2653. Duration of Respiratory Virus Detection by Multipathogen PCR Testing after Acute Respiratory Illness

Abstract

Abstract Background Persons with respiratory viral infections (RVI) may shed detectable virus after symptom recovery. Duration of detection by molecular methods is not well described for non-SARS-CoV-2 respiratory viruses. Methods School KIDS is a prospective respiratory viral surveillance program in a Missouri school district. Participating students and staff with RVI symptoms can receive respiratory viral testing using self-collected nasal swabs. Symptomatic participants with detectable virus(es) on primary swabs were scheduled to receive 2 convalescent swabs weekly after initial test during weekly school surveillance testing. All convalescent tests performed within 21 days of the primary specimen were included. Only participants providing ≥ 1 convalescent swab were included. Specimens were tested using Hologic® Panther Fusion® or QIAstat-Dx PCR assays that included adenovirus (AdV); seasonal coronaviruses (sCoV) 229E, HKU1, NL63, OC43; human metapneumovirus, influenza A and B (Flu), parainfluenza viruses 1-4, respiratory syncytial virus, rhinovirus/ enterovirus (RV/EV), and SARS-CoV-2. We used survival analysis to quantify median number of days until individuals tested negative for each virus. Results From November 3, 2022 – April 14, 2023, 344 symptomatic participants (141 preK/elem, 49 middle, 22 high, 132 staff) submitted 586 primary specimens; 292 (50%) were positive for a virus. For positive primary specimens, median [IQR] time of symptom onset to specimen collection was 2 [1,3] days. A total of 320 viruses were detected; most common were RV/EV (37%) and sCoVs (25%) (Table). An additional 370 convalescent specimens were collected (87 specimens on days 1-7 following primary positive; 166 specimens on days 8-14; and 117 specimens on days 15-21). Median number of days [95% confidence interval] when repeat convalescent tests became negative varied by virus (AdV 15 [11,undefined] days, Flu A 14 [9,19] days, RV/EV 12 [11,14] days, SARS-CoV-2 14 [14,17] days, sCoV 10 [9,12] days) (Figure).Table.Characteristics of primary positive and convalescent testing (i.e. ongoing positivity) of nasal swabs from preK—12 grade students and staff with respiratory symptoms—Missouri, November 2022 -April 2023Figure.Cumulative probability of testing negative for a respiratory virus on subsequent respiratory viral testing Conclusion Students and staff continued to have detectable virus by nasal swabs 10-15 days after symptomatic positive specimen. Further data are needed to determine when participants are no longer infectious. Disclosures Rangaraj Selvarangan, BVSc, PhD, D(ABMM), FIDSA, FAAM, Abbott: Honoraria|Altona Diagnostics: Grant/Research Support|Baebies Inc: Advisor/Consultant|BioMerieux: Advisor/Consultant|BioMerieux: Grant/Research Support|Bio-Rad: Grant/Research Support|Cepheid: Grant/Research Support|GSK: Advisor/Consultant|Hologic: Grant/Research Support|Lab Simply: Advisor/Consultant|Luminex: Grant/Research Support