2307. Respiratory Virus Testing Strategy on Admission to Hospital in a Season where SARS-CoV-2 is Co-circulating with Seasonal Respiratory Viruses

Abstract Background Syndromic multiplex testing is the mainstay of viral respiratory surveillance, yet some evidence supports the use of asymptomatic testing for SARS-CoV-2 on patient admission. We conducted a prospective quality improvement study to determine the adherence and outcomes associated with a hybrid surveillance strategy for patients being admitted to an acute care hospital who underwent testing on admission. Methods In November, 2022, corporate education recommended that patients with compatible viral respiratory symptoms undergo respiratory multiplex testing for 15 viral pathogens, while those without viral respiratory symptoms (considered asymptomatic) undergo SARS-CoV-2 PCR testing alone. Between December 1, 2022 to March 30, 2023, we measured the testing strategy using positivity rate, rate of omission (i.e., SARS-CoV-2 testing for symptomatic patients, defined as needing a repeat swab for multiplex within 24-hours of admission), and rate of commission (i.e., multiplex testing for asymptomatic patients). Those with detection of non-SARS-CoV-2 respiratory viruses in absence of symptoms were prospectively assessed for 24 hours for development of symptoms and roommate contacts underwent syndromic surveillance for 72-hours. Results Among 5659 patients tested on admission, 2868(50.6%) underwent multiplex testing while 2791(49.3%) were tested only for SARS-CoV-2. The positivity rate for multiplex testing, positivity rate for COVID SARS-CoV-2 testing, omission rate and commission rate were 249/2868(8.7%), 81/2791 (2.9%), 259/1403(17.8%), 1618/4091(39.6%), respectively. Symptom status for 165 patients was not available. Asymptomatic non-SARS-CoV-2 positive patients made up 0.6% of all admissions, of whom none developed symptoms within 24 hours, and the attack rate among roommate contacts was zero (0/20). There were only 31 additional days of precautions for asymptomatic non-SARS-CoV-2 respiratory virus detection that made up 4.4% of overall precaution-days for respiratory virus infection. Conclusion A hybrid surveillance strategy for patients admitted to hospital based on presence of symptoms was implemented with relatively low rates of repeat testing and asymptomatic non-SARS-CoV-2 virus detection. Disclosures Jerome A. Leis, MD MSc FRCPC, Ontario Hospital Association, Ministry of Attorney General of Ontario, Seneca College: Expert Testimony