Community-Acquired Methicillin-Resistant Staphylococcus aureus in Institutionalized Adults With Developmental Disabilities

Abraham Borer, Jacob Gilad, Pablo Yagupsky, Nechama Peled, Nurith Porat, Ronit Trefler, Hannah Shprecher-Levy, Klaris Riesenberg, Miriam Shipman, and Francisc Schlaeffer


Emerging Infectious Diseases. 2002;8(9) 

In This Article

Abstract and Introduction

Methicillin-resistant Staphylococcus aureus (MRSA) has recently been reported to emerge in the community setting. We describe the investigation and control of a community-acquired outbreak of MRSA skin infections in a closed community of institutionalized adults with developmental disabilities. In a 9-month period in 1997, 20 (71%) of 28 residents had 73 infectious episodes. Of the cultures, 60% and 32% obtained from residents and personnel, respectively, grew S. aureus; 96% and 27% were MRSA. All isolates were genetically related by pulsed-field gel electrophoresis and belonged to a phage type not previously described in the region. No known risk factors for MRSA acquisition were found. However, 58 antibiotic courses had been administered to 16 residents during the preceding 9 months. Infection control measures, antibiotic restriction, and appropriate therapy resulted in successful termination of this outbreak. Selective antibiotic pressure may result in the emergence, persistence, and dissemination of MRSA strains, causing prolonged disease.

Methicillin-resistant Staphylococcus aureus (MRSA) poses a therapeutic challenge in acute-care settings,[1,2,3,4] as well as long-term skilled-nursing facilities.[5,6,7,8] Recently, MRSA has also been detected in the community more often. The terms and definitions related to community-acquired MRSA remain controversial, and the "community" as a milieu for MRSA acquisition cannot be implicated with a high degree of certainty. Most studies have defined community acquisition as growth within 48-72 hours after hospital admission,[9,10,11] which does not rule out nosocomial acquisition. Patients thought to have acquired MRSA in the community carry risk factors implicated in nosocomial acquisition.[12,13,14,15,16]

Outbreaks of community-acquired MRSA infection are extremely rare.[17,18,19] During 1997, we investigated an outbreak of skin and soft-tissue infection involving MRSA in a closed community of institutionalized adults with developmental disabilities. MRSA emerged and disseminated in this setting as a result of an extreme selective pressure exacerbated by heavy and continuous use of ineffective antimicrobial drugs. That such selective pressure was sufficient to promote MRSA emergence in the community underlines the threat associated with current antibiotic prescribing practices in the community.