Infectious disease outbreaks sometimes overwhelm healthcare facilities. A recent case occurred in West Africa in 2014 when an Ebola virus outbreak overwhelmed facilities in Sierra Leone, Guinea and Liberia. In such scenarios, how many patients can hospitals admit to minimize disease burden? This study considers what type of hospital admission policy during a hypothetical Ebola outbreak can better serve the community, if overcrowding degrades the hospital setting. Our result shows that which policy minimizes loss to the community depends on the initial estimation of the control reproduction number, $R_0$. When the outbreak grows extremely fast ($R_0$$ \gg $1) it is better (in terms of total disease burden) to stop admitting patients after reaching the carrying capacity because overcrowding in the hospital makes the hospital setting ineffective at containing infection, but when the outbreak grows only a little faster than the system's ability to contain it ($R_0 \gtrsim 1$), it is better to admit patients beyond the carrying capacity because limited overcrowding still reduces infection more in the community. However, when $R_0$ is no more than a little greater than 1 (for our parameter values, 1.012), both policies result the same because the number of patients never exceeds the maximum capacity.
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Table 1.
Estimation of the parameter
Table 2. Model parameters and their values
Parameter | Meaning | Value |
Infection rate in the community | 0.455/day | |
Infection rate in the hospital | 0.004375 /person-day | |
Recovery rate in the community | 0.04/day | |
Recovery rate in the hospital | 0.057/day | |
Death rate in the community | 0.172/day | |
Death rate in the hospital | 0.102/day | |
Patients transfer rate from community to hospital | 0.184/day | |
Recovery rate in the hospital from primary diseases | 0.067/day | |
Carrying capacity of the hospital | 40 beds | |
Scaling parameter for deterio- ration of the hospital setting under overcrowded scenario | 0.48067 |
Table 3. Summary of the epidemic for both policies: Continue to admit patients (policy Ⅰ) or limit admissions to the carrying capacity (policy Ⅱ)
Policy | Infections | Deaths | Uninfected |
Ⅰ | 98, 486 | 79, 844 | 1514 |
Ⅱ | 98, 518 | 79, 827 | 1482 |
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