From Jamie's link: (hyper link near the top of the stat analysis 'one in 10 infected people'
Report of the WHO-China Joint Mission
on Coronavirus Disease 2019 (COVID-19)
16-24 February 2020
Contact Tracing
China has a policy of meticulous case and contact identification for COVID-19. For example,
in Wuhan more than 1800 teams of epidemiologists, with a minimum of 5 people/team, are tracing tens of thousands of contacts a day. Contact follow up is painstaking, with a high percentage of identified close contacts completing medical observation. Between 1% and 5% of contacts were subsequently laboratory confirmed cases of COVID-19, depending on location. For example:
• As of 17 February, in Shenzhen City, among 2842 identified close contacts, 2842
(100%) were traced and 2240 (72%) have completed medical observation. Among
the close contacts, 88 (2.8%) were found to be infected with COVID-19.
• As of 17 February, in Sichuan Province, among 25493 identified close contacts,
25347 (99%) were traced and 23178 (91%) have completed medical observation.
Among the close contacts, 0.9% were found to be infected with COVID-19.
• As of 20 February, in Guangdong Province, among 9939 identified close contacts,
9939 (100%) were traced and 7765 (78%) have completed medical observation.
Among the close contacts, 479 (4.8%) were found to be infected with COVID-19.
Roughly 40000 close-contacts were tested and observed resulting in between 0.9 % and 4.8 % positive cases. (Not everyone in close contact will get sick. At highest 1 in 20 with CLOSE CONTACT)
From the same PDF,
As of 20 February, 2114 of the 55,924 laboratory confirmed cases have died (crude fatality ratio [CFR2] 3.8%) (note: at least some of whom were identified using a case definition that included pulmonary disease). The overall CFR varies by location and intensity of transmission (i.e. 5.8% in Wuhan vs. 0.7% in other areas in China).
In China, the overall CFR was higher in the early stages of the outbreak (17.3% for cases with symptom onset from 1-10 January) and has reduced over time to 0.7% for patientswith symptom onset after 1 February (Figure 4). The Joint Mission noted that the standard of care has evolved over the
course of the outbreak.
I feel better, don't you?
(Emphasis mine all mine.)