Quote:
Originally Posted by Love4himies
The issue with vaccine lumps is that they can turn cancerous and apparently it can be malignant and aggressive. :sad: I have been so stressed this weekend and Jasper has been so spoiled.  Maybe Dr Lee can give me more info. |
Thanks Love4himies!
There has been a link established between cancer (VAS - vaccine associated sarcoma) and some vaccines in cats. (there is new evidence that to a lesser extent this is occurring in dogs as well). I think somewhere I did a long description of this here. In short, the adjuvants appear to be causing the cancer by means of prolonged and marked local inflammation.
Merial has developed vaccines (basic 4in1, feline leukemia and rabies) which are non-adjuvanted and to date, have not had known one case of cancer induced from them. During the research the feline leukemia vaccine, which has the highest rate of causing this tumor, was still causing tissue inflammation even after it was made as recombinant so they took a needless injector which was developed by the military. It injects the vaccine through a concentrated puff of air. By spreading the vaccine out, the tissue inflammation has been reduced and it is considered at this time to have no link with vaccine induced cancer. This is the only type of vaccines that should be used in cats. If your cat has been vaccinated for feline leukemia with a Merial recombinant vaccine you will know it because of the special VetJet injector that is used. It is a teal and white 7-8 inch device which emits a large popping sound.Also as cats age, they become naturally resistant to FeLV anyways. However for all other vaccines, Merial's non-adjuvanted vaccines in my opinion are the only way to go.
There was a question on this in our VIN (Veterinary Information Network). Here is an answer by Dr Alice Wolf who is one of the most knowledgeable veterinarians I know. Here is her answer to a question on this:
">>> Is there any new evidence regarding non-adjuvanted vaccines in cats and whether they are really less likely to cause reactions <<<
The major issue is the post-vaccinal inflammation that occurs with adjuvanted vs non-adjuvanted vaccines and the induction of malignant transformation that can lead to vaccine-associated sarcomas.
Here is an abstract of a recent study demonstrating the reduced local reactivity of non-adjuvanted vaccine:
Vaccine. 2007 May 16;25(20):4073-84. Epub 2007 Mar 7. Links
A kinetic study of histopathological changes in the subcutis of cats injected with non-adjuvanted and adjuvanted multi-component vaccines.Day MJ, Schoon HA, Magnol JP, Saik J, Devauchelle P, Truyen U, Gruffydd-Jones TJ, Cozette V, Jas D, Poulet H, Pollmeier M, Thibault JC.
School of Clinical Veterinary Science, University of Bristol, Langford, BS40 5DU, United Kingdom.
m.j.day@bristol.ac.uk
The aim of this study was to investigate the subcutaneous tissue response to administration of a single dose of multi-component vaccine in the cat. Three groups of 15 cats were injected with one of three vaccine products with saline as a negative control. Cats in group A received non-adjuvanted vaccine; cats in group B received vaccine with a lipid-based adjuvant; whilst those in group C were vaccinated with a product adjuvanted with an alum-Quil A mixture. The vaccine and saline injection sites were sampled on days 7, 21 and 62 post-vaccination. Biopsies of these vaccine sites were examined qualitatively and scored semi-quantitatively for a series of parameters related to aspects of the inflammatory and tissue repair responses. These data were analysed statistically, including by principal component analysis. At all three time points of the experiment, there was significantly less inflammation associated with administration of non-adjuvanted vaccine (p=0.000). Although there was evidence of tissue repair by day 62 in all groups, those cats receiving adjuvanted vaccines had evidence of residual adjuvant material accumulated within macrophages at this late time point. The severity of tissue reactions may vary significantly in response to vaccines which include adjuvants or are non-adjuvanted.
>>> I am reevaluating our protocols and considering going back to using 3 yr feline rabies. <<<
On the basis of this information, I hope that you will continue to use only non-adjuvanted products in cats.
Alice"
-Alice M. Wolf, DVM, DACVIM, DABVP