Addendum to: Nature Medicine; published online 19 March 2020

On 17 April 2020, the Wuhan Municipal Health Commission revised the official COVID-19 death counts in Wuhan up by 1,290 to 3,869. No new information on the age distribution of COVID-19 deaths in China has been published since February 2020. In light of the changes in the number of fatalities in Wuhan, we are providing a revised estimate of clinical severity as follows, assuming that the age distribution of COVID-19 deaths remains the same as before.

We assumed that the abovementioned revision of the total number of COVID-19 deaths in Wuhan would increase the number of confirmed COVID-19 deaths during our study period by the same proportion; i.e., from 2,169 to 2,169 × 3,869 / (3,869 – 1,290) = 3,254. The resulting age-specific symptomatic case-fatality risks (sCFRs) are shown in Fig. 1 in this Addendum. The overall sCFR would increase to 2.2% (95% credible interval, 1.4–3.2%), 2.0% (1.2–3.4%) or 1.8% (1.0–2.8%) if the probability of developing symptoms after infection (Psym) was 0.5, 0.75 or 0.95, respectively. If Psym = 0.5, the sCFRs are 0.5% (0.2–1.0%), 0.8% (0.5–1.2%) and 3.9% (2.6–5.9%) for those <30 years of age, 30–59 years of age and >59 years of age, respectively.

Fig. 1: Estimates of age-specific sCFR values and susceptibility to symptomatic infection for COVID-19 in Wuhan.
figure 1

a, Estimates of age-specific sCFRs, assuming Psym is 0.5 (red), 0.75 (green) or 0.95 (blue). b, Estimate of relative susceptibility to symptomatic infection by age, assuming Psym is 0.50 (red), 0.75 (green) or 0.95 (blue). Symbols in a,b show the posterior means, and the bars show 95% credible intervals.

We will update our estimates again as and when new and more detailed information, including the total number and age distribution of COVID-19 deaths, are made available.