Cats: Exposure to Rabies

One of the most contentious topics in any cat group is the subject of vaccines and whether are not to vaccinate.  Often someone will remark that they have to vaccinate because of the local law.  Some people are unaware that the requirement for rabies vaccination depends on the locality.  Where I live, rabies vaccinations are required by county law for dogs only.  I have friends who live in areas where rabies vaccinations are also required for cats.  The variation in requirements depends in large part on the incidence of rabies in wildlife in an area.

Please keep in mind that the rabies vaccine is NOT for the health of the dog or cat, but to protect humans from the rabies.  This article, Rabies Postexposure Prophylaxis, by M. Gayne Fearneyhough, BS, DVM (p 557-572 in Vol 31, No 3, Vet. Cl. of NA: Small Animal Practice, May 2001) looks at the treatment of humans after they have been bitten by a potential rabid animal.  As I do not particularly care about human medicine, this is a very brief summary.

One statement of interest in this article is "many parts of the western United States are free of terrestrial rabies", which, if you look at the 2010 CDC map for rabies infections in dogs and cats, my area, southern CA, has no cases (despite heavy testing) whereas a state like Pennsylvania is solid yellow in the east.  This explains why my Eastern friends are so adamant about rabies vaccines and here it's a minor concern.

The chart below is the decision tree recommended for humans:

Perhaps the most interesting section had to do with post-exposure treatment in domestic animals.  I have lived under the assumption that if a cat was bitten, that was a death sentence.  Apparently not.  At least 2 studies, one of 713 animals and another of 632 animals (dogs, cats, cattle, horses, sheep, goats, pigs, and 1 llama) were treated.  The first study had a 99.7% survived and 99.5% in the second.  So, yes, a cat bitten by a rabid animal CAN be successfully treated. The main problem mentioned is that the animal may survive but may not be free of rabies. I would think a second problem is to find a place that would quarantine the cat and provide treatment for several weeks.

Cats: Vaccine-Related Sarcomas

This was a relatively short article and one topic, thankfully, that I have never experienced.  Since many of my cats do come from unknown backgrounds, I do suspect that some are at risk, but so far, so good. 

Recent Advances in the Treatment of Vaccine-Sarcomas, by Gregory K. Ogilvie, DVM
p 525-533 in Vol 31, No 3, Vet. Cl. of NA: Small Animal Practice, May 2001...

The article focuses on the diagnosis and treatment of the sarcoma and not on the fact that vaccines seem to cause sarcomas.  The latter is assumed by the article. The article doesn't mention, but from other sources the sarcomas are linked primarily to FeLV and rabies vaccines.

Physical exam -- The sarcoma appears as a lump or thickening either at the injection site or, interestingly, on the underside of the cat (migration of vaccine agent).  The lump can appear from days to years afterwards. This timing, days to years, is a bit scary since I do not know the vaccine history of many of my cats.

Evaluation -- The first step is a needle biopsy to confirm that it is a sarcoma.  The next step is xrays to determine if it has metastasized.  Enlarged lymph nodes may need to be biopsied.

Treatment of small tumors -- The recommendation is for a 2cm cuff around the tumor and 1 skin layer deeper.  2cm on both sides is HUGE!  The author mentions the inconclusiveness of both chemotherapy and radiation therapy, and from other sources, this does not seem to have changed significantly in recent years.

Treatment of large tumors -- The author recommends surgical reduction of the tumor followed by radiation treatment.

Metastatic sarcomas -- Chemotherapy seems to be the solution but at the time of writing there was no clear recommendations.

Patient Management -- The author stresses the need to give the client pain meds, anti-nausea meds, and appetite stimulants to help the cat.  Also, the client should be given written instructions and educational material because owners often are very upset when told their cat has cancer.

Prognosis -- For small, non-metastatic tumors, the prognosis is good.  Otherwise, the outcome is usually not good as the tumor recurs.  Who does the surgery and how extensive it was drastically influences the outcome:

"The median time of tumor control was 94 days.  Median tumor control for tumors treated with excision performed at a referral institution (274 days) was significantly longer than that for tumors excised by a referring veterinarian (66 days).  A radical first excision yielded significantly longer median tumor control (325 days) than did a marginal first excision (79 days)..... Few cats (13.8%) receiving only surgical treatment had long-term (>2 years) survival, suggesting that radiation and chemotherapy are highly indicated as adjunctive therapies."  And this is an interesting statement about radiation and chemotherapy given what the author said previously about the inconclusiveness.

These vaccine-related sarcomas are the reason the new vaccine protocols recommend vaccinating for rabies and FeLV in the legs or even tail -- those parts can be amputated to save the cat from the sarcoma.  To me this is very drastic and makes me ever so grateful that I don't have to vaccinate for rabies of FeLV.