Strategy in a VA Skilled Nursing Facility Minimizes Both Asymptomatic and Pre-Symptomatic Transmission of COVID-19

BACKGROUND:
Skilled nursing facilities (SNFs) are at high risk for COVID-19 outbreaks. This report presents an outbreak of COVID-19 in a congregate living setting at a VA SNF within the VA Greater Los Angeles Healthcare System (VAGLAHS). Case identification was accomplished by implementing universal and serial laboratory screening, allowing for the rapid isolation of symptomatic and asymptomatic residents with COVID-19.

SUMMARY:

Beginning on March 6 – and prior to any identified cases of COVID-19 – all visitors and staff members were screened for fever, cough, shortness of breath, “flu-like symptoms,” travel, and close contact with known COVID-19 cases before being allowed to enter any patient care areas at VAGLAHS. On March 11, all SNF admissions were halted, and daily temperature and symptom screening began for all residents. On March 17, all visits to SNF wards were curtailed. Despite these precautions, on March 28, 2020, two SNF residents tested positive for severe acute respiratory syndrome coronavirus (SARS-CoV-2) – the virus that causes COVID-19. In response, the VAGLAHS Infection Control team began active case identification through universal and serial laboratory testing of all residents for the virus. All residents with laboratory confirmed infection were transferred to the affiliated hospital for isolation and clinical management. Strategies for case identification and containment also were employed among SNF staff, including clinical providers and ancillary staff. Beginning on March 28, staff were assigned to a single ward vs. working shifts on different wards. From March 29 to April 10, universal testing of all 136 staff identified eight (6%) with positive COVID-19 test results. Staff with laboratory confirmed COVID-19 self-isolated at home. From March 26 through April 6, 19 cases of COVID-19 were diagnosed among 99 SNF residents. No further cases were detected upon further screening of residents on April 13 and April 22-23. At the time of diagnosis, 14 residents were asymptomatic, along with 4 of 8 staff members, highlighting the potential for widespread transmission before illness is recognized. Eight of the asymptomatic residents later developed symptoms.

This outbreak report demonstrates the utility of universal serial laboratory screening to identify cases to rapidly isolate or cohort to reduce transmission. This strategy limited potential asymptomatic and pre-symptomatic transmission of COVID-19, allowing for successful containment. The outbreak in one ward was suppressed within 1 week, the outbreak in a second ward was suppressed within 2 weeks, and no cases occurred in a third ward.

IMPLICATIONS:

• Universal and serial SARS-CoV-2 testing in SNFs can identify cases during an outbreak, and rapid isolation and cohorting can minimize ongoing transmission.

AUTHOR/FUNDING INFORMATION:
This study was funded by HSR&D. Drs. Graber and Goetz are part of HSR&D’s Center for Healthcare Innovation, Implementation and Policy (CSHIIP), Los Angeles, CA. All authors are part of the VA Greater Los Angeles Healthcare System.

Dora A, Winnett A, Jatt L, Davar K, Watanabe M, Sohn L, Kern H, Graber C, and Goetz M. Universal and Serial Laboratory Testing for SARS-CoV-2 at a Long-Term Care Skilled Nursing Facility for Veterans – Los Angeles, California, 2020. Morbidity and Mortality Weekly Report (MMWR). May 29, 2020;69(21):651-55.