BACKGROUND: In February, 2016, the Cook County Department of Public Health (CCDPH) identified a group A Streptococcus (GAS) outbreak associated with long-term care facility (LTCF) A. CCDPH initiated an epidemiologic investigation, including a carriage survey and a case-control study. Infection control observations and policy review helped identify lapses in practices and protocols, particularly those associated with wound care equipment and practices.
METHODS: Between February and April 2016, 7 GAS cases with history of recent admission to LTCF A were identified after they were admitted to local hospitals. Available isolates were identified as type 89.0 by emm typing performed at CDC’s Streptococcal laboratory. A case was defined as a patient with history of recent admission to LTCF A with a positive culture for GAS emm type 89.0. Three health care providers identified as asymptomatic GAS carriers were colonized by emm types that differed from the outbreak strain and from one another. A chart review found that all cases had a history of chronic wounds. A screening of wounds identified four cases of GAS carriage. Additionally, four residents who had previously screened negative later developed GAS infection during the surveillance period. To determine risk factors for acquiring GAS, a case-control study was conducted using 15 case-residents and 21 control-residents (residents with a negative surveillance culture in wound who did not develop infections at a later time).
RESULTS: Multiple lapses in infection control practices during wound care therapy and Vacuum Assited Closure VAC placement/replacement were noted. Wound care therapy equipment included electrical stimulators, ultrasounds, ultrasound mist devices, ultrasound diathermy devices and ultraviolet light devices. Protocols for use, cleaning and disinfection of these devices were either not available, insufficient, or not enforced. Environmental specimens were collected from ready-to-use equipment and frequently touched surfaces and were sent for culture. Multiple microorganisms, including GAS, were recovered in six of ten specimens; GAS identified from a bedside table matched the outbreak emm type. LTCF A removed VACs and all equipment used to provide wound care therapy from service until protocols were developed, reviewed and implemented according to recommendations. Competency-based training for all staff responsible for use, cleaning, and disinfection of this equipment was conducted. History of undergoing wound care therapy or VAC placement at facility A was strongly associated with case status.
CONCLUSIONS: This investigation highlights the potential for GAS transmission in patients with chronic wounds who receive wound care therapy and VAC.