shaped the opinion of many in the public health and health care communities, and created confusion in the mass media.
Within several weeks of the beginning of the vaccination program across the nation, the mass media reported a halting start (slow in comparison with the pace suggested by the initial 30-day timeline) as prospective vaccinees weighed substantial unknowns against what they knew about potential vaccine complications and in the absence of an adequate compensation plan (Bavley and Dvorak, 2003; GAO, 2003; Kemper, 2003; McCullough, 2003; Ornstein and Bonilla, 2003). The vaccination rate dropped steeply in April and May 2003 in the wake of cardiac adverse events and the announced end of major combat in Iraq. As DHHS and CDC officials were questioned about the number of vaccinees necessary for preparedness, the figure of 50,000 was offered although no additional guidance was made available to advise states on the numbers they would need to “effectively investigate an outbreak, care for patients, and vaccinate members of the public”, especially given the variation among states and the difference between the number achieved and initial estimates (GAO, 2003). The value and legitimacy of the vaccination program were further questioned in news reports that documented shifting goals and CDC’s often uneasy communication on the matter, for example, a change in the DHHS-CDC position on the numbers of vaccinees, denial that there had been a change in the program’s focus, and the claim that preparedness, not numbers of vaccinees, had been the focus all along (Roos, 2003; Shockman, 2003). Public health officials even expressed some concern that they might have inadvertently created an exaggerated perception of the risk posed by the vaccine by being exceedingly cautious in informing prospective vaccinees about possible complications (Connolly, 2003a).
In a program already beset by ambiguity and unanswered questions, numbers seemed to constitute one concrete element, but the lack of an explanation of the scientific evidence and public health reasoning that went into shaping the smallpox vaccination program left the numbers—and the expectations of key actors, the mass media, and the public—ungrounded in factual information. Because preparedness was not defined from the beginning and the concept of broad preparedness was not reiterated and reinforced during the course of the program, numbers, however inexact, became a proxy for preparedness. The lack of clarification of the relationship between vaccination and preparedness allowed vaccination to obscure and even supersede comprehensive preparedness in rhetoric and in practice. Little or no explanation or evidence was provided to explain whether preparedness was related to vaccination; whether vaccination was required for preparedness and, if so, what number of vaccinees; and what constitutes preparedness. In fact, some of the early communication from CDC implied that preparedness required vaccination and that rapid vacci-