Persistent fatigue following SARS-CoV-2 infection is common and independent of severity of initial infection

Townsend, L.; Dyer, A. H.; Jones, K.; Dunne, J.; Kiersey, R.; Gaffney, F.; O'Connor, L.; Mooney, A.; Leavy, D.; Ridge, K.; King, C.; Cox, F.; O'Brien, K.; Dowds, J.; Sugrue, J.; Hopkins, D.; Byrne, P.; Kingston, T.; Ni Cheallaigh, C.; Nadarajan, P.; McLaughlin, A. M.; Bourke, N. M.; Bergin, C.; O'Farrelly, C.; Bannan, C.; Conlon, N.

Fatigue is a common symptom in those presenting with symptomatic COVID-19 infection. However, it is unknown if COVID-19 results in persistent fatigue in those recovered from acute infection. We examined the prevalence of fatigue in individuals recovered from the acute phase of COVID-19 illness using the Chalder Fatigue Score (CFQ-11). We further examined potential predictors of fatigue following COVID-19 infection, evaluating indicators of COVID-19 severity, markers of peripheral immune activation and circulating pro-inflammatory cytokines. Of 128 participants (49.5 {+/-} 15 years; 54% female), more than half reported persistent fatigue (52.3%; 45/128) at 10 weeks (median) after initial COVID-19 symptoms. There was no association between COVID-19 severity (need for inpatient admission, supplemental oxygen or critical care) and fatigue following COVID-19. Additionally, there was no association between routine laboratory markers of inflammation and cell turnover (leukocyte, neutrophil or lymphocyte counts, neutrophil-to-lymphocyte ratio, lactate dehydrogenase, C-reactive protein) or pro-inflammatory molecules (IL-6 or sCD25) and fatigue post COVID-19. Female gender and those with a pre-existing diagnosis of depression/anxiety were over-represented in those with fatigue. Our findings demonstrate a significant burden of post-viral fatigue in individuals with previous SARS-CoV-2 infection after the acute phase of COVID-19 illness. This study highlights the importance of assessing those recovering from COVID-19 for symptoms of severe fatigue, irrespective of severity of initial illness, and may identify a group worthy of further study and early intervention.