BACKGROUND: Group A Streptococcus (GAS) can cause life-threatening invasive infections, particularly in persons with advanced age and nonintact skin. Both are common among residents of skilled nursing facilities (SNF), where GAS outbreaks can be prolonged. In February 2016, the Pennsylvania Department of Health was notified of a single case of invasive GAS infection in a resident of a 198-bed SNF; we provided recommendations the following day. Three additional GAS infections were reported during March–April. We investigated to identify cases and recommend additional control measures.
METHODS: We defined cases as symptomatic, culture-confirmed GAS infection in residents or staff since January 1, 2016. Cases were categorized as invasive (cultured from a normally sterile site) or noninvasive. We interviewed staff and observed infection control practices. During April–May, all residents (oropharynx, wounds, indwelling catheter sites) and staff (oropharynx, wounds) were screened for asymptomatic GAS. Available isolates were typed at CDC. Whole genome sequencing (WGS) was performed on select isolates.
RESULTS: We identified 1 noninvasive and 3 invasive cases during January–May; two died. Ten asymptomatic carriers (5 residents and 5 staff) were identified, received antibiotics and were recultured. Multiple infection control deficiencies were noted, including inadequate hand hygiene, lack of supplies, and poor technique with personal protective equipment; we provided recommendations to improve these deficiencies. Despite the initial interventions, we identified 2 new invasive cases during June–August; additional screening identified three carriers (2 residents and 1 staff). Among 17 available isolates from 5 cases and 12 carriers (7 resident and 5 staff), fifteen were emm11 and were indistinguishable by WGS. The remaining two staff carriers were emm3.1 and emm89. Because all 6 case-residents had nonintact skin, we recommended infection control review by a certified wound care nurse or infection preventionist; however, this was not implemented by the facility. Mass antibiotic prophylaxis for residents and staff was administered during August 31–September 3, 2016. Those who refused were cultured and treated if GAS was identified. During November, 3 additional cases (2 residents with nonintact skin and 1 staff) occurred; all were emm89 and were indistinguishable by WGS. In total, 9 cases and 13 carriers were identified. Active surveillance is ongoing.
CONCLUSIONS: This prolonged outbreak likely resulted from suboptimal infection control practices. The introduction of a new strain with subsequent intrafacility transmission, despite an aggressive mass prophylaxis campaign, highlights that strong infection control practices, particularly during wound care, are crucial to prevent and control GAS outbreaks among SNF residents.