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Published online by Cambridge University Press: 24 August 2009

* In response to our inquiry about the certainty of this, Professor Fenner explained (in litt. 10 July 1980): ‘Smallpox is a disease, and the disease has been eradicated, even though the virus is still preserved in a few laboratories.’—Ed.
* See top footnote on page 173 and the WHO account following it; also footnote on page 177.—Ed.