Estimating clinical severity of COVID-19 from the transmission dynamics in Wuhan, China

Nat Med. 2020 Apr;26(4):506-510. doi: 10.1038/s41591-020-0822-7. Epub 2020 Mar 19.

Abstract

As of 29 February 2020 there were 79,394 confirmed cases and 2,838 deaths from COVID-19 in mainland China. Of these, 48,557 cases and 2,169 deaths occurred in the epicenter, Wuhan. A key public health priority during the emergence of a novel pathogen is estimating clinical severity, which requires properly adjusting for the case ascertainment rate and the delay between symptoms onset and death. Using public and published information, we estimate that the overall symptomatic case fatality risk (the probability of dying after developing symptoms) of COVID-19 in Wuhan was 1.4% (0.9-2.1%), which is substantially lower than both the corresponding crude or naïve confirmed case fatality risk (2,169/48,557 = 4.5%) and the approximator1 of deaths/deaths + recoveries (2,169/2,169 + 17,572 = 11%) as of 29 February 2020. Compared to those aged 30-59 years, those aged below 30 and above 59 years were 0.6 (0.3-1.1) and 5.1 (4.2-6.1) times more likely to die after developing symptoms. The risk of symptomatic infection increased with age (for example, at ~4% per year among adults aged 30-60 years).

Publication types

  • Letter
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Factors*
  • Aged
  • Aged, 80 and over
  • Asymptomatic Diseases
  • Betacoronavirus
  • COVID-19
  • COVID-19 Testing
  • Child
  • Child, Preschool
  • China / epidemiology
  • Clinical Laboratory Techniques
  • Coronavirus Infections* / complications
  • Coronavirus Infections* / diagnosis
  • Coronavirus Infections* / epidemiology
  • Female
  • Humans
  • Infant
  • Male
  • Middle Aged
  • Models, Statistical*
  • Mortality
  • Pandemics*
  • Pneumonia, Viral* / complications
  • Pneumonia, Viral* / diagnosis
  • Pneumonia, Viral* / epidemiology
  • Prognosis
  • Real-Time Polymerase Chain Reaction
  • Risk Factors
  • SARS-CoV-2
  • Severity of Illness Index*