SARS-CoV-2 Sequence Characteristics of COVID-19 Persistence and Reinfection

Background. Both SARS-CoV-2 reinfection and persistent infection have been described, but a systematic assessment of mutations is needed. We assessed sequences from published cases of COVID-19 reinfection and persistence, characterizing the hallmarks of reinfecting sequences and the rate of viral evolution in persistent infection. Methods. A systematic review of PubMed was conducted to identify cases of SARS-CoV-2 reinfection and persistent infection with available sequences. Amino acid changes in the reinfecting sequence were compared to both the initial and contemporaneous community variants. Time-measured phylogenetic reconstruction was performed to compare intra-host viral evolution in persistent COVID-19 to community-driven evolution. Results. Fourteen reinfection and five persistent infection cases were identified. Reports of reinfection cases spanned a broad distribution of ages, baseline health status, reinfection severity, and occurred as early as 1.5 months or >8 months after the initial infection. The reinfecting viral sequences had a median of 9 amino acid changes with enrichment of changes in the S, ORF8 and N genes. The number of amino acid changes did not differ by the severity of reinfection and reinfecting variants were similar to the contemporaneous sequences circulating in the community. Patients with persistent COVID-19 demonstrated more rapid accumulation of mutations than seen with community-driven evolution with continued viral changes during convalescent plasma or monoclonal antibody treatment. Conclusions. SARS-CoV-2 reinfection does not require an unusual set of circumstances in the host or virus, while persistent COVID-19 is largely described in immunosuppressed individuals and is associated with accelerated viral evolution as measured by clock rates.