[Source: Epidemics, full page: (LINK). Abstract, edited.]
-------
Epidemics. Available online 12 November 2012
Antiviral stockpiles for influenza pandemics from the household perspective: Treatment alone versus treatment with prophylaxis
Antiviral stockpiles for influenza pandemics from the household perspective: Treatment alone versus treatment with prophylaxis
Kin On Kwok<SUP>a</SUP>, Gabriel M. Leung<SUP>a</SUP>, Peter Mak<SUP>a</SUP>, Steven Riley<SUP>a</SUP><SUP>, </SUP><SUP>b</SUP>
<SUP></SUP>
<SUP>a</SUP> Department of Community Medicine and School of Public Health, The University of Hong Kong, 5/F 21 Sassoon Road, Pokfulam, Hong Kong SAR, China; <SUP>b</SUP> MRC Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London
Received 5 June 2012 - Revised 30 October 2012 - Accepted 1 November 2012 - Available online 12 November 2012
http://dx.doi.org/10.1016/j.epidem.2012.11.001
Abstract
Model-based studies of antiviral use to mitigate the impact of moderate and severe influenza pandemics implicitly take the view-point of a central public health authority. However, it seems likely that the key decision of when to use antivirals will be made at the household level. We used a stochastic compartmental model of the transmission of influenza within and between households to evaluate the expected mortality under two strategies: households saving available antivirals for treatment only and households implementing prophylaxis as well as treatment. Given that every individual in the population was allocated a single course of antivirals, we investigated the impact of these two strategies for a wide range of AVE<SUB>D</SUB>, the efficacy of antivirals in preventing death in severe cases (AVE<SUB>D</SUB> = 1 for complete protection). We found a cross-over point for our baseline parameter values in a regime where antivirals were still highly effective in reducing the chance of death: below AVE<SUB>D</SUB> = 0.9 the optimal strategy was for households to use both treatment and prophylaxis. We also considered the possibility that a small number of households might ?cheat? by choosing to follow the treatment-only strategy when other households were following treatment with prophylaxis. The cross-over point for cheating households was considerably lower, at AVE<SUB>D</SUB> = 0.6, but substantially above 0.These results suggest that unless antivirals are almost completely effective in reducing the chance of death in serious cases, households will likely be better served implementing prophylaxis as well as treatment. More generally, our study illustrates the potential value of considering viewpoints other than a central authority when conducting model-based analysis of interventions against infectious disease.
Highlights
► We used a stochastic household compartmental model of the transmission of influenza. ► We compared the impact of treatment only and treatment with prophylaaxis ► We found that unless antivirals were extremely effective in reducing deaths, prophylaxis was justified ► Our results illustrate the importance of household level decisions
Keywords
-<SUP></SUP>
<SUP>a</SUP> Department of Community Medicine and School of Public Health, The University of Hong Kong, 5/F 21 Sassoon Road, Pokfulam, Hong Kong SAR, China; <SUP>b</SUP> MRC Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London
Received 5 June 2012 - Revised 30 October 2012 - Accepted 1 November 2012 - Available online 12 November 2012
http://dx.doi.org/10.1016/j.epidem.2012.11.001
Abstract
Model-based studies of antiviral use to mitigate the impact of moderate and severe influenza pandemics implicitly take the view-point of a central public health authority. However, it seems likely that the key decision of when to use antivirals will be made at the household level. We used a stochastic compartmental model of the transmission of influenza within and between households to evaluate the expected mortality under two strategies: households saving available antivirals for treatment only and households implementing prophylaxis as well as treatment. Given that every individual in the population was allocated a single course of antivirals, we investigated the impact of these two strategies for a wide range of AVE<SUB>D</SUB>, the efficacy of antivirals in preventing death in severe cases (AVE<SUB>D</SUB> = 1 for complete protection). We found a cross-over point for our baseline parameter values in a regime where antivirals were still highly effective in reducing the chance of death: below AVE<SUB>D</SUB> = 0.9 the optimal strategy was for households to use both treatment and prophylaxis. We also considered the possibility that a small number of households might ?cheat? by choosing to follow the treatment-only strategy when other households were following treatment with prophylaxis. The cross-over point for cheating households was considerably lower, at AVE<SUB>D</SUB> = 0.6, but substantially above 0.These results suggest that unless antivirals are almost completely effective in reducing the chance of death in serious cases, households will likely be better served implementing prophylaxis as well as treatment. More generally, our study illustrates the potential value of considering viewpoints other than a central authority when conducting model-based analysis of interventions against infectious disease.
Highlights
► We used a stochastic household compartmental model of the transmission of influenza. ► We compared the impact of treatment only and treatment with prophylaaxis ► We found that unless antivirals were extremely effective in reducing deaths, prophylaxis was justified ► Our results illustrate the importance of household level decisions
Keywords
- Pandemic influenza (pandemic flu);
- Treatment;
- Prophylaxis;
- Anti-viral drugs;
- Mathematical models
-------