New England Journal of Medicine
Volume 361 — July 9, 2009 — Number 2
http://content.nejm.org/current.shtml

Perspective
Managing and Reducing Uncertainty in an Emerging Influenza Pandemic
M. Lipsitch and Others

[First 110 words per NEJM convention]
The early phases of an epidemic present decision makers with predictable challenges1 that have been evident as the current novel influenza A (H1N1) virus has spread. The scale of the problem is uncertain when a disease first appears but may increase rapidly. Early action is required, but decisions about action must be made when the threat is only modest — and consequently, they involve a trade-off between the comparatively small, but nearly certain, harm that an intervention may cause (such as rare adverse events from large-scale vaccination or economic and social costs from school dismissals) and the uncertain probability of . .