Successive SARS-CoV-2 mutations in a highly susceptible host: A case report of persistent viremia and fatality.

A 71-year-old female with post-treatment follicular lymphoma developed COVID-19 with persistent viremia. Despite the initiation of remdesivir on day 23, she remained SARS-CoV-2 PCR-positive and ultimately succumbed to respiratory failure on day 79. Whole-genome analysis of RNA extracted from a post-mortem nasopharyngeal swab identified multiple mutations, including P323L/G671S, which enhances viral replication, and V792I, associated with remdesivir resistance. This case highlights the challenges of managing persistent SARS-CoV-2 infection in immunocompromised patients and underscores the impact of delayed treatment and antiviral resistance.