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An Urban Experience
would be given at 26 weeks of age (and replaces the vaccine that has previously been given either at 12 months of age or 12 months after the anniversary of the 16 week vaccine). This fourth vaccine might conveniently be given at the time of neutering of the puppy. By this schedule, all puppies (except genetically-determined
low or non-responders) will be able to mount protective immunity by 26 weeks of age. Where rabies is endemic, pups should receive 1 dose of vaccine at 12 weeks of age or older, but the VGG suggests that in a high-risk situation (i.e. in an endemic area with known local cases), a second dose of vaccine may be given 2 - 4 weeks later.
The ‘window of susceptibility’ to infectious disease for puppies overlaps with the ideal period to undertake socialization. The WSAVA guidelines endorse strategies to socialize puppies (including ‘puppy parties’), but recommend simple measures to minimize the low risk of transmission of infectious disease at such events.
Core Vaccination of Adult Dogs
For adult dogs, MLV core vaccines should be given no more frequently than every 3 years. For CDV, CAV, CPV there is excellent correlation between the presence of serum antibody (as detected by virus neutralization
test or haemagglutination inhibition test or in-house serological test kits) and protection from challenge with infectious virus. There are extensive data showing that protective antibody persists in adult dogs, even when they have only been vaccinated as puppies up to 14 years previously [6, 7]. More importantly there are data that underpin the legal registration of canine core MLV vaccines for either 3 or 4 years, based on challenge studies that show that vaccinated dogs resist infection for that minimum period after vaccination (the minimum duration of immunity, DOI). Other experimental data show that dogs vaccinated as puppies only are protected from live virus challenge with CDV and CPV at 9 years of age [8]. On this basis, most of the internationally produced canine MLV core vaccines used in the USA, Europe and some other countries now have a licensed minimum DOI of either 3 or 4 years. However, in other countries the identical international vaccines still carry a 1-year licensed DOI, but may still be used less frequently with informed client consent.
This is also true for the internationally produced
killed adjuvanted rabies vaccines that may legally be given every 3 years rather than annually. Where such products are available with a 3-year licensed DOI,
but governmental legislation insists on annual rabies vaccination, it is beholden on the veterinary profession to lobby for changes to the law in order to prevent unnecessary revaccination of adult dogs. For example, in the USA, state laws changed gradually, such that now every US state stipulates triennial revaccination of dogs against rabies.
The currently accepted core revaccination schedule for adult dogs is therefore revaccination every third year with CDV, CAV, CPV and rabies. Where rabies revaccination is still required annually, the schedule might be CDV, CAV and CPV triennially and rabies annually. Triennial revaccination is simply better evidence-based medical practice, but also reduces the number of unnecessary vaccines given to adult dogs and therefore reduces the chances of adverse reactions.
Vaccination according to WSAVA guidelines necessitates being able to source vaccine ranges where products
are formulated with minimal antigenic content (e.g. combination MLV DAP vaccines, with separate non-
core components). In many countries, only multiple combination products are available and so veterinarians in those regions should urge manufacturers to license the minimal component ranges available elsewhere in their countries.
Non-core Vaccination
Non-core vaccines should be selected for the individual dog based on assessment of that particular animal’s
risk of exposure to the disease and assessment of the benefits of vaccination to that pet versus the risk of adverse reaction. Decision making for non-core vaccines would be facilitated by having available good quality data and disease distribution maps related to small animal infectious diseases. Unfortunately, with the exception of rabies in the USA and Europe, such distribution maps are not widely available. Some national schemes have been developed by industry or academic groups which allow practitioners to input cases of particular infectious diseases into a database that presents the information as disease distribution maps.
Monitoring the distribution and evolution of infectious diseases is an important part of vaccinology. An excellent example is canine leptospirosis, which has recently attracted much research interest as the importance
of particular serovars in causing canine disease in different geographical locations is determined. This new knowledge has led to the introduction of trivalent or tetravalent canine Leptospira vaccines in the US and Europe; the antigenic composition of which is related to the prevalence of serovars in each location. Similarly, in some countries (e.g. the USA and Korea) vaccines are available to protect against different strains of canine influenza virus (CIV). This infection remains an issue for dogs that are intensively kenneled and transported (e.g. racing greyhounds), but the CIV vaccine would not be recommended for general use among pet dogs.
Non-core vaccines may be included into the puppy vaccination schedule if dictated by risk assessment. For example, intranasal vaccines protecting against some elements of the canine infectious respiratory disease complex (i.e. CPi and Bordetella bronchiseptica) might be

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