THE FOLLOWING WAS WRITTEN BY DR'S CARMICHAEL & SCHULTZ FROM CORNELL UNIVERSITY
Dogs immune systems mature fully at 6 months. If a modified live virus vaccine (MLV) is given after 6 months of age, it produces immunity which is good for the life of the pet (ie: canine distemper, parvo etc.) If another MLV vaccine is given a year later, the antibodies from the first vaccine neutralize the antigens of the second vaccine and there is little or no effect. The titer is not boosted nor are more memory cells induced. Not only are annual boosters for parvo and distemper unnecessary, they subject the pet to potential risks of allergic reactions and immune-mediated hemolytic anemia.
There is NO scientific documentation to back up label claims for annual administration of MLV vaccines. Puppies receive antibodies through their mother's milk which can last 8 to 14 weeks.
Puppies should NOT be vaccinated at LESS than 8 weeks of age. Maternal immunity will neutralize the vaccine and little protection (0-38%) will be produced. Vaccination at 6 weeks will, however delay the timing of the first highly effective vaccine. Vaccinations given 2 weeks apart suppress rather than stimulate the immune system. A series of vaccinations should be given starting at 8 weeks and given 3 to 4 weeks apart up to 16 weeks of age. Another vaccination given sometime after 6 months of age (usually at 1 year) will provide lifetime immunity.
For distemper & parvo a series of vaccinations given at 2,3, & 4 months and again at 1 year with a MLV program memory cells that survive for life providing lifelong immunity. There are no new strains of parvovirus as one mfg. would like to suggest, parvovirus vaccination provides cross immunity for all types. "Hepatitis" (Adenovirus) is one of the agents known to be a cause of kennel cough, ONLY vaccines with CAV-2 should be used as CAV-1 vaccines carry the risk of "hepatitis blue-eye" reactions and kidney damage.
Bordetella Parainfluenza : Commonly called "kennel cough" vaccination is recommended ONLY for those dogs boarded, groomed, taken to dog shows, or for any reason housed where exposed to a lot of dogs. The intranasal vaccine provides more complete and more rapid onset of immunity with less chance of reaction. Immunity requires 72 hours and does not protect from every cause of kennle cough and immunity is of short duration (4 to 6 months).