Estimating the total morbidity burden of COVID-19

Smith, M. P.

Background Calculations of disease burden of COVID-19 are used to allocate scarce resources and historically have focused on mortality, with little attention to morbidity such as postviral post-COVID, similar to chronic fatigue syndrome (CFS), which strikes 4 and 16% of male and female survivors. This paper quantifies post-COVID disability burden and combines it with case fatality to estimate total morbidity per COVID-19 case. Methods Healthy life years lost per COVID-19 case were computed as the sum of (incidence*disability weight*remaining lifespan) for death and post-COVID (modeled as CFS) by sex and 10-year age category. In addition to death, the main model considered lifelong mild, moderate or severe CFS; Model 2, CFS which resolved in ten years; Model 3, no CFS but 10% risk of death 10 years later. Results In all models, acute mortality was only a small share of total morbidity. For lifelong moderate CFS symptoms, healthy years lost per COVID-19 case ranged from 0.92 (male in his 30s) to 5.71 (girl under 10) and were 3.5 and 3.6 for the oldest females and males. At higher symptom severities, young people and females bore larger shares of total morbidity; if symptoms were persistent or survivors had later increased mortality, young people of both sexes were at highest risk. Conclusions Compared to post-COVID, acute mortality contributes only a small share of total COVID-19 morbidity. Total burden falls heavily on the young, who are currently deprioritized for preventive interventions such as vaccines. To fairly allocate scarce resources, decisionmakers should consider all morbidity.