Young puppies are highly susceptible to certain infectious diseases and should be vaccinated against them as soon as they are old enough to build immunity. These diseases are distemper, infectious hepatitis, parvovirus, parainfluenza, and rabies.Leptospirosis, giardia, coronavirus, bordetella, bronchiseptica, and Lyme diseasevaccinations are optional, depending on the occurrence of these diseases in your area and your dog’s individual risk factors.
The American Animal Hospital Association (AAHA) has drawn up guidelines categorizing vaccines as core or noncore, and these categories will be indicated for all the vaccines described in this section. While these guidelines suggest that puppies as young as 6 weeks may be vaccinated, most veterinarians and breeders wait until 7 or 8 weeks of age. Also, vaccine recommendations state that many vaccines do not need boosters beyond 12 weeks of age, but veterinarians, particularly in endemic disease areas, may do a final puppy vaccine at about 16 weeks.
Canine Distemper (Core)
A recombinant distemper vaccine is now available and, ideally, dogs will receive either an MLV or a recombinant version of distemper vaccine.
The first distemper shot should be given shortly after weaning and before a puppy is placed in his new home and is exposed to other dogs. Some veterinarians recommend vaccinating puppies at 5 to 6 weeks of age, using a combination canine distemper-measles-parainfluenza vaccine. The rationale for combining distemper and measles vaccines is that a high percentage of 6-week-old puppies do not get a satisfactory response from the distemper vaccine alone because of maternal antibodies that neutralize the distemper antigen. The measles virus, which is quite similar to the distemper virus, can overcome maternal antibody interference and induce partial distemper protection. Alternatively, if maternal antibodies have actually disappeared in the 6-week-old puppy, the distemper portion of the vaccine will induce complete protection.
The distemper-measles vaccine should be used only once, for the first vaccination, and only in puppies. The newer recombinant distemper vaccine seems to overcome maternal antibodies and is now believed to be a better option than the distemper-measles combination.
Postvaccination encephalitis has occasionally occurred when an MLV distemper vaccine has been used in combination with a parvovirus vaccine in pups younger than 6 to 8 weeks of age. Therefore, parvovirus vaccine should not be given along with the first distemper vaccination in very young puppies. The recombinant distemper vaccine is unlikely to cause encephalitis, and is therefore recommended for young puppies.
Puppies younger than 8 to 9 weeks of age should be revaccinated every four weeks until they are 16 weeks of age. Current recommendations are to revaccinate at 1 year of age or in a year from the last vaccination, and then every three years. This time period may be extended with future research data on duration of immunity.
Infectious Hepatitis (Core)
The infectious hepatitis vaccine is a MLV vaccine containing CAV-2. This vaccine protects against canine hepatitis and two of the adenoviruses involved in the kennel cough complex (CAV-1 and CAV-2).
Hepatitis vaccine is incorporated into the DHPP shot, which is given at 8 to 12 weeks of age and again at 16 weeks of age with a possible booster in between for puppies who were initially vaccinated at 8 weeks of age or younger. It is suggested that a DHPP booster be given at 1 year of age or one year from the last vaccine. Revaccination is currently recommended every three years, although initial immunity may persist for life.
Canine Parvovirus (Core)
Commercially available vaccines effectively cross-protect against all the current strains of parvo, including variant strains. The MLV vaccine is much more effective than a killed vaccine in that it produces a faster and stronger immune response.
Because the age at which individual pups can respond to parvovirus vaccination varies, AAHA 2006 guidelines are to give the vaccine at 6 to 8 weeks of age, then every three to four weeks until the dog is 12 to 14 weeks of age, but many veterinarians prefer to wait until a puppy is 7 or 8 weeks of age to start parvo vaccinations and conclude them at 16 weeks.
High titer-low passage vaccines (see page 91) are more effective than older vaccines, even in the presence of maternal antibodies, and have narrowed the window of susceptibility that occurs between declining levels of maternal antibodies and acquired immunity produced by the vaccine. This has resulted in fewer vaccine failures.
Even after a pup has received his first series of vaccinations, he should not be exposed to dogs who may be a source of infection until after he receives his final vaccination at 16 weeks of age. Boosters are recommended every three years to maintain immunity, following an initial booster at one year. This interval may be increased with further research on vaccine efficacy.
In unvaccinated dogs older than 16 weeks, give two doses of vaccine two weeks apart. Brood bitches should be vaccinated two to four weeks before breeding to ensure high levels of antibodies in their colostrum. Some veterinarians believe this booster is unnecessary.
The first rabies vaccination should be given at 3 to 6 months of age, with the first booster shot given one year later (at 15 months of age). Thereafter, give boosters annually or every three years, according to state and local statutes. Rabies vaccination schedules are regulated by law.