The reason I ask is because our bodies as human beings have an amazing immune system and unless you have an autoimmune disease, naturally our bodies can heal ourselves from sickness.
I’m speaking primarily on the common cold, Influenza or anything similar like it, including even COVID.
Even if your claim were correct… with every infection the pathogen potentially gets better at infecting humans, and you’re giving it another opportunity to improve and spread to others.
Entire species have been wiped out because natural immunity doesn’t always outpace pathogens’ ability to adapt—letting nature take its course has no predictable winner.