11/27/2025
A man had COVID-19 for more than two years – without ever clearing the virus - A 41-year-old immunocompromised man in the US carried an active COVID-19 infection for over 750 days, setting what researchers believe is a new record. This wasn’t long COVID – his body never cleared the virus. It just kept mutating inside him. Between 2020 and 2022, he was hospitalized five times and suffered ongoing respiratory symptoms, headaches, and weakness. The patient, who has advanced HIV and a critically low immune T-cell count (35 cells/μL, where healthy ranges are 500–1,500), was unable to access antiretroviral treatment during the early stages of infection. Scientists tracked how the virus evolved inside him using genetic analysis. Over two years, it accumulated mutations at a rate similar to what we see across entire populations. Some of those mutations closely resembled ones found in the Omicron variant – including changes to the spike protein that help the virus enter cells more easily. That’s what makes this case so important: it shows how long-term infections in vulnerable individuals can act like miniature incubators, allowing the virus to explore mutations that may one day spread to the broader population. Thankfully, in this case, the mutated virus wasn’t very transmissible. But researchers caution that this isn't always the outcome. Clearing persistent infections like this one isn’t just critical for the individual’s health – it’s a public health priority. Experts say that preventing future variants starts with ensuring access to treatment, supporting vaccination, and monitoring viral evolution in vulnerable patients. Read the study: "Characterisation of a persistent SARS-CoV-2 infection lasting more than 750 days in a person living with HIV: a genomic analysis." The Lancet, September 2025.