This a very common question and the answer is a resounding YES! Having worked in the veterinary industry for many years all of our staff have seen pets whose lives could have been saved by vaccination. Parvovirus, leptospirosis, FeLV, cat flu are all devastating diseases that cause enormous suffering to pets and heartbreak for their owners. On the other hand vaccine reactions are extremely few and far between thanks to extensive research. It has been proven that immunity to these diseases decreases after 12 months which is why we vaccinate once per year.