Table 1. Parameters for COVID-19 transmission dynamics in Kathmandu, Nepal.
| Description | Parameter | Value (Range) | Reference |
|---|---|---|---|
| Sampled | |||
| Reproduction number | R0 | 2.4[2.0, 2.8] | Uniform distribution assumed [23, 24] |
| Incubation period (days) | 1/σ | 3[3,7] | Uniform distribution assumed [27] |
| Fixed | |||
| Infectiousness factor for individuals in the exposed compartment | ϵa | 0.1 | Assumption [30] |
| Infectiousness factor for individuals in quarantine | ξQ | 0.3 | Assumption |
| Infectiousness factor for individuals in isolation | ξJ | 0.15 | Assumption |
| Infectiousness duration (days) | 1/γ | 7 | [25] |
| Hospitalization rate among infectious individuals % (age-specific) | u | 2.8 (0−16.6) | [26] |
| Hospitalized patients admitted to ICU % | v | 20 | [31] |
| Infection fatality ratio % (age-specific) | κ | 0.38 (0.0016−7.8) | [26] |
| Proportion of infected individuals quarantined | ϕ1 | 0.1 | Assumption |
| Proportion of infected individuals isolated | ϕ2 | 0.1 | Assumption |
| Average general ward length of stay (days) | 1/δ1 | 8 | Assumption [31] |
| Average ICU length of stay (days) | 1/δ2 | 6 | Assumption [31] |
| Bed capacity (General + ICU) | π | 5400 | [28, 29] |
| Proportion of deaths that occur in the ICU | f | 0.8 | Assumption |
| Dependent on other parameters | |||
| Transmission per day (1/day) | η | 0.34 (0.29−0.4) | Based on R0 and infectious duration* |
| Duration per contact (day) | τ | 0.094 (0.031−0.301) | Based on contact rate* [22] |
| Transmission rate | β | 0.0298 (0.0101−0.0927) | Based on transmissions per day and duration per contact* |
| General ward mortality ratio % (age-specific) | ψ | 2.6 (0.49−9.40 | Based on infection fatality ratio and hospitalization rate* |
| ICU mortality ratio % (age-specific) | ω | 10.2 (1.97−37.59) | Based on infection fatality ratio and ICU admission rate* |
| Excess mortality factor | θ | {0,1.1} | If bed capacity exceeded, 1.1, else 0.*[28, 29] |
Note: Parameter values are based on published estimates and current knowledge about the COVID-19 pandemic. R0 and incubation period are sampled from a uniform distribution to generate uncertainty around model estimates, given possible variability in these parameters. Transmission rate has been calculated based on a Nepal-specific contact matrix. Where appropriate, parameters have been adjusted to Nepal’s age distribution.
*Calculation of dependent parameters is further explained in the S1 Appendix.