diggy4,
You are so fortunate, it sounds like you have a very good veterinarian for Bella! The information below, along with your veterinarian's input, may help you in making a decision about titers and booster vaccinations for Bella.
This is what Dr. Ronald Schultz had to say in his 2007 presentation to the AKC Canine Health Foundation entitled,
What Everyone Needs to Know About Canine Vaccines and Vaccination Programs http://www.puliclub.org/CHF/AKC2007C...20Vaccines.htm :
"An antibody titer no matter how low shows the animal has immunologic memory since memory effector B cells must be present to produce that antibody. Some dogs without antibody are protected from disease because they have T cell memory, that will provide cell mediated immunity (CMI). CMI will not protect from reinfection, but it will prevent disease."
"My own dogs, those of my children and grandchildren are vaccinated with MLV CDV, CPV-2, CPI, andCAV-2 vaccines once as puppies after the age of 12 weeks. An antibody titer is performed two or more weeks later and if found positive our dogs are never again vaccinated. " he further elaborates:
"I have used this vaccination program with modifications (CAV-2 replaced CAV-1 vaccines in 1970's and CPV-2 vaccines were first used in 1980) since 1974! I have never had one of our dogs develop CDV, CAV-1 or CPV-2 even though they have had exposure to many dogs, wildlife and to virulent CPV-2 virus. You may say that I have been lucky, but it is not luck that protects my dogs, it is immunologic memory."
The live polio vaccine is similar to the canine distemper, hepatitis, and parvo vaccines in that they are also modified live virus vaccines (MLV's) and have scientifically proven long durations of immunity. After the childhood series of live polio vaccines, I've never known anyone who has had a booster or even had a physician suggest that they take a titer to check their antibody count.
The 2003 American Animal Hospital Canine Vaccine Guidelines (
http://www.leerburg.com/special_report.htm ) state that:
"There is no indication that the immune system of canine patients functions in any way different from the human immune system. In humans, the epidemiological vigilance associated with vaccination is extremely well-developed and far exceeds similar efforts in animals whether companion or agricultural. This vigilance in humans indicates that immunity induced by vaccination in humans is extremely long lasting and, in most cases, life-long."
The vaccines in the quote above are CDV (distemper), CPV-2 (parvovirus), CPI (canine parainfluenza), and CAV-2 (hepatitis), and Dr. Ronald Schultz is the Chair of the Department of Pathobiological Sciences at the University of Wisconsin School of Veterinary Medicine. His challenge and serological studies on canine vaccines form a large part of the scientific data base upon which the 2003 and 2006 American Animal Hospital Association's Canine Vaccine Guidelines are based, as well as the 2007 World Small Animal Veterinary Association's Vaccine Guidelines. Dr. Schultz is currently conducting the concurrent 5 & 7 year rabies challenge studies for The Rabies Challenge Fund.
http://www.vetmed.wisc.edu/people/ronald%20d%20schultz
Kris