School of Mathematics and Natural Sciences, The University of Southern Mississippi, Hattiesburg, Mississippi, United States
Copyright ©2019, Korea Centers for Disease Control and Prevention
This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
φ1 is the average number of contacts traced per reported case that triggered contact tracing.
φ2is the rate of vaccination and/or isolation of the traced contacts.
ν = φ1 × φ2 ×(1− ζ) is the average number of removal susceptible individuals who were successfully traced/vaccinated/isolated per reported case. The total removal number is in the mass-action form
Conflicts of Interest
No potential conflicts of interest to report that were relevant to this article.
Parameter | Description | All countries | Guinea | Liberia | Sierra Leone | Ref. |
---|---|---|---|---|---|---|
1/α days | incubation period | 11.4 | 10.9 | 11.7 | 10.8 | [2] |
1/γh days | symptom onset to hospitalization | 5 | 5.3 | 4.9 | 4.6 | [2] |
1/γi days | symptom onset to hospital discharge | 16.4 | 16.3 | 15.4 | 17.2 | [2] |
1/γd days | symptom onset to death | 7.5 | 6.4 | 7.9 | 8.6 | [2] |
1/γf days | infectious period between death and burial | 2 | 2 | 2 | 2 | [10] |
θ % | Proportion of infectious cases hospitalized | 54 | 52 | 51 | 58 | [21, 23] |
δ % | Ratio of case-fatality | 70:8 | 70.7 | 72.3 | 69.0 | [2, 17] |
1/γih days | Time from hospitalization to recovery | 11.4 | 11 | 10.5 | 12.6 | Calculation |
1/γdh days | Time from hospitalization to death | 2.5 | 1.1 | 3 | 4 | Calculation |
θ1 % | Fraction of infected hospitalization | 36.8 | 38.2 | 33.9 | 36.1 | Calculation |
δ1 % | Case fatality rate, unhospitalized | 52.6 | 48.7 | 57.3 | 52.7 | Calculation |
δ2 % | Case fatality rate, hospitalized | 34.7 | 19.4 | 42.7 | 41.4 | Calculation |
These epidemiological parameters follow from the study of WHO Ebola Response Team [2, 23] and [10,17]. They are consistent across the modeling literature for different outbreaks.
1/γih = 1/γi − 1/γh, 1/γdh = 1/γd − 1/γh,