There has been a vaccine for dogs and cats for a while now, not sure why it hasn't been released for humans yet. Lyme can be really horrible. Some people we know have a 30-something son who was very active (camping, hiking, rock climbing, etc.) until he was bitten by a tick. Now he's quadriplegic.
Lots of drugs work for dogs and cats because they don't live longer than 25yrs. A human has 3-4x the lifespan during which side effects can be worse than the disease.