> If it is the latter, an answer I can't find anywhere, why did we need to waste so much time developing a vaccine? Wouldn't it be equally efficacious to introd

> If it is the latter, an answer I can't find anywhere, why did we need to waste so much time developing a vaccine? Wouldn't it be equally efficacious to introduce one virus to the body on day one, four on day two, and so on until immunity is achieved? Introducing the virus like this, you’ve created a live virus vaccine. The work involved in creating and testing such a vaccine isn’t really any less than creating the vaccines we did make. You still have to develop technology to grow the virus and distribute exactly the right quantity. Moreover, the risk of complications is far greater if someone fails to fight off the small viral load infection. The vaccines such as Moderna only took a week or two to prototype in January 2020. The entire rest of the time was scaling up production and running tests to prove it worked in the population. We could have skipped running the trials and deployed the untested vaccine instead. A lot of lives would have been saved but no way to know that without doing the trials, I suppose.