I have temporarily withdrawn this page as much of its content is the substance of a new article that is currently submitted and under review. Anyone wishing to see the substance of this can email me and ask to preview it. This will be on the understanding that it will not be circulated further.

This article has now been accepted for publication in the Scandinavian Journal of Immunology. See "Published" folder under "A proliferation of pathogens through the 20th Century".