Desk 1. Parameter Values that change among the many 5 COVID-19 Pandemic Planning Eventualities. The situations are supposed to advance public well being preparedness and planning. They’re not predictions or estimates of the anticipated influence of COVID-19. The parameter values in every situation will likely be up to date and augmented over time, as we study extra in regards to the epidemiology of COVID-19. Further parameter values may be added sooner or later (e.g., inhabitants density, family transmission, and/or race and ethnicity).
|Parameter||Situation 1||Situation 2||Situation 3||Situation 4||Situation 5: Present Greatest Estimate|
|An infection Fatality Ratio†||0-19 years: 0.00002
20-49 years: 0.00007
50-69 years: 0.0025
70+ years: 0.028
|0-19 years: 0.0001
20-49 years: 0.0003
50-69 years: 0.010
70+ years: 0.093
|0-19 years: 0.00003
20-49 years: 0.0002
50-69 years: 0.005
70+ years: 0.054
|% of infections which can be asymptomatic§||10%||70%||10%||70%||40%|
|Infectiousness of asymptomatic people relative to symptomatic¶||25%||100%||25%||100%||75%|
|Proportion of transmission occurring previous to symptom onset**||30%||70%||30%||70%||50%|
Chinazzi M, Davis JT, Ajelli M, et al. The impact of journey restrictions on the unfold of the 2019 novel coronavirus (COVID-19) outbreak. Science. 2020;368(6489):395-400; Imai N., Cori, A., Dorigatti, I., Baguelin, M., Donnelly, C. A., Riley, S., Ferguson, N.M. (2020). Report 3: Transmissibility of 2019-nCoV. On-line report
Li Q, Guan X, Wu P, et al. Early Transmission Dynamics in Wuhan, China, of Novel Coronavirus-Contaminated Pneumonia. N Engl J Med. 2020;382(13):1199-1207
Munayco CV, Tariq A, Rothenberg R, et al. Early transmission dynamics of COVID-19 in a southern hemisphere setting: Lima-Peru: February Twenty ninth-March thirtieth, 2020 [published online ahead of print, 2020 May 12]. Infect Dis Mannequin. 2020; 5:338-345
Salje H, Tran Kiem C, Lefrancq N, et al. Estimating the burden of SARS-CoV-2 in France [published online ahead of print, 2020 May 13] [published correction appears in Science. 2020 Jun 26;368(6498):]. Science. 2020;eabc3517.
The vary of estimates for Eventualities 1-4 characterize the higher and decrease sure of the widest confidence interval estimates reported in: Li Q, Guan X, Wu P, et al. Early Transmission Dynamics in Wuhan, China, of Novel Coronavirus-Contaminated Pneumonia. N Engl J Med. 2020;382(13):1199-1207.
Substantial uncertainty stays across the R0 estimate. Notably, Sanche S, Lin YT, Xu C, Romero-Severson E, Hengartner N, Ke R. Excessive Contagiousness and Fast Unfold of Extreme Acute Respiratory Syndrome Coronavirus 2. Emerg Infect Dis. 2020;26(7):1470-1477 (https://dx.doi.org/10.3201/eid2607.200282exterior icon) estimated a median R0 worth of 5.7 in Wuhan, China. In an evaluation of 8 Europe international locations and the US, the identical group estimated R0 of between 4.0 and seven.1 within the pre-print manuscript: Ke R., Sanche S., Romero-Severson, & E., Hengartner, N. (2020). Quick unfold of COVID-19 in Europe and the US suggests the need of early, robust and complete interventions. medRxiv.
† These estimates are primarily based on age-specific estimates of an infection fatality ratios from Hauser, A., Counotte, M.J., Margossian, C.C., Konstantinoudis, G., Low, N., Althaus, C.L. and Riou, J., 2020. Estimation of SARS-CoV-2 mortality through the early phases of an epidemic: a modeling examine in Hubei, China, and 6 areas in Europe. PLoS drugs, 17(7), p.e1003189. Hauser et al. produced estimates of IFR for 10-year age bands from 0 to 80+ yr previous for six areas in Europe. Estimates exclude an infection fatality ratios from Hubei, China, as a result of we assumed an infection and case ascertainment from the 6 European areas usually tend to mirror ascertainment within the U.S. To acquire one of the best estimate values, the purpose estimates of IFR by age had been averaged to broader age teams for every of the 6 European areas utilizing weights primarily based on the age distribution of reported instances from COVID-19 Case Surveillance Public Use Knowledge (https://information.cdc.gov/Case-Surveillance/COVID-19-Case-Surveillance-Public-Use-Knowledge/vbim-akqf). The estimates for individuals ≥70 years previous offered right here don’t embody individuals ≥80 years previous as IFR estimates from Hauser et al., assumed that 100% of infections amongst individuals ≥80 years previous had been reported. The consolidated age estimates had been then averaged throughout the 6 European areas. The decrease sure estimate is the bottom, non-zero level estimate throughout the six areas, whereas the higher sure is the best level estimate throughout the six areas.
§ The % of instances which can be asymptomatic, i.e. by no means expertise signs, stays unsure. Longitudinal testing of people is required to precisely detect the absence of signs for the complete interval of infectiousness. Present peer-reviewed and preprint research differ broadly in follow-up instances for re-testing, or don’t embody re-testing of instances. Moreover, research differ within the definition of a symptomatic case, which makes it tough to make direct comparisons between estimates. Moreover, the % of instances which can be asymptomatic might differ by age, and the age teams reported in research differ. Given these limitations, the vary of estimates for Eventualities 1-4 is large. The decrease sure estimate approximates the decrease 95% confidence interval sure estimated from: Byambasuren, O., Cardona, M., Bell, Ok., Clark, J., McLaws, M. L., & Glasziou, P. (2020). Estimating the extent of true asymptomatic COVID-19 and its potential for neighborhood transmission: systematic assessment and meta-analysis. Out there at SSRN 3586675. The higher sure estimate approximates the higher 95% confidence interval sure estimated from: Poletti, P., Tirani, M., Cereda, D., Trentini, F., Guzzetta, G., Sabatino, G., Marziano, V., Castrofino, A., Grosso, F., Del Castillo, G. and Piccarreta, R. (2020). Chance of signs and significant illness after SARS-CoV-2 an infection. arXiv preprint arXiv:2006.08471. The most effective estimate is the midpoint of this vary and aligns with estimates from: Oran DP, Topol EJ. Prevalence of Asymptomatic SARS-CoV-2 An infection: A Narrative Assessment [published online ahead of print, 2020 Jun 3]. Ann Intern Med. 2020; M20-3012.
¶ The present greatest estimate relies on a number of assumptions. The relative infectiousness of asymptomatic instances to symptomatic instances stays extremely unsure, as asymptomatic instances are tough to establish, and transmission is tough to watch and quantify. The estimates for relative infectiousness are assumptions primarily based on research of viral shedding dynamics. The higher sure of this estimate displays research which have proven related durations and quantities of viral shedding between symptomatic and asymptomatic instances: Lee, S., Kim, T., Lee, E., Lee, C., Kim, H., Rhee, H., Park, S.Y., Son, H.J., Yu, S., Park, J.W. and Choo, E.J., Medical Course and Molecular Viral Shedding Amongst Asymptomatic and Symptomatic Sufferers With SARS-CoV-2 An infection in a Neighborhood Therapy Middle within the Republic of Korea. JAMA Inside Drugs; Zou L, Ruan F, Huang M, et al. SARS-CoV-2 Viral Load in Higher Respiratory Specimens of Contaminated Sufferers. N Engl J Med. 2020;382(12):1177-1179; and Zhou R, Li F, Chen F, et al. Viral dynamics in asymptomatic sufferers with COVID-19. Int J Infect Dis. 2020; 96:288-290. The decrease sure of this estimate displays information indicating that viral masses are larger in extreme instances relative to gentle instances (Liu Y, Yan LM, Wan L, et al. Viral dynamics in gentle and extreme instances of COVID-19. Lancet Infect Dis. 2020;20(6):656-657) and information exhibiting that viral masses and shedding durations are larger amongst symptomatic instances relative to asymptomatic instances (Noh JY, Yoon JG, Seong H, et al. Asymptomatic an infection and atypical manifestations of COVID-19: Comparability of viral shedding period [published online ahead of print, 2020 May 21]. J Infect. 2020; S0163-4453(20)30310-8).
** The decrease sure of this parameter is approximated from the decrease 95% confidence interval sure from: He, X., Lau, E.H., Wu, P., Deng, X., Wang, J., Hao, X., Lau, Y.C., Wong, J.Y., Guan, Y., Tan, X. and Mo, X. (2020). Temporal dynamics in viral shedding and transmissibility of COVID-19. Nature drugs, 26(5), pp.672-675. The higher sure of this parameter is approximated from the upper estimates of particular person research included in: Casey, M., Griffin, J., McAloon, C.G., Byrne, A.W., Madden, J.M., McEvoy, D., Collins, A.B., Hunt, Ok., Barber, A., Butler, F. and Lane, E.A. (2020). Estimating pre-symptomatic transmission of COVID-19: a secondary evaluation utilizing printed information. medRxiv.The most effective estimate is the geometric imply of the purpose estimates from these two research.
Desk 2. Parameter Values Frequent to the 5 COVID-19 Pandemic Planning Eventualities. The parameter values are more likely to change as we acquire extra information about illness severity and viral transmissibility of COVID-19.
Parameter values are primarily based on information acquired by CDC via August 8, 2020, together with COVID-19 Case Surveillance Public Use Knowledge (https://information.cdc.gov/Case-Surveillance/COVID-19-Case-Surveillance-Public-Use-Knowledge/vbim-akqf); information from the Hospitalization Surveillance Community (COVID-NET) (via August 1); and information from Knowledge Collation and Integration for Public Well being Occasion Response (DCIPHER).
Assumption, ASPR and CDC
|No pre-existing immunity earlier than the pandemic started in 2019. It’s assumed that each one members of the U.S. inhabitants had been inclined to an infection previous to the pandemic.|
|Time from publicity to symptom onset*||~6 days (imply)|
|Time from symptom onset in a person and symptom onset of a second particular person contaminated by that particular person†||~6 days (imply)|
|Imply ratio of estimated infections to reported case counts, Total (vary)§||11 (6, 24)|
|Parameter Values Associated to Healthcare Utilization|
|Median variety of days from symptom onset to SARS-CoV-2 take a look at amongst SARS-CoV-2 constructive sufferers (interquartile vary)¶||
Total: 3 (1, 6) days
|Median variety of days from symptom onset to hospitalization (interquartile vary)**||
18-49 years: 6 (3, 10) days
50-64 years: 6 (2, 10) days
≥65 years: 4 (1, 9) days
|Median variety of days of hospitalization amongst these not admitted to ICU (interquartile vary) ††||
18-49 years: 3 (2, 5) days
50-64 years: 4 (2, 7) days
≥65 years: 6 (3, 10) days
|Median variety of days of hospitalization amongst these admitted to ICU (interquartile vary)††,§§||
18-49 years: 11 (6, 20) days
50-64 years: 14 (8, 25) days
≥65 years: 12 (6, 20) days
|% admitted to ICU amongst these hospitalized††||
18-49 years: 23.8%
50-64 years: 36.1%
≥65 years: 35.3%
|% on mechanical air flow amongst these hospitalized. Contains each non-ICU and ICU admissions††||
18-49 years: 12.0%
50-64 years: 22.1%
≥65 years: 21.1%
|% that die amongst these hospitalized. Contains each non-ICU and ICU admissions††||
18-49 years: 2.4%
50-64 years: 10.0%
≥65 years: 26.6%
|Median variety of days of mechanical air flow (interquartile vary)**||
Total: 6 (2, 12) days
|Median variety of days from symptom onset to dying (interquartile vary)**||
18-49 years: 15 (9, 25) days
50-64 years: 17 (10, 26) days
≥65 years: 13 (8, 21) days
|Median variety of days from dying to reporting (interquartile vary)¶¶||
18-49 years: 19 (5, 45) days
50-64 years: 21 (6, 46) days
≥65 years: 19 (5, 44) days
* McAloon, C.G., Collins, A., Hunt, Ok., Barber, A., Byrne, A., Butler, F., Casey, M., Griffin, J.M., Lane, E., McEvoy, D. and Wall, P. (2020). The incubation interval of COVID-19: A speedy systematic assessment and meta-analysis of observational analysis. medRxiv.
† He, X., Lau, E.H., Wu, P., Deng, X., Wang, J., Hao, X., Lau, Y.C., Wong, J.Y., Guan, Y., Tan, X. and Mo, X. (2020). Temporal dynamics in viral shedding and transmissibility of COVID-19. Nature drugs, 26(5), pp.672-675.
§ The purpose estimate is the geometric imply of the placement particular level estimates of the ratio of estimated infections to reported instances, from Havers, F.P., Reed, C., Lim, T., Montgomery, J.M., Klena, J.D., Corridor, A.J., Fry, A.M., Cannon, D.L., Chiang, C.F., Gibbons, A. and Krapiunaya, I., 2020. Seroprevalence of antibodies to SARS-CoV-2 in 10 websites in america, March 23-Could 12, 2020. JAMA Inside Drugs. The decrease and higher bounds for this parameter estimate are the bottom and highest level estimates of the ratio of estimated infections to reported instances, respectively, from Havers et al., 2020.
¶ Estimates solely embody symptom onset dates between March 1, 2020 – July 15, 2020. Estimates characterize time to acquire SARS-CoV-2 exams amongst instances who examined constructive for SARS-CoV-2. Estimates primarily based on and information from Knowledge Collation and Integration for Public Well being Occasion Response (DCIPHER).
** Estimates solely embody symptom onset dates between March 1, 2020 – July 15, 2020 to make sure instances have had adequate time to watch the result (hospital discharge or dying). Knowledge for 17 yr olds and below are suppressed as a consequence of small pattern sizes.
†† Primarily based on information reported to COVID-NET by Aug 1, 2020. Knowledge for 17 yr olds and below are suppressed as a consequence of small pattern sizes. https://gis.cdc.gov/grasp/COVIDNet/COVID19_5.html.
§§ Cumulative size of keep for individuals admitted to the ICU, inclusive of each ICU and non-ICU days.
¶¶ Estimates solely embody dying dates between March 1, 2020 – July 15, 2020 to make sure adequate time for reporting. Knowledge for 17 yr olds and below are suppressed as a consequence of small pattern sizes.