Here in Ontario my pup received 3 parvovirus vaccines, the last one at 16 weeks. My vet told me the last one at 12 weeks was probably 97% effective with the final one bringing it up to just over 99%. So we are good to go and have been enjoying our outings. I greatly appreciate everyone who took the time to respond to my queries. I find at my age I have to check for the latest because so much is old info.