So that this... these articles appearing in Science magazine laid the groundwork for this enormous controversy, and that is whether it's safe to use normal human cells for vaccine production. And as I said, we ultimately triumphed in respect to the fact that WI-38, a subsequent cell strain, MRC-5, and maybe one or two more, have been used for... have been used for the production of human virus vaccines. WI-38 and MRC-5 together have been used for the production of vaccines that have been used in over 2 billion people on the... planet, approximately a quarter of the total world's population, without any evidence of a side effect attributable to the cells themselves. I don't think that I can say it in more certain terms.

The... I also should say, parenthetically – and this is very important, as I will soon describe – that WI-38, at that time in 1962, which is when that particular strain succeeded, WI-26 and became more widespread in its use... that WI-38 could not be patented, despite our efforts to do so, because the patent laws in the United States and I believe in most other countries did not allow for the patenting of living materials, other than particular kinds of decorative plants and fruit bearing trees that were allowed to be patented. So, that when we went through the efforts of trying to patent these cells, knowing that this was going to be a serious problem, we failed.

Consequently, I delivered ampoules of WI-38 worldwide gratis to every... virtually every virus vaccine manufacturer in the world; I mean Russia, Japan, Europe, United States, all the major vaccine manufacturers... and Yugoslavia, I should say, whose director will come into play in... later on in this story.