Wednesday, January 11, 2012

My Vaccine Philosophy

I originally wrote this for my clients who asked about my vaccine protocols and it evolved into something a bit longer.  I am posting it hear for anyone who is interested.  Though I removed most of the cat information (since this is primarily a dog blog), you can find the cat information here:


http://www.rightathomevetcare.com/vaccines.html


Introduction:
Vaccines have saved countless human and animal lives and prevented many serious and fatal diseases.  But vaccines are not 100% benign either.  Although rare, vaccines can sometimes cause sarcomas in cats and immune mediated hemolytic anemia (IMHA) in dogs along with the more common anaphylactic reactions.  While largely unproven in veterinary medicine, some are quick to point their fingers at vaccines for a myriad of other diseases and conditions, including allergies, seizures, and behavior problems.  Some breeders and owners are now very proud of the fact their dogs are not ever vaccinated.  So do we throw the baby out with the bath water?

As a holistic veterinarian that also looks at things with a scientific perspective, my conclusion is to look at the individual.  I use vaccines judiciously.  I also believe that not every pet is going to require the same vaccines and a cookie cutter approach for all animals is not the right way to go.  As a veterinarian and a guardian of public health, I do not make the rules, but I must follow them.  So what vaccines are required by law?  Typically only rabies, so we will discuss rabies first.  In the state of Missouri, dogs and cats must be vaccinated every 3 years and ferrets must be vaccinated every year.  In addition, though vaccines carry certain risks, no life of an animal is worth that of a human if a child bitten by a rabid animal (domestic or wild) that could have been prevented.  The following is a video of a child in southeast Asia who contracted rabies.  It is not an easy video to watch.

Child with Rabies

However, this is reality for the 55,000 people worldwide who contract rabies and die from this nearly always fatal disease.  In North America, we usually think of wild animals such as skunks, bats, foxes, and raccoons having rabies, but in most other countries, dogs are the most likely animal to spread rabies to humans.1  The reason so few people in the United States contract rabies is the successful vaccination of our pets.

Before getting into what I recommend in my practice, let's discuss some terminology.

Antigen: a foreign substance that the immune system recognizes as a potential threat to the body.  This can include anything from bacteria, viruses, and fungi to pollens and things in the environment that cause allergies.

Antibody:  a protein produced by the immune system used to identify foreign antigen.  Antibodies help the body's immune system identify antigens faster and help prevent disease before it takes hold in the body.
Vaccine:  a biological agent composed up of antigen introduced in the body to stimulate the immune system into producing antibody.  Vaccines are usually for viruses and bacteria.  Note that vaccines or natural immunity from previous exposure to the infectious agent do NOT prevent infection (so called "sterilizing immunity"), but prevent disease in the body by allowing the immune system to recognize infectious agents faster and make it less likely that the patient becomes sick.

Modified/Attenuated Live Vaccines (MLV):  These vaccines have been cultured in a way to prevent them from becoming virulent while still causing a more robust immune system response and better antibody production.  Canine distemper and feline rhinotracheitis virus (herpes virus) are examples of commone modified live vaccines.

Killed Vaccines:  These vaccines have the infectious agent in them killed so they cannot resort back to virulence.  This is important in viruses such as rabies.  Killed vaccines do not stimulate as robust of an immune system response as a modified live vaccine and contain adjuvant.

Recombinant Vaccines:  These vaccines use a newer technology to mix or "recombine" the DNA of the desired organism into a less harmful organism.  Examples of this are the newer feline leukemia and feline rabies vaccines.  Recombinant vaccines do not contain adjuvant.

Adjuvant:  an additional component of vaccines that is used to "irritate" the immune system into a stronger response.  These are typically used in killed vaccines such as rabies vaccine because killed vaccine is not recognized as strongly by the immune system as modified/attenuated live vaccine.  The use of adjuvant is controversial due to the ability to cause vaccine associated sarcomas in some cats.

Thimerosol:  An organomercury preservative added to certain vaccines.  Its use is controversial in both human and veterinary vaccines.

Dosing Tank:  The vials the vaccines come in.  When vaccine is manufactured, they come in either multidose tanks or single dose tanks.

Antibody Titer:  An estimate of the amount of antibody to a particular disease causing agent such as a virus or bacteria that the body has made.  Usually done by a blood test sent to a laboratory.  Can be used to judge if a patient has an appropriate level of antibodies to fight off a disease.  However, levels of antibody that are protective are controversial and an animal with a low level still might not come down with the disease (antibodies are not the only mechanism of defense in the immune system).  Conversely, some animals with a high level of antibody may still come down with the diease.  Titers are generally used as guidelines on whether or not to revaccinate.

Maternal Antibody:  Depending on the species, some animals pass on a certain amount of antibody to their offspring via the placenta and through nursing (dogs and cats) and have maternal antibodies present if the mother was previously vaccinated.  Other species, such as horses, have very little maternal antibody at birth and foals rely solely on taking in their mother's colostrum by nursing around the time of birth.  In dogs and cats, the time the maternal antibody decreases is highly variable.  They may wane at 5 weeks or at 20 weeks.  We vaccinate puppies and kittens in a series to make sure they can form their own antibody when the maternal antibodies have declined to protect from potentially fatal disease like parvo and distemper virus.

Herd Immunity:  This is the idea that a certain percentage of a population (be it dog, cat, cattle, humans, etc) must be immune to an infectious contagious disease either through natural immunity through exposure to the infectious agent or vaccination in order to "spare" the individuals who have not been exposed.  Outbreaks tend to happen when fewer animals are vaccinated.  The exact percentage that needs to be immunized to offer some protective herd immunity differs by disease, but is typically at least 75% of the population.

Core & Non-Core Vaccines:  Recommendations from the American Animal Hospital Association (AAHA)2 and the American Association of Feline Practitioners (AAFP)3 on which vaccines (beyond rabies by law) that our pets should or should not get based on their lifestyle.  Core vaccines are designated such because of the highly contagious and possibly fatal nature of the diseases, while non-core vaccines will depend on geographic area and what the animal is exposed to.  Other non-core vaccines are designated this way because their vaccines

My Philosophy:

In my practice, I want to use the best technology for my patients and make sure they are protected while minimizing the risk of vaccine reactions as much as possible.  While I feel they are better products, they are typically more expensive than the older versions both for me and for the client, but I feel it is worthwhile to keep our pets protected while minimizing risks.

I prefer to use single dose tanks.  The reason for this is that I want to be sure that even if the vaccine is properly mixed that the patient received the correct amount of antigen in the vaccine:  not too much and not too little.  These are typically more expensive than multidose tanks.

I also prefer to use 3 year thimerosol free killed rabies vaccine as this is currently the best technology on the market for dogs.  In cats, the best technology for rabies and feline leukemia uses recombinant canary pox vaccines.  At this time, this particular vaccine is only approved for once a year but they do not contain adjuvant, which is a big plus for cats.

I recommend spreading vaccines out with a minimum of two weeks in between this is for several reasons.  First, if a dog or cat has a reaction to a vaccine, I want to know which type.  I also want to make sure the body is not overwhelmed with antigens all at once and has sufficient time to develop antibodies.  I also give vaccines in specific locations.  The older way was to give all vaccines between the shoulders at the pet's scruff.  Now the recommended way is to give them in specific locations, such as rabies=right rear and feline leukemia=left rear, so you know which vaccine did what if there is a problem.

For other vaccines, I tend to follow the American Animal Hospital Association (AAHA) and American Association of Feline Practitioners (AAFP) recommendations for "core" and "non-core" vaccines.  While every dog and cat is different, I have essentially two approaches:  a more "standard" approach and a more holistic approach.  They are as follows for dogs and cats.

Core Dog Vaccine Protocol (Most Pet Dogs):

8 weeks:

DA2PP (distemper/adenovirus type 2/parvovirus/parainfluenza) MLV

12 weeks:

DA2PP MLV

14 weeks:

Rabies (thimerosol free) as by law (must be done by 3 months per the city of Columbia)

16 weeks:

DA2PP MLV

20 weeks:

Distemper/parvo titer if desired
Twelve Months Later:

Rabies (thimerosol free, start of 3 year rabies)
Distemper/parvo titer (if low, re-vaccinate 2-4 weeks after rabies)

Four Years (and every three years after):

Rabies (thimerosol free, 3 year)
Distemper/parvo titer if desired (if low, re-vaccinate 2-4 weeks after rabies)

Non-Core Dog Vaccine Protocol:

As explained earlier, non-core vaccines will depend on the dog's lifestyle and exposure.  A field trial or coonhunting dog might benefit from leptospirosis while a conformation dog that is at dog shows every weekend may benefit from bordetella, particularly if the dog is required to have this vaccination for shows, classes, grooming, and so on.  Some vaccines, such as corona or giardia, have low efficacy or the disease they are trying to protect from is fairly self limiting.  For these reasons, they are not generally recommended at this time.

1 comment:

  1. It is true that dogs are the part of family member for all pet owners so dogs health is as important as our health. We have to take care of our dogs health and do regular checkup of dogs health by veterinarian.

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