You know, I've thought this before, but have no real evidence. I never heard of so many dogs having seizures. My ex-boss's black lab had a seizure the day after he was vaccinated. My grandson actually had a seizure (for no reason they can find) the day after he had his booster shots at the doctors. These are the cases I'm directly related to, but have heard of many more, people and animals. It seems like too much coincidence to me.