred in a hospital, affecting five patients and the environment. Strict adherence to infection control measures by healthcare workers is crucial to prevent serious consequences.

Area of Science:

  • Infectious Diseases
  • Clinical Microbiology
  • Epidemiology

Background:

  • An outbreak of multidrug-resistant Acinetobacter baumannii (MRAB) occurred in an internal medicine ward.
  • The outbreak involved five patients over a six-week period, with various infections and one fatality.

Observation:

  • MRAB isolates were recovered from five patients and one environmental sample.
  • All isolates belonged to a single clone (ST79), positive for blaOXA-24 and blaOXA-51 carbapenemases.
  • The outbreak strain was found on a serum container, suggesting healthcare worker transmission.

Findings:

  • Four patients died; one death was likely due to A. baumannii meningitis.
  • The study identified a single clone of MRAB responsible for the outbreak.
  • Carbapenemase genes blaOXA-24 and blaOXA-51 were present in all isolates.

Implications:

  • Highlights the critical need for strict infection control practices among healthcare workers.
  • Underscores the potential for rapid spread and severe outcomes of MRAB outbreaks.
  • Emphasizes the importance of environmental monitoring and molecular typing in outbreak investigations.

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