[jp4m2]

You can use a titer test about two weeks after vaccination to determine if the vaccination was effective in stimulating an immune response (in other words, if the animal was successfully immunized from the vaccine), but testing that same animal's titer years down the road doesn't really tell you anything new, because immunity to specific viruses is reliant not on antibodies, but on memory cells, which we have no way to measure. Memory cells are what prompt the immune system to create antibodies and dispatch them to an infection caused by the virus it "remembers." Memory cells don't need "reminders" in the form of re-vaccination to keep producing antibodies.

Since some people get nervous stopping vaccines after puppy shots, they will get a booster at approx. 1 year of age for a distemper and parvo vaccine. As you can see at 12 weeks, 10% of pups wil lstill have natural immunity remaining so the vaccine will not produce a strong response so as to why the nervous ones will do the one year booster.....

Research shows that less than 50% of puppies will respond at 6 wks. of age. 75% at 9 wks. of age; 90% at 12 weeks; and by 14 to16 weeks, close to 100% will respond. “(In the August 2008 issue of The Whole Dog Journal, Dr. Ronald Schultz)