Spirochaeta pallida: The Microbiology of Syphilis

Abstract

The idea that some human diseases might be caused by the transmission of minute living creatures originated among the myths and legends of the ancient world, and had been seriously suggested by Fracastoro in his On contagion in 1546. Proof that such agents existed had to await the construction of microscopes. The first instruments of good quality were built by the Dutch naturalist Anton von Leeuwenhoek (1632–1723); some of these could magnify objects more than 250 times. The examination of various body fluids revealed many “animalcules” and “infusoria”, but nobody knew what these were or what they meant. A major step was taken by the French microscopist Alexandre Donné (1801–1878), who later became Inspector General of the University of Paris. The design and performance of microscopes was by now much improved, and Donné made some important discoveries, which included blood platelets and the leucocytosis of leukaemia. In 1836 he published his studies “as to the nature of various genito-urinary discharges in both sexes”¹. In specimens from women with vaginitis he had seen many flagellated protozoa:

“The animalcule is of a size double that of a human erythrocyte, or about the size of a pus cell, namely 1140 mm in diameter. The body is round, but may elongate and assume diverse forms. At the anterior end is a long flagellum-like appendage, very thin, which may wave back and forth with great rapidity. On the under part are a number of very fine cilia [later found to be an undulating membrane] that cause a rotating movement. At the posterior end are a number of appendages of uncertain structure.”

If circumstances lead me, I will find where truth is hid

William Shakespeare, Hamlet