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Vaccines are health products that trigger protective immune responses in pets and prepare them to fight future infections from disease-causing agents. Vaccines can lessen the severity of future diseases and certain vaccines can prevent infection altogether. Today, a variety of vaccines are available for use by veterinarians. Pets should be vaccinated to protect them from many highly contagious and deadly diseases. Experts agree that widespread use of vaccines within the last century has prevented death and disease in millions of dogs, cats, and other animals. Even though some formerly common diseases have now become uncommon, vaccination is still highly recommended because these serious disease agents continue to be present in the environment.

For most dog and cats, vaccination is effective and will prevent future disease. Occasionally, a vaccinated pet may not develop adequate immunity and, although rare, it is possible for these pets to become ill. It is important to remember that although breakdowns in protection do occur, most successfully vaccinated pets never show signs of disease, making vaccination an important part of your pet’s preventive health care. Although most pets respond well to vaccines, like any medical procedure vaccination carries some risk. The most common adverse responses are mild and short-term, including fever, sluggishness, and reduced appetite. Pets may also experience temporary pain or subtle swelling at the site of vaccination. Although most adverse responses will resolve within a day or two, excessive pain, swelling, or listlessness should be discussed with your veterinarian.

Rarely more serious adverse responses occur. Allergic reactions can occur within minutes or hours of vaccination. Signs of an allergic reaction include repeated vomiting or diarrhea, whole body itching, swelling of the face or legs, difficulty breathing or collapse. Contact your veterinarian immediately if any of these symptoms are seen. In very rare instances death could occur from an allergic reaction. There are other uncommon but serious adverse responses, including injection site tumors in cats, which can develop weeks or months after vaccination. Ask your veterinarian about any abnormalities you notice after your pet has been vaccinated. Remember that while vaccination is not without risk, failure to vaccinate leaves your pet vulnerable to fatal illnesses that are preventable.

Very young puppies and kittens are especially highly susceptible to infectious diseases. This is especially true as the natural immunity provided in their mothers’ milk gradually wears off. To keep gaps in protection as narrow as possible and to provide optimal protection against disease for the first few months of life, a series of vaccinations are scheduled, usually 3-4 weeks apart. For most puppies and kittens, the final vaccination in the series is administered at when they about 4 months of age.

Not all pets should be vaccinated with all vaccines just because these vaccines are available. Discuss with your veterinarian your pet’s lifestyle, access to other animals, and travel to other geographic locations, since these factors affect your pet’s risk of exposure to disease. “Core” vaccines are recommended for most pets in a particular area. “Non-Core” vaccines are reserved for pets with unique needs. Your veterinarian will consider your pet’s particulars, the diseases at hand, and the application of available vaccines to customize a vaccine recommendation for your pet.

For many years, a set of annual vaccinations was considered normal and necessary for dogs and cats. Veterinarians have since learned more about diseases and pets’ immune systems, and there is increasing evidence that immunity triggered by some triggered by some vaccines provides protection beyond one year. The immunity triggered by other vaccines may fail to protect for a full year. More than one successful vaccination schedule is possible. Talk with your veterinarian about what is best for your pet.

22 thoughts on “Vaccines

  1. Nash Rich says:

    I always figured all your pets needed all of the vaccines but I guess it makes sense that some would need different ones. I had never thought how a pets lifestyle could affect what it needs too. Thanks for all of the info!

  2. I never knew that they final vaccinations for puppies is administered when they are about 4 months old. We adopted our dog when he was about 1 year old, and he was already up to date on his vaccines. I will have to remember that if we get a puppy.

  3. I appreciate the tips for vaccinating puppies. Even if some pets react badly to these, I agree that it’s best to get our new puppy vaccinated. If most pets respond positively, I have no problem taking my puppy in.

  4. I liked that you had mentioned that it can be important to have your pet vaccinated to lessen the severity of future diseases and prevent possible infections. My wife and I have recently adopted a dog and she’s already become a large part of our lives and we’re worried about anything happening to her. We’ll have to start looking around for a company that handles vaccinations so that we can make sure our dog won’t be getting sick as often and will live a bit safer.

  5. Hazel Owens says:

    I didn’t realize that puppies and kittens needed scheduled vaccinations every 3-4 weeks so that they won’t be susceptible to disease. I just got a 1-month-old Australian shepherd last week. I’ll have to double check if she has gotten all her shots or if she needs more.

    • Tyler says:

      One month old? WAY too young to have left its mom. And you don’t even know about vaccines and that puppies need them? OMG.

  6. Gerty Gift says:

    I liked what you said about discussing your pet’s lifestyle before deciding the best vaccinations for them. We have been thinking about getting our dog vaccinated, but we didn’t really know how to approach it. We’ll make sure to discuss this with our vet so that she can get the best protection.

  7. Silas Knight says:

    We’re planning on getting a kitten soon, so this is great. It makes sense that when they’re young, they’re really susceptible to diseases and things. For that reason, I want to the kitten we get to have his or her shots.

  8. Vaccines are one of the most successful pharmaceutical scams to date. Animals are naturally immune to most diseases, the Parvo outbreak did not occur until AFTER they started vaccinating ‘against’ Parvo. Don’t do it people, don’t vaccinate! Vaccines also has caused autism in dogs….

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