We definitely need an effective vaccine for both humans and companion species, but like everything else in applied science there is a risk/benefit decision. I.
Sadly, there was a vaccine out there called Lymerix. But because of some scare of side effect that were later disproven and lack of a market, the manufacturer decided to discontinue it. Oh, and I think some of the scare brought in some lawsuit which didn't help. I think I read that it was 70% effective.
And with the dogs, I used Frontline for years with no problem. When we got a new dog and went to a new Vet, they pushed Advantax. Didn't like the results. Found ticks attached to my dog. So we went back to Frontline and no more ticks.