Table 2 Estimates of model parameters for the COVID-19 outbreak within mainland China.

τ_β

Time point when the transmission rate is estimated to change because of control measures

U[60,143]*

70.6 (69.2,71.9)

71.4 (70.2,72.0)

β_a

Daily transmission rate before τ_β

U[0.020,1.00]

0.523 (0.311,0.691)

0.512 (0.292,0.674)

β_b

Daily trasnmission rate after τ_β

U[0.001,0.20]

0.009 (0.001,0.031)

0.007 (0.001,0.031)

R_0,1

Reproduction number before τ_β

–

2.33 (1.96,3.69)

2.20 (1.85,4.10)

R_{0_con}

R₀ due to confirmed cases before τ_β

–

0.042 (0.017,0.111)

0.037 (0.013,0.107)

R_{0_und}

R₀ due to undetected cases before τ_β

–

2.27 (1.92,3.65)

2.16 (182,4.07)

R_0,2

Reproduction number after τ_β

–

0.036 (0.006,0.100)

0.027 (0.006,0.094)

I₀

Initial number of infectious people on 1/12/2019

U[1,500]

8.7 (2.7,49.1)

14.3 (2.4,67.8)

Initial total number of people infected with the virus on 1/12/2019

–

40.9 (12.8,207.2)

71.1 (12.4,304.4)

τ_θ

Time point when the case ascertainment rate is estimated to change

U[40,62]*

49.3 (47.1,51.6)

50.1 (48.0,52.8)

θ_1,a

Case ascertainment rate before τ_θ

U[1%,25%]

3.48% (1.74%,8.33%)

3.47% (1.35%,8.96%)

θ_1,b

Case ascertainment rate after τ_θ

U[25%,100%]

36.61% (26.07%,55.39%)

38.29% (30.44%,55.67%)

τ_F

Time point when the confirmed case-fatality rate (cCFR) is estimated to change

U[65,95]*

77.0 (75.3,78.0)

77.4 (76.0,78.9)

θ_2,a

Mortality rate among confirmed cases (cCFR₁) before τ_F

U[0.5%,50%]

9.61% (8.12%,11.36%)

8.56% (7.51%,10.01%)

θ_2,b

Mortality rate among confirmed cases (cCFR₂) after τ_F

U[0.1%,50%]

0.67% (0.45%,0.97%)

1.28% (0.96%,2.35%)

D₁

Average infectious period before hospitalization (days)

U[2.0,10]

2.28 (2.01,3.12)

2.12 (2.0,2.71)

D₁+D_u

Average infectious period of undetected infections (days)

U[3.0,25.0]

4.44 (3.19,11.71)

4.31 (3.11,13.43)

η^HOS

Dispersion parameter for reported cases

U[1.01,1500]

76.0 (50.2,122.8)

82.8 (53.9,134.1)

η^Death

Dispersion parameter for deaths

U[1.01,5000]

3.5 (2.4,5.2)

4.0 (2.8,5.9)

η^Recovery

Dispersion parameter for recoveries

U[1.01,1500]

144.8 (102.8,205.6)

150.3 (104.7,215.37)

IFR₁

Infection fatality rate (θ_1,aθ_2,a) before τ_θ

–

0.33% (0.17%,0.85%)

0.30% (0.11%,0.81%)

IFR₂

Infection fatality rate (θ_1,bθ_2,a) between τ_θ and τ_F

–

3.51% (2.60%,5.12%)

3.31% (2.47%,4.89%)

IFR₃

Infection fatality rate (IRF₂ = θ_1,bθ_2,b) after τ_F

–

0.24% (0.15%,0.41%)

0.50% (0.34%,0.86%)