From "Expected Adverse Events in a Mass Smallpox Vaccination Campaign" Effective Clinical Practice, March/April 2002. 5:84-90.

Figure 2. Effect of exclusion criteria on overall vaccination uptake. The white circles indicate high-risk individuals with eczema or immunocompromised individuals, who would never be vaccinated. The eccentric circles illustrate the effect of more or less restrictive exclusion criteria of potential contacts of high-risk individuals on the overall number of Americans vaccinated. The remaining area within the square represents the proportion of the U.S. population who could be vaccinated.
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