Before the BCG (TB) vaccine is given, a Heaf test is first administered, often using a stamper tool which makes many small skin punctures to test the immune response. The stamper I received my Heaf test from strongly resembles that pictured in the 5th slide in this presentation.
I'm familiar with how the BCG (TB) vaccine is typically administered with a regular hypodermic syringe injection.
However, when I received my BCG vaccination (at the age of 9) I distinctly remember receiving my vaccination using a the same stamping tool as well, except the cap was red and not yellow. I think I remember the nurse administering the vaccine saying it was an experimental delivery system, but this might be a false memory or corruption. I do not have a BCG scar and apparently I do have some level of TB resistance (according to the second Heaf test I took at the age of 14).
I could not find any information about the BCG vaccine itself being delivered by any kind of stamping tool and I'm curious what exactly happened, and why the stamper isn't used (is it ineffective? is it too expensive? is it not having a scar worth it?)