When I lived in NZ, my dogs got their 3 puppy vax's and that was it. When we went away they could stay at a mates so didn't need vax's for kennels. 2 of my dogs only had one puppy vax at about 10 weeks and I didnt bother with the rest. 1 dog had all 3 and then got parvo a few weeks after her last one (she survived but did only get a minor dose of it).
So out of those 3 dogs, only the one at the time who who fully vax'd contracted parvo (she was the first dog I had out of home and that was the reason I stopped giving vaxs).
I would take the dogs EVERYWHERE. They often met other dogs. One of our favourite placs to go I later found out was a parvo mine field (this was after the one got parvo) and none of them got it (except for the one small bout which wasnt contracted at that park).
I also had 3 cats who never even had their kitten vaxs.
Chev (the one who had all 3 pup vaxs and got parvo) had her next vaccination at 12 years old and only because we wer emoving to Oz and it was a condition of import/export. Barney also had a shot, he was 5 and had only had one puppy one at 10 weeks.
My mother never vax's either though like me, will sometimes give the puppy shots. IMO they build their own immunity depending on the way they are exposed.
Currently my dogs are on yearly boosters, but the main reason for that is because if we go away they need to be in a kennel and they need to be vaxd. However, Barney was due for his booster in Jun 11 and Pippi was due in September 11 and neither of them have had them. I am not fussed.
In regards to the other, they are wormed every 3 months, have heartworm treatment every month (we dont get this in NZ at all so its a bit scary for me) and they have flea and tick treatment every 2 weeks (we dont get paralysis ticks either and they scare me a bit too)