Extended duration of immunity

In recent years, some vaccines for dogs have been able to extend the duration of immunity to three years for canine parvovirus, infectious canine hepatitis, canine distemper and rabies components. For cats the duration of immunity for panleucopaenia of some vaccines has been extended to three years. So, if an animal has been vaccinated for one of these, re-vaccination against these diseases will be due 36 months later, not 12 months later.

However, re-vaccination against kennel cough or parainfluenza and leptosirosis for dogs, and 'flu for cats in the form of a booster will be due 12 months later.

For the sake of clarity, all vaccination certificates supplied by MSD Animal Health to vets now include a ‘protected until’ date for each vaccine. This is the date you should check when determining whether the pet is fully protected.

How long before a stay should boosters be given?

This depends on whether the previous vaccination is still in date or not.

Previous vaccination is still in date

If the previous vaccination is still in date at the time the booster is given, the animal will remain protected. In this particular circumstance, there is no reason to refuse the animal, even if the booster was given an hour before boarding.

Some modified live vaccines are shed by the animal after it has been vaccinated. Some kennels have therefore refused animals that were protected by earlier vaccinations to board within 14 days after the most recent vaccination to avoid shedding of vaccine organisms to other animals in the kennel/cattery. There is however no need to do this. The authorities in the UK will only license a product if the manufacturer has shown that there is no shedding of vaccine organisms after vaccination, or in case shedding occurs, this does not result in problems for in-contact animals.

Previous vaccination is not in date

In this particular situation, one or two vaccinations are required to induce sufficient immunity to protect the animal against infection. Depending on the vaccine, it will take 3-14 days before this immunity has been established. As the animal may have been incubating disease at the time of the booster, it is wise to allow at least 14 days between booster and boarding.


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