Science marches on, improving over time. We know that. It's still weird to watch it improve, and realize that you now come from an era of outdated science.
Not too long ago I started a volunteer job that required me to work with the public. Before I could start, the organization wanted to make sure that I wasn't a walking bundle of contagion. They asked me to make sure I was current on my immunizations and to get a tuberculosis test. I did, and to save you any suspense or concern, I'll announce straight away that I don't appear to have tuberculosis. So that's a lucky break.
What interested me was the fact that the test consisted of a slender needle that injected a substance under my skin. I told the person doing the injection that the last tuberculosis test I'd had was at school, where I'd had a "four pronged thing" pushed against my arm like a stamp. It was like I'd told her that they'd tested me by burning sage and dangling a lodestone over my belly. "Oh, wow," she said, "that's completely obsolete. I've never even used that test."
Frankly, I think she was being overdramatic. The underlying principle of both tests are the same. Scientists noticed that, once an animal was injected with a vaccine, the second injection of the same vaccine produced a localized allergic reaction. The area around the injection site got red and swollen. When a scientist named Robert Koch extracted harmless protein from the tuberculosis bacterium, people realized that they could use the protein the same way they would a second dose of vaccine. If a person had already been exposed to the bacterium, the area around an injection site would flair up.
My retro four-pronged test was called the Tine Test. The small prongs were covered in tuberculin, the extracted protein, and pushed just under the skin. It was quick, but it didn't always deliver the amount of tuberculin needed to get a reaction, and so turned up false negatives. One study showed that out of forty-one tests, the Tine Test missed nine positives. The Mantoux Test, which is what the syringe test is called, injected a set amount of the substance and helped doctors make sure they didn't miss anything.
Which is all well and good, but it did give me a little surprise. Being mostly healthy all my life, I've never really had to keep up with changing medical technology. This is the first time any medical procedure done on me has changed - radically, going by the lab tech's expression - during my lifetime. I assume it's going to happen again, but it makes me curious. Has anyone been surprised by how medicine has changed over the course of your life? Have you reaped the benefit of any major changes?