Current recommendations for vaccination are that cats and dogs receive an annual vaccination.  Many veterinarians and owners however believe that most cats and dogs do not need such a high level of vaccination, and that the animals really only require 2 or 3 shots throughout their whole lives.  This high level of vaccination is currently based on what the vaccine manufacturers decide to ensure optimal immunity for the whole broad range of pets.  Vets are required ethically and legally to follow the manufactures instructions with regard to the frequency of vaccination.  Some people believe that vaccinations at such a high rate lead to other secondary diseases such as degenerative joint diseases, lupus and suppress the immune system. 

The trouble occurs that the vets really have no way of truly knowing the immune “status” of a particular animal.  In fact there is no way of truly knowing this.  Some animals acquire lifelong immunity from their first shot, other gain hardly any. The truth is that each cat and dog’s immune system responds differently. No one can tell which animal is protected and which animal is not, this is the reason for annual vaccinations.   So if an owner asks the vet if his or her animal really needs the vaccination, the vet has no way of knowing the individual animal’s immune status, which means the vet and the owner would be guessing.  The vet cannot say in all honesty that the animal will be alright for another year.  If the vet did so and the animal contracted the disease they would be open to being sued. 

Pros & cons of vaccination
Like all drugs, there are potential side-effects.  Most side-effects from vaccinations are short lived, usually lasting less than 48 hours.  Common side-effects include localised swelling, pain at the site of injection and lethargy.   More serious side-effects include fibrosarcoma and autoimmune haemolytic anaemia.  These occur at a rate of between 1 in 10,000 to 1, 100,000.  People believe that due to the severity of side-effects and the scarcity of the disease, that vaccinations are no longer necessary.  However it is important to understand that many diseases become rare only due to intensive vaccination efforts and those owners who leave their pets unvaccinated are actually relying on the rest of the population vaccinating theirs.

Evidently the major benefit of vaccination is the prevention or decreased severity of a disease in a single organism.  On a large scale there are even more benefits.  First is the prevention of diseases that can cross over to humans such as rabies and salmonella.  Thus animal vaccination provides protection to humans as well.  Second is disease prevention in large groups of animals, specifically food herds such as cows, sheep and pigs.  Vaccination prevents the outbreak and spread of disease which may wipe out whole herds.  Not only is there a loss of food, but there are also significant economic losses.

Thought needs to be given as to whether the potential risks outweigh the benefits of vaccination.  Many of the diseases that can be vaccinated against are dreadful and if contracted many lead to death.  The pet needs to be assessed as an individual, some questions to be considered might include: how at risk of disease is the animal?  How likely is the vaccine to cause side-effects?  What is the animals’ current state of health?

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