Did Ticks always carry these random awful diseases? If not how did they evolve to have them?

Ticks are a popular topic of discussion nowadays. I remember as a kid, ticks were rare, and when we got them, we just pulled them out and went back to playing. I don't think we even heard of Lyme disease or Alpha Gal syndrome back then.

So why are there so many Ticks now? (Climate change?) And why are they the worst disease carriers on Earth suddenly?