Case reports of persistent SARS-CoV-2 infection outline within-host viral evolution in immunocompromised patients

Heat map construction provided evidence of gain and/or loss of mutations over time for both patients, suggesting within-host genomic evolution of the virus. In addition, mutation polymorphisms and changes in the SARS-CoV-2 lineage were observed in Patient B. Sequence analysis revealed high mutational pattern variability, reflecting the high complexity of viral replication dynamics in fragile patients.