Even under the lower cost of USD$6.6, long term stockpiling strategies were cost-beneficial only with high vaccine effectiveness of >60% or high attack rates of >40%.
For long term stockpiling strategies with 1957 and 1968 pandemic case-fatality rates of 0.4 to 0.6%, stockpiling would be cost-beneficial only if the pandemic occurred within 10 years, the shelf-life was 5 years, and vaccine effectiveness was >80%.
The input parameters for analysis (Table 1) were obtained from local sources when available as detailed in a previous study on stockpiling strategies in Singapore (2 ).
Because of the potentially important implications of our findings for public health and stockpiling strategies, and because of the apparent discrepancy with the results of Hurt et al. (6 ), we retested 2 viruses from each group against an independent source of oseltamivir carboxylate (provided by Biota, Notting Hill, Victoria, Australia).
Rather than stockpiling, another strategy needs to be considered for vaccines containing a virus such as A (H5N1) for which vaccine development has already begun.
For the smallest stockpiles, the best strategy was to treat conventional influenza at-risk groups.
While highlighting the importance of management of drug-resistance in the population, these simulations indicate that for small stockpiles, adaptive antiviral strategy has no significant benefits over a constant treatment policy.
Therefore, the strategy of stockpiling influenza NA antivirals as a first line of defense against new pandemic strains could be endangered.
For example, a pre-pandemic strategy involves stockpiling vaccine matched to prevalent avian-origin H5N1 viruses based on global surveillance, to be deployed during a pandemic alert or at the start of the pandemic, which can be followed by a booster dose of vaccine matched to the actual emerging strain given when batches become available [ 6, 7].
Entering Saturday's auction in mixed-league Tout Wars, an elite industry competition, I was primed to use a "stars and scrubs" strategy to stockpile the strongest bats and take advantage of the excellent depth in the pitching pool on the cheap.
