1615. Influenza Outbreaks in Long-Term Care Facilities, 2017–2018 Influenza Season, Dallas, Texas

BACKGROUND: High rates of influenza-related hospitalizations and deaths occurred in the United States during the 2017–2018 influenza season. A record number of influenza outbreaks were reported in long-term care facilities (LTCF) in Dallas County. Public health surveillance of influenza-related intensive care unit (ICU) admissions and deaths in acute care hospitals improved early identification of outbreaks in LTCFs. METHODS: A confirmed LTCF influenza outbreak was defined as at least 1 lab-confirmed influenza case plus at least 1 case of influenza-like illness among residents or staff within 72 hours. Outbreaks were self-reported by facilities or identified by the health department during investigations of ICU hospitalizations and deaths. CDC guidance for influenza outbreak management was provided and daily active surveillance was continued for at least 1 week after the last case was identified. Data collected included: numbers of ill residents and staff, vaccination rates, dates of illness and chemoprophylaxis initiation, hospitalizations and deaths. Fisher exact tests and Chi-square were performed using SAS 9.4. RESULTS: During this influenza season, 32 confirmed influenza outbreaks were identified in Dallas County LTCFs: 17 in skilled nursing facilities (SNF), 13 in assisted-living facilities (ALF) and 2 in hybrid SNF/ALF. The average attack rate in residents was 9.8% (range: 1–35%). Influenza hospitalization rates were higher in ALF compared with SNF outbreaks (OR: 2.2). Influenza-associated mortality rates were higher in ALF compared with SNF (OR: 3.1). Of the 32 outbreaks, 20 (63%) were self-reported by facilities to public health and 12 (38%) were identified through health department review of influenza-associated ICU hospitalizations. Facilities where outbreak cases were identified through public health surveillance of ICU admissions had significantly lower overall attack rates (5.9% vs. 12.1%, P = 0.01) and shorter time to initiation of facility-wide chemoprophylaxis (0.4 vs. 2.4 days, P = 0.05). CONCLUSION: Active surveillance of influenza-associated ICU admissions in acute-care hospitals facilitated the early identification of influenza outbreaks in LTCFs, which was associated with lower overall attack rates and shorter time to initiation of facility-wide chemoprophylaxis. DISCLOSURES: All authors: No reported disclosures.