Volume 15, Number 12—December 2009
Research
Cost-effectiveness Analysis of Hospital Infection Control Response to an Epidemic Respiratory Virus Threat
Yock Young Dan, Paul A. Tambyah
, Joe Sim, Jeremy Lim, Li Yang Hsu, Wai Leng Chow, Dale A. Fisher, Yue Sie Wong, and Khek Yu Ho
, Joe Sim, Jeremy Lim, Li Yang Hsu, Wai Leng Chow, Dale A. Fisher, Yue Sie Wong, and Khek Yu HoTable 2
Variables used in Markov mode (base case and sensitivity analysis) to compare outbreak estimates, Singapore*
| Variable | Description | Base case | Sensitivity analysis |
|---|---|---|---|
| Exposure | No. persons exposed in 1 day in hospital per index case (nonlinear) | 15 (average for 2 days) 6 (average for 5 days) | 2–30 |
| Secondary attack rate | No. persons exposed/infected | 30% Spanish influenza 10% SARS 30% pandemic (H1N1) 2009 | 10–100% |
| Incubation period | Time to symptoms | Spanish influenza: 2 days SARS: 4 day Pandemic (H1N1) 2009: 3 days | 1–7 |
| Infectious period preclinical | Incubation–latent | Spanish influenza: 1 day SARS: 0 day Pandemic (H1N1) 2009: 1 day | 1–3 |
| % Clinical versus asymptomatic | Spanish influenza: 95% SARS: 100% Pandemic (H1N1) 2009: 95% | 70–100% | |
| % Atypical (missed) | Spanish influenza: 5% SARS: 20% Pandemic (H1N1) 2009: 5% | 0–50% | |
| % Complication | 10× mortality rate | ||
| Infective atypical | Infective | 4 days | 1–7 |
| Case-fatality rate | % death | Spanish influenza: 5% SARS: 10% Pandemic (H1N1) 2009: 4% | |
| Isolation failure | Transmission despite PPE/isolation | 5% | 0–10% |
| Exposure reduction | % reduction in exposure rate | Alert Green 50% Alert Yellow 80% Alert Orange 90% | 0–100% |
| Cost based on alert policy, direct and indirect | Once Daily recurring | Activation: US$110,000 Green: US$4,000 Yellow: US$76,000 Orange: US$100,000 | |
| Cost by type of treatment, based on actual financial charges | Isolation Treatment antiviral/day Uncomplicated influenza Complicated influenza Respiratory failure with mechanical ventilation | US$230 US$25 Mean: US$600, Median: US$420 Mean: US$1800, Median: US$220 Mean: US$5,500, Median:US$4,660 |
*SARS, severe acute respiratory syndrome; PPE, personal protective equipment.
