Dear Editor,
The following are my responses to my comments discussed in Dr. Lahey’s letter.
“Dr. Schultz appeared to be encouraging breeders to administer their own vaccines and explained that veterinarians are misguided by current vaccine protocols and are just making money off people.”
As should be evident to Dr. Lahey and all veterinarians, many breeders buy and administer vaccines and have done so for many years. My goal is to educate them about the different types of vaccines, how they work, and when and why they should or should not be given. That is also the reason I placed a copy of the World Small Animal Veterinary Association (WSAVA) Vaccination Guidelines for the Owners and Breeders of Dogs and Cats authored by Day MJ, Horzinek MC, and myself, in the Proceedings Book for the K-9 College Cruise (http://www.wsava.org/PDF/Misc/WSAVA_OwnerGuidelines_September2010.pdf ). I also placed in the Proceedings Book “What Breeders and Dog Owners Need to Know About Canine Vaccines and Vaccination Programs.” If veterinarians “are misguided by current vaccine protocols [guidelines]”, then I am more at fault than probably anyone! I have been personally involved in the development of canine and feline vaccine protocols for more years than most. I, and my colleagues, have been publishing vaccination protocols for dogs and cats since the 1970’s in journals, books (for example, Kirks’ Current Veterinary Therapy, the Veterinary Clinics of North America, AAFP Feline Guidelines, AAHA Canine Guidelines, and WSAVA Canine and Feline Guidelines) and in giving seminars at meetings worldwide. I have also served as a driving force for the development of National and International Canine and Feline Vaccine Guidelines.
There is excellent evidence for lifelong immunity to CDV, CPV-2, and CAV-1 in the dog, and FPV in the cat. This is similar to the lifelong immunity to measles, mumps, and rubella after childhood vaccination. Of course, this requires that the dog, cat, or human was appropriately vaccinated and immunized! When vaccines are shown to provide at least 3 or more years of immunity in a dog or cat, which all of the current major manufacturers’ CDV/CPV-2/CAV-2 for the dog and FPV for the cat have shown, that is equivalent to lifelong in a species that lives an average of 10 to 15 years, just as 20 to 30 years for a human vaccine is evidence that it will provide lifelong immunity. However, there have been many studies based both on challenge and antibody titer showing that antibody and protective immunity persist for over 7 years for current canine and feline core vaccines in the absence of revaccination and absence of the viruses. References for those studies were sent to Dr. Lahey. Similarly, antibody can be shown to persist in humans to MMR for a lifetime in the absence of overt revaccination. This long-lived immunity in dogs, cats, and humans occurs as a result of long-lived plasma cells. Obviously, this long-lived immunity is not seen after all vaccinations: for example, protection from Leptospira, Borrelia (Lyme), or Bordetella is generally considered to be a year, plus or minus a few months. Whenever it can be shown that recovery from natural infection, which leads to natural immunization, provides lifelong immunity, we should be able to make a vaccine that can also provide lifelong immunity! Likewise, if natural immunization only provides 1 or 2 years of immunity, you won’t be able to make a vaccine that provides lifelong immunity.
I didn’t encourage “breeders to take their own blood samples and send them to [my] personal laboratory for [my] interpretation of vaccine titers”! What I encouraged was if they wanted a nomograph performed to know when the best ages were to vaccinate their puppies with CDV or CPV-2 vaccines, they should send the samples, because our laboratory is the only one that does the nomograph. Frequently, I receive blood samples from veterinarians, shelters, owners, and others. I don’t know what is meant by “his personal laboratory.” My laboratory is at the University of Wisconsin-Madison, and it is supported by research grant funds, gifts, and income generated from providing testing services.
I was asked about how long the vaccines remain effective after they are reconstituted and how long they may remain viable with regard to expiration date. My response was we recommend that after reconstituting the live vaccines like CDV/CPV-2/CAV-2 combination that it be used within 1 hour if possible but don’t allow it to remain at room temperature for more than 3 hours. If it is reconstituted and kept at refrigeration temperature, it should be used that same day. I did say that some of the component vaccines in combination products were more labile than others. For example, the CDV would lose viability sooner than CAV-2 and CPV-2 remains viable for much longer than the others. I also said that the CDV would more likely lose viability close to the expiration date. However, I had a CPV-2 vaccine that was 10 years from expiration and the vaccine virus was able to infect and immunize the dog! Comparing how one component is highly labile and another is very stable is not the same thing as recommending that expired vaccines be used. The bottom line was don’t use combination live viral vaccines that are expired by weeks or months, because it is likely they will not provide protective immunity to all the components! The expiration date is based on the most labile component.