Re: opinions on fcvrp vaccine
That last post was very rushed but see below for more details.
This is a very important subject for me since the last person I want is to be perceived as is.... the 'Andrew Wakefield' of the veterinary community.
First, an excerpt from my website taken from CSU:
"The Center for Companion Animal Studies at Colorado State University has shown that cats vaccinated with FVRCP vaccines grown on Crandell-Rees Feline Kidney (CRFK) cell lines can develop antibodies to renal (kidney) proteins, and that cats hypersensitized to CRFK cell lysates can develop
interstitial nephritis.
The immunodominant antigens to which antibodies are formed in these cats are α-enolase and Annexin A2, both of which are linked to autoimmunity and renal disease in humans.
Recently, we have shown that cats administered FVRCP vaccines parenterally (i.e. injectable) have higher levels of circulating antibodies to these antigens than do cats who were administered a FVRCP vaccine via intranasal administration."
Now...in plain English:
The viruses used to make vaccines need to be grown in what is called a "cell culture". The cells used to make the FVRCP vaccine are feline (cat) kidney cells.
When these kidney cells are injected into the cat (along with the vaccine), his immune systems views them as foreign and makes antibodies against them. Unfortunately, those antibodies don't know the difference between the injected kidney cells and his own kidney tissue resulting in an autoimmune 'attack' on his own kidneys. ('Auto' means 'self''.)
Most people have heard of Lupus. Lupus is a life-threatening autoimmune disease most commonly seen in humans. So, in essence, the FVRCP vaccines stimulate a Lupus-like reaction in the recipient.
End excerpt from my website.
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See page 2 from this paper by Dr. Lappin - from CSU:
Note that "interstitial nephritis" means kidney inflammation.
http://secure.aahanet.org/eweb/images/A ... ACCINE.pdf
See below for excerpts for people who do not want to wade through the whole thing - with my comments in italics:
Dr. Lappin:
In my opinion, vaccines for cats undoubtedly have saved many more cats than they have hurt.
We can obviously all agree on that statement.
Regarding injection site sarcomas:
Previously, this problem seemed most apparent in cats administered adjuvanted rabies virus and feline leukemia virus vaccines. However, recent information suggests that injection site sarcomas can occur with any type of vaccine. For example, in the United Kingdom in 2005,
23 of 39 injection site sarcomas reported in cats occurred at the site a live vaccine (non-adjuvanted) was administered (Dyer et al. 2007).
I harped very heavily on adjuvants on my Vaccine page but it is important to note that even the non-adjuvanted FVRCP vaccine and the PureVax vaccines can cause nasty sarcomas.
The Crandall-Rees feline kidney (CRFK) cell line has been used to propagate feline viruses for years. While isolated from a kidney, the cell line has characteristics of a fibroblast. During virus purification for vaccine production (FVRCP) or immunoassay development, it is impossible to remove all CRFK proteins or other cell constituents. Thus, CRFK proteins contaminate the viral preparations, and commercially available FVRCP vaccines grown on the cell line contain CRFK proteins.
As a consequence, during the course of routine immunization, cats are exposed to CRFK proteins and may mount an immune response against those proteins. Since the CRFK cell line is derived from a feline cell line, administration of FVRCP vaccines induces antibodies that also bind to feline tissues.
Antibody/antigen (cell) complexes are not a good thing to have in tissues.
We have now performed several studies to assess the problem.
My summary for those not wishing to wade through the article:
In 2005 they conducted a study to test for antibodies to the CRFK cell line (the feline kidney cell culture line used to grow the virus line) and also to test for antibodies to FRC (feline renal cells).
Quote:
All 6 cats administered CRFK lysate were positive on multiple sample dates in the FRC ELISA.
All 6 cats administered a parenteral vaccine were positive on multiple sample dates in the FRC ELISA.
("parenteral" means injectable vs intranasal)
Significant CBC, serum biochemical, urinalysis, microalbuminuria, or histopathologic abnormalities were not detected during the study.
ie....no clinical or histopath signs of renal disease were noted - but note that they did the biopsies 6 weeks after the last vaccine and they only followed the cats for 1 year. They then went back and repeated the study but this time they took the biopsies within 2 weeks of the last vaccine.
Quote:
In the first study, renal biopsies were collected 6 weeks after the last vaccination or hypersensitization (Lappin et al., 2005). It is possible that inflammation of renal tissues occurred but was transient and resolved by the time of biopsy.
We have completed a follow-up study (Lappin et al. 2006a) in which we hypothesized that
interstitial nephritis would be detected in cats hypersensitized with CRFK lysates, boosted with CRFK lysates, and then biopsied 2 weeks after the booster.
We documented interstitial nephritis (kidney inflammation) in 3 of 6 cats hypersensitized with CRFK lysates, but not cats vaccinated with the intranasal FVRCP vaccine. None of these 3 cats had significant inflammation detected 1 year previously.
One of the 6 cats recently died of interstitial nephritis.
However, it is important to emphasize that the cats in the study had been inoculated multiple times with CRFK proteins over the first year of the study. Whether this occurs after parenteral administration of CRFK-contaminated FVRCP vaccines using routine vaccination protocols remains to be proven.
We are in the process of determining the immunodominant CRFK antigens recognized by feline antibodies (Whittemore & Lappin 2005). We have identified 3 immunodominant antigens and will study these antigens further.
Antibodies against 2 of the 3 antigens have been associated with autoimmune disorders in people.
At this time, we have not directly linked FVRCP vaccination to auto-immune diseases in cats.
**Note that the first study only lated 1 year and used a very small sample size.
**Note that the word "diseases" in the sentence above means, to my interpretation, an overt clinical manifestation of disease. In other words, the patient now feels/looks sick.
However, there is a section on my main page that speaks to this issue. It is at the top of my Feeding Your Cat article that talks about the fact that we are all 'fine'...CLINICALLY....until we are not so fine.
In other words, long before we feel sick.... or see that cancer..... or experience clinical signs of ANY illness such as kidney disease, diabetets, etc., damage is being done under the radar - at the cellular level.
The minute we start to *feel* sick is not the same time that our body started getting sick. We start getting sick - at the cellular level - long before we started to feel sick.
In a summarized nutshell, what Dr. Lappin's studies have show is that the FVRCP vaccine does cause interstitial nephritis.
The $64K question is - what role does this kidney inflammation play in the pathogenesis of feline CKD?
I am certainly relieved that fewer people are subjecting their cats to annual vaccines but a poll (not sure how long ago) showed that almost half of all vets are still pushing annual vaccines!
More from Dr. Lappin's paper:
To further assess for disease associations with administration of CRFK-containing FVRCP vaccines, we are currently performing the following studies:
1. determination of the source and distribution of CRFK proteins in feline tissues; and
2. correlation of CRFK antibodies with presence of biochemical abnormalities in a group of client-owned cats in the United States.
I assume that "biochemical abnormalities" means elevated BUN, creatinine, etc.
A general recommendation at this time would be to
not use parenteral FVRCP vaccine at an interval shorter than every third year.
Pay close attention to how that is worded. They are NOT recommending to vaccinate your cat every 3 years! This is a huge mistake that people make when they talk about the "3 year protocol".
They are saying "don't vaccinate more frequently than every 3 years". Very, very open-ended.....
In addition, FVRCP antigens should not be split and given yearly, as that may result in increased exposure to the cell culture antigens.
End excerpts Dr. Lappin's paper
Like with so many things in life, we have to do a risk:benefit analysis and then be comfortable with our decisions.
Most owned cats are at a very, very low risk for panleuk.
But having said that, do not equate a higher risk with a lower duration of immunity. In other words, if you take two cats with an equal immune response to the same vaccine protocol..... the cat wandering around out on the street is no less protected than the house cat that is at a much lower risk. All things being equal, they should have the same level of antibodies and memory cells.
The other $64K question is.....does further boostering really increase the cat's immunity??? The answer to that is not a clear-cut "yes". It may or it may not.
And...the ol' ECID is a factor also.
One thing that we have also not discussed is running a panleuk titer. This post has already gotten too long and I discuss titers on my Vaccine page.
Bottom line? Educate yourself and then do whatever makes you comfortable since there are few absolutes in this world.
[We'd be talking about not vaccinating at all, of course, since the antibodies would be created from a single shot just as from multiple shots.]
