Alternative vaccine delivery methods

The cutaneous route for such variolation involved breaking the skin with a sharp instrument, and it was used in India perhaps as early as in China, but it was not documented until the 16th century. 2 Variolation was supplanted by safer cutaneous application of material from cowpox lesions, the method of “vaccination” known in the 18th century and first published by Edward Jenner. After 15th-century experiments with hypodermic injection, 3