Longest COVID-19 infection lasted 505 days in an immunocompromised person in London

Simon Collins, HIV i-Base

A UK study of nine group people with significantly reduced immune protection and extended COVID-19 infections, managed at Guy’s and St Thomas’s NHS Trust in London, includes the longest active infection reported globally to date.

This cohort was enroled between March 2020 and December 2021 were immunocompromised  due to organ transplant, HIV, cancer, or due to treatments with chemotherapy or biologic antibodies associated due to other underlying conditions.

This study date was reported by Medscape ahead of presentation at the European Congress of Clinical Microbiology & Infectious Diseases on 25 April 2022. [1, 2]

All participants tested positive for SARS-CoV-2 for at least eight weeks (mean 73 days) with 2/9 having persistent infection for over a year. Although some remained asymptomatic, 4/9 have died, including the case of an infection lasting 505 days. COVID-19 as not always reported as the cause of death.

Phylogenetic analysis confirmed the continuous infection was not due to reinfection, and also tracked the development of multiple mutations associated with variants of concern (including Alpha, Delta, and Omicron variants). One person developed 10 mutations that have arisen separately in these variants.

Of the five patients who are still alive, 2/5 cleared the infection and one has continued for more than 430 days, and will clear 505 days if they are still positive at the next follow up appointment.

This report stressed the importance of finding effective strategies to prevent infection in people who are most vulnerable to infection. Although monoclonal antibodies can be used in people with reduced immunity if vaccines fail to generate protection, those currently licensed in the UK are not active against the latest Omicron BA.2 variants.


  1. McCall B. Patient identified who battled COVID for 505 days. Medcape. (22 April 2022).
  2. Snell LB et al. A longitudinal study of evolution of SARS-CoV-2 variants in immunocompromised individuals with persistent infection. European Congress of Clinical Microbiology & Infectious Diseases (ECCMID). Lisbon. 253-26 April 2022. Abstract L0535.

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