Smallpox vaccination techniques; from knives and forks to needles and pins.

Factors affecting the development of smallpox vaccination techniques are discussed and 11 different techniques for inoculating the vaccine are identified and described. The earliest, the simple cut or scratch, was already widely used for smallpox inoculation (variolation). Later, when it became evident that Jenner's claim of lifelong protection was not being achieved parallel, cross-hatched and rotatory methods which produced more severe reactions were introduced, often at more than one site. These methods were then discontinued and even prohibited in some countries, when improved vaccine quality resulted in excessively-severe reactions with such techniques. They were replaced by improved methods such as multiple pressure and multiple puncture with the bifurcated needle, both of which were used extensively. However, the simple scratch method remained popular until the end of the vaccination era. Although the instruments used are not discussed in detail, representative examples of the wide variety used at various times and for the various techniques are illustrated. Again, the simplest and earliest designs remained in use throughout.