Microbial and Cytokine Signatures in Long COVID Patients

Two measures will be obtained from participants' plasma: 1. microbial signatures using Karius' agnostic metagenomic assay via microbial cell-free DNA (mcfDNA) sequencing (kariusdx.com) 2. cytokine signatures using 71-plex and 18-plex assays (evetechnologies.com). The diagnostic utility of the potential biomarkers, including signatures derived from microbial cell-free DNA fragments found in plasma and plasma cytokines, will be evaluated independently and in various combinations to determine whether and to what extent we can accurately identify Long COVID patients. Moreover, we plan to leverage the Karius Test and the underlying Karius microbial cell-free DNA technology to determine whether there is evidence of more frequent reactivations of latent infections in patients with long COVID compared to matched healthy control. Plasma samples will also be stored for future comparative studies of additional immune profiles.