Ask the Doctor - Vaccines And The Immune System

In order to give our readers the best possible answers to their questions, Dr. Stockner suggested that we contact Dr. W. Jean Dodds for an answer to the following question on vaccines. We are extremely grateful for the very comprehensive answer Dr. Dodds has given us (particularly since she lives in Santa Monica and is still in the process of recovering from the recent earthquake we received in So. California).

Recently I have discussed and read several articles on the use of killed vaccines and their advantages. I have always used compound vaccines. However, this last time I split up my vaccines over a month. The last one my dogs received was killed Coronavirus by Fort Dodge. I have 6 year old, 3 year old and 2 year old female Mastiffs, a 2 year old male Mastiff and 2 small mix-breeds of 14#. The morning after the guys received their shots, the 6 year old was swollen at the site of the injection. Their was a slight swelling on the other two girls. However, the other three dogs showed no indication of a problem. Sheba (my 6 year old) and Joli (the 3 year old) are both Thyroid and vWD tested A O.K. Sheba's swelling increased over a three day period and her glands on the back of her legs also swelled. In three days however, Joli's started to decline and Baby's (1 year 10 months) had disappeared. I now understand that corona is not necessary for adult dogs.

What do you think happened with the swelling and what are your views on a healthy vaccination schedule for puppy to adult (Mastiffs) and a once-a-month heartworm for pregnant bitches.

Sincerely,

Mary Hebert
Cypress Landing Mastiffs
Guydan, Louisiana 

The questions you have raised about the advantages and disadvantages of killed versus modified live virus vaccines, and a recommended schedule for vaccinating healthy animals from puppyhood to adults are important and timely. A good review on this general subject is provided by Dr. Christine Wilford in the January 1994 American Kennel Club Gazette. Dr. Wilford addressed many issues in her article and had the courage to emphasize that all too often we give too many vaccines too frequently, and do so to animals that are not in the peak of health at the time. She also recognized that some animals may have underlying immune dysfunction or have compromised immune systems such that adverse reactions to vac- cinations can occur. The general recommendations she's made for vaccinating healthy animals are sound and should produce few, if any, significant adverse reactions. Another source of information is from my friend and colleague, Dr. Sandra Priest, who wrote in the May 1992 issue of Dog World. Chart 2 of her article lists the vaccine protocol I generally recommend.

age in weeks       vaccine

5-1/2 to 6-1/2     distemper + measles +/- parainfluenza (without hepatitis)
6-8 & 10           distemper +/- parainfluenza (without hepatitis)
                   for pups not receiving measles earlier
7-8 & 10-11        killed canine origin parvovirus given 3-4 weeks apart
                   (same schedule and product each time)
12                 distemper + hepatitis + parainfluenza + leptospirosis (without parvovirus)
14 & 18-20         distemper + hepatitis + parainfluenza + leptospirosis 
                   + killed canine parvovirus (same schedule and product origin each time*)
16-24              killed rabies vaccine

*Alternatively, killed parvovirus vaccines and the distemper + hepatitis +
parainfluenza + leptospirosis combination can be alternated every two weeks
during the 14 to 20 week period.

My own writings on this subject span a decade or more, the most recent being an article in the May 1993 issue of Veterinary Forum. In these articles I raised several key questions about the safety and efficacy of current vaccine practices.With respect to the specific vaccine for corona virus, I do not recommend vaccination for this disease. The reasons are the same as those outlined by Dr. Wilford in her current article, namely, why vaccinate for a disease when "most experts agree that naturally occurring corona virus infection is insignificant and self-limiting"? This statement can be adopted more broadly.

It can be argued that vaccines should not be given for any diseases that fail to cause significant clinical problems because even the safest vaccine can induce adverse effects in some animals. Furthermore, as protection against corona virus requires local immunity, the current corona virus vaccine which produces a systemic and not local effect, may not be very effective. The swelling you encountered at the sight of injection and involving lymph glands in the legs could reflect an immunological challenge induced by the killed vaccine virus and/or any adjuvant that has been added to help boost the immunological response. My recommen- dation, therefore, would be to discontinue use of the corona virus product.

You also asked about the advisability of giving monthly heartworm preventives for pregnant bitches. In general it's advisable to avoid unnecessary challenges to the health or immune system of animals that are undergoing hormonal changes such as estrus and pregnancy. It is specifically not advisable to vaccinate animals during these periods nor during the time of lactation, because of the exposure of young puppies to shed vaccine viral antigens from the feces of the vaccinated dam or other adults in the household. With respect to heartworm prevention, the manufacturer's directions should generally be followed if these products are used. There appears to be no contraindication for use of either of the monthly heartworm products during pregnancy. However, that does not mean it would be advisable to do so for all breeds of dogs under all circumstances. Certainly in a breed like the Mastiff with a relatively small gene pool and large size, the behavior of these animals to a variety of chemical and other immunological challenges may vary from that expected for the more co- mmon breeds of dogs or mixed breed dogs. I have seen adverse reactions to monthly heartworm preventives in animals that appear genetically and physiologically susceptible to these effects. Therefore, I recommend that these animals and their direct relatives or dog families/breeds with an apparent increased prevalence of immunological disorders, avoid use of the monthly heartworm preventives. Instead, I advise use of the plain daily heartworm products. The adverse reactions usually occur within the first 10-14 days after the monthly product has been administered, and typically begin after an animal has had 2-5 doses. Occasionally animals that have been taking monthly preventives for a relatively long time will develop subsequent product intolerance. It usually means that some underlying disease process has emerged to explain the problem. This is an important consideration, because if breeders are concerned and wish to return to using plain daily products, we should do so lest these products disappear from the marketplace (if the manufacturers deem that sales are insufficient to warrant their continued production).

Lastly, it should be emphasized that unless heartworm disease is prevalent where the animals live, routine use of preventive is not recommended. This is especially important for dogs suffering from chronic allergic diseases of the skin and hair coat or those with bone marrow, thyroid or liver disease. [Specific literature references are available upon request]. W. Jean Dodds, DVM, Hemopet, 938 Stanford Street, Santa Monica, CA 90403 (310) 828- 4804.