If you knew pet vaccines contained a trace amount of mercury or had a history of occasionally causing cancer, would you want your beloved dog or cat to receive it? Would you be willing to pay a few more dollars for a vaccine known to be safer, to cause fewer side effects, or to be more effective at protecting your pet?
There has been a shift in how we think of health and wellness, starting with careful consideration of the chemicals, preservatives, safety and technologies used in our food, our homes, and our healthcare systems. The wellness we desire for ourselves is what we want for our pets too.
Preventive care is a proactive approach that seeks to manage or prevent conditions before they become minor or major illnesses. Quality matters when it comes to the pet vaccinations your dog or cat receives because there are significant differences among vaccines which impact overall health and wellness.
Understanding Pet Vaccines: Brief definition of terms
In order to understand why the quality of pet vaccines matters, it’s important to understand a few terms.
- Antigen: A substance (foreign to the body) that when introduced into the body stimulates the production of an antibody. Antigens are typically proteins.
- Antibody: A protective protein complex that the immune system generates in response to an antigen.
- Vaccine: An innoculation of dead, weakened, or modified microorganisms (viruses, bacteria,) to produce immunity to a disease by stimulating the production of antibodies.
- Canine Distemper Virus: A highly contagious virus similar to the virus causing measles in people.
- Canarypox Virus: A virus that replicates only a little and does not cause clinical disease in cats and dogs, which can be used to deliver many vaccines (e.g. canine distemper, feline leukemia virus or rabies) safely and effectively.
- Rabies: A fatal viral disease in mammals affecting the central nervous system.
Safety and Efficacy of Pet Vaccines
For people or pets, the goal with any vaccine is to have a low incidence of unwanted side effects and high efficacy. How the vaccine is designed and manufactured can determine how well the vaccine works and what side effects are anticipated. Traditionally, vaccines contain either a “killed” microorganism or a “modified live” microorganism.
- Killed microorganism – Vaccines using a killed microorganism contain a relatively larger amount of foreign protein to ensure an adequate immune response against the disease. In order to get the best response from the immune system, chemicals, called adjuvants, are often added to cause inflammation at the injection site which helps to boost the immune response to the inactive proteins in the vaccine.
Generally with this type of vaccine, there are more unwanted side effects and less effective protection. The added adjuvants occasionally cause other problems, ranging from lumps of granulation tissue at the injection site to fibrosarcoma (a malignant cancer) in cats.
- Modified live microorganism – Vaccines with a modified live microorganism contain bacteria or virus that has been altered—using chemicals, heat or other means—to make the microorganism less dangerous to the host, yet adequate to elicit a protective immune response. There are different risks and generally fewer side effects with modified live vaccines than with killed vaccines.
Modifying microorganisms can be tricky if the change to the microorganism is not right; the result can range from an ineffective to a deadly vaccine.
- Vectored vaccines – From more recent developments in DNA science, vaccines can also be created using what is called vectored technology. This method reduces the offending virus, canine distemper or rabies for example, to one or a few specific genes. The microorganism DNA that codes for those genes are then combined with the carrier (canarypox virus) DNA. The canarypox virus is not dangerous to dogs and cats. When the modified canarypox virus is injected into a dog or cat, the virus replicates a little, transcribing its proteins, including the few specific proteins from the canine distemper virus for example. The dog raises antibodies against those particular distemper virus proteins, and these antibodies confer protection to the dog against canine distemper.
Essentially, vectored vaccines have captured the best qualities of the two older vaccine manufacturing methods, with many fewer unwanted side effects than either of the older methods.
Vaccines often contain preservatives to prevent bacterial contamination that could be life threatening. Thimerosal is a preservative which contains mercury. Many animal (and human) vaccines containing thimerosal are still used today. Doylestown Veterinary Hospital has not used any vaccines containing thimerosal since Drs. Randy and Laura Weis bought the practice in 2000.
The efficacy of vaccines varies greatly from one manufacturer to another, and typically depends on the technical details of how the vaccine is produced. For example, the efficacy of many of the Lyme vaccines on the market today is roughly 60-65%, while two other Lyme vaccines are almost 100% effective. The same can be said of feline leukemia vaccines. Coincidentally, for both of the above mentioned vaccines, the ones with the best efficacy also have the lowest rate of unwanted side effects. Which vaccines would you want for your four-pawed friends?
The cost of quality
Quality vaccines—vaccines with high efficacy and low side-effect rates, without thimerosal or adjuvants—cost more than vaccines made by older technologies. Generally the cost difference is approximately $10-15 per vaccine. This cost is trivial compared to the monetary cost as well as the ordeal to the pet and owner of treating a pet experiencing a mild or severe side effect, or worse yet, having the pet suffer temporarily or permanently from a disease easily prevented with a safe, effective vaccine.
Preventive medicine at Doylestown Veterinary Hospital
Preventive medicine for a lifetime of health and wellness is the focus at Doylestown Veterinary Hospital so the quality of vaccines used is very important. Dr. Randy Weis, co-owner of the veterinary practice, puts a lot of work into making sure the vaccines have the highest levels of safety and efficacy. Doylestown Veterinary Hospital does not administer any vaccines to dogs and cats containing thimerosal, and all feline vaccines are adjuvant-free.
When asked about Lyme disease, Dr. Randy Weis said:
“We live in an area known to have some of the highest rates of Lyme disease in the country, carried by our resident tick-species. We discuss Lyme disease with our clients, and strongly encourage vaccinating almost any dog living in Bucks County against Lyme disease. We use a vaccine with a clearly demonstrated virtually 100% efficacy rate. Seventy to eighty percent of adult dogs entering our practice are chronically infected with Lyme disease. By stark contrast, we see one or two new cases a year in vaccinated dogs within the practice. Effective tick-borne disease prevention also requires effective tick-killing products on the pet, and there are other potentially serious tick-borne diseases besides Lyme disease.”
When providing your pet with the best nutrition and the best wellness care for a long healthy and happy life, the quality of vaccinations your pet receives over a lifetime should be an important consideration. Preventive care is meant to keep your pet healthy while helping avoid the cost and stress associated with treating life-threatening diseases. The first line of defense is a quality vaccine that provides the best protection with the fewest, mildest side effects. Talk to your veterinarian about the variety of vaccines available and which one is the best option for your pet.