I looked on Wiki, and there isn't much there.
A mention of a human vaccine improvement in the mid 60's.
You can Google for more if it is important to you.
But the vaccine had been around for years before then and required 21 shots in the abdomen which were painful and had loads of side effects.
__________________
All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
************************************
.
Weezie looking at petunias 8.25.2017
****************************
These forums are for mutual support and information sharing only. The forums are not a substitute for medical advice, diagnosis or treatment provided by a qualified health care provider. Always consult your doctor before trying anything you read here.