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Survey of methicillin-resistant Staphylococcus aureus from neonates and the environment in the NICU

Shigeru Fujimura1, Seiichi Kato, Motoya Hashimoto

  • 1Department of Microbiology, Miyagi University, 1 Gakuen, Taiwa-cho, Miyagi 981-3298, Japan. hujimura@myu.ac.jp

Journal of Infection and Chemotherapy : Official Journal of the Japan Society of Chemotherapy
|May 26, 2004
PubMed

Insights

Methicillin-resistant Staphylococcus aureus (MRSA) is a growing concern in Japanese neonatal intensive care units (NICUs). This study found persistent MRSA strains in NICU patients and environments, highlighting the need for environmental controls to prevent nosocomial infections.

Area of Science:

  • Medical Microbiology
  • Infectious Diseases
  • Hospital Epidemiology

Background:

  • Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant risk for nosocomial infections in vulnerable populations, particularly neonates.
  • Increasing prevalence of MRSA carriage among children in Japan necessitates investigation into healthcare-associated MRSA transmission.
  • Previous reports indicate MRSA-related nosocomial infections in pediatric and neonatal intensive care units (NICUs).

Purpose of the Study:

  • To investigate the prevalence and genetic types of MRSA strains isolated from neonates and their NICU environments.
  • To determine the persistence of specific MRSA genotypes within the NICU setting over a 6-month period.
  • To assess the potential for MRSA transmission between neonates and their immediate surroundings.

Main Methods:

  • Collection of 37 MRSA strains from neonates and 52 strains from NICU environments over 6 months (January-June 2001).
  • DNA typing of isolated MRSA strains using arbitrary primed-PCR (AP-PCR) to classify genotypes.
  • Analysis of MRSA strain distribution and persistence in both clinical and environmental samples.

Main Results:

  • Thirty-seven clinical MRSA isolates were classified into four main types (A, B, C, D) and others.
  • A specific MRSA genotype (A type) was persistently isolated from patients for over 6 months.
  • The A-type MRSA was detected in 23.1% of environmental samples and frequently found in patient vicinity areas.

Conclusions:

  • The A-type MRSA genotype demonstrated significant persistence in the NICU, suggesting a potential source of nosocomial infection.
  • While severe MRSA infections were not observed in the neonates, the continuous isolation of the same genotype from patients and the environment underscores transmission risks.
  • Implementing stringent environmental controls within NICUs is crucial for preventing MRSA acquisition and nosocomial infections in neonates.

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