Long-term SARS-CoV-2 RNA shedding and its temporal association to IgG seropositivity

Abstract

With anecdotal reports of viral shedding from COVID-19 patients for several weeks, there is a need to quantify the prevalence of long-term SARS-CoV-2 shedding. Here, we characterize the temporal distribution of diagnostic SARS-CoV-2 PCR outcomes from nasopharyngeal swabs and associated EHR-derived features over two months for 874 COVID-19 patients with longitudinal data. Among a cohort of 379 COVID-19 patients with at least one positive follow-up SARS-CoV-2 PCR test, 53 patients remain SARS-CoV-2-positive after four weeks of initial diagnosis. Surprisingly, a majority of COVID-19 patients with long-term viral shedding are not hospitalized (40 of 53 patients), and have no enrichments among symptoms, demographics, or medical history. In a cohort of 370 COVID-19 patients that transition to a confirmed negative status, the upper bound of viral shedding duration has a mean of 21.2 days with standard deviation of 9.3 days. Of the 81 PCR-confirmed COVIDpos patients who have undergone serologic testing, 68 patients have developed anti-SARS-CoV-2 IgG to date, with a mean upper bound of time to seroconversion of 38.1 days (95% C.I. = 35.2-41.1 days). Given that SARS-CoV-2 PCR testing may detect replication incompetent virus and that serologic tests do not imply neutralizing immunity, we suggest that the development of novel assays for measuring infectious viral load in non-hospitalized long-term shedders may help mitigate community transmission. This study motivates a platform that can link longitudinal diagnostic and serologic testing with real-time epidemiological data, towards proactively identifying and managing emerging hotspots of COVID-19. ### Competing Interest Statement ADB is supported by Grants AI 110173 and AI120698 from NIAID, 109593 62 RGRL from Amfar, and the HH Sheikh Khalifa Bin Zayed Al-Nahyan named professorship from Mayo Clinic. ADB is a consultant for Abbvie, is on scientific advisory boards for Nference and Zentalis, and is founder and President of Splissen therapeutics. One or more of the investigators associated with this project and Mayo Clinic have a Financial Conflict of Interest in technology used in the research and that the investigator(s) and Mayo Clinic may stand to gain financially from the successful outcome of the research. The title of the project is IRB 20-003334: 'CDAP Study of COVID-19 patient characteristics with augmented curation of Electronic Health Records (EHR) to inform strategic and operational decisions'. This research has been reviewed by the Mayo Clinic Conflict of Interest Review Board and is being conducted in compliance with Mayo Clinic Conflict of Interest policies. Authors affiliated with nference have financial interests in nference. ### Funding Statement ADB is supported by Grants AI 110173 and AI120698 from NIAID, 109593-62-RGRL from Amfar, and the HH Sheikh Khalifa Bin Zayed Al-Nahyan named professorship from Mayo Clinic. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Mayo Clinic IRB and compliance body approved this research under the IRB20-003334: CDAP Study of COVID-19 patient characteristics with augmented curation of Electronic Health Records (EHR) to inform strategic and operational decisions. All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes Please contact authors regarding data availability.