From:
sukiec@optonline.net
Date: 2005-04-02 18:03:18 UTC
Subject: Re: [ferrethealth] Delayed "distemper" booster WAS: Delayed Parvo booster---told we have to ''start over'' ??
To: ferrethealth@smartgroups.com
Message-ID: <5765915.1112464998568.JavaMail.root@thallium.smartgroups.com>
When the ferrets are young their immune systems are not well enough develop=
ed for them to have a long lasting effect which is why the shots are repeat=
ed within 2 to 3 weeks of each other. According to one of the vet texts I =
have (_Biology and Diseases of the Ferret_) in research facilities where fe=
rrets may be acquired younger from one of the several places that supply to=
research and where there may be an increased risk of exposure as many as 5=
canine distemper shots may be used during kithood. After something like 1=
2 to 14 weeks (Can't recall exactly offhand) the immune system is old enoug=
h to form good protection from the CDV vax but it appears that the kit need=
s to be a few weeks older to form good protection from the rabies vax (See=
the requirements in the Compendium of Animal Rabies Control and Prevention=
in the AVMA site.).
Vaccines can vary. I have heard an off-record report of a conversation wit=
h the maker of one of the older CDV vax used on ferrets that after a given =
age one of their vax may be enough for the first year but it is not documen=
ted well enough for them to say so formally yet. I have NOT heard of that =
same statement from others.
Think of humans with vaccines: some types last only a short time, others ma=
y go several years but have a lot of variation among people depending on ag=
es and other factors (for example, the pneumonia vax). Some last about 10 =
years (tetanus), others last about 15 (small pox), some last close to twent=
y (and then you hear of outbreaks of childhood diseases on some campuses), =
and some go much longer.
Not only do vaccines vary by type of disease involved, they vary with vacci=
nes for the same disease. When rabies vaccines were first being tested on =
ferrets, of those which did work there was one that provided protection for=
only 6 months (pers. com. Judi Bell many years ago). That vax was not pur=
sued for further study in ferrets.
They vary, too, with how much vaccine is used and how the vax is given, wit=
h a technique which puts vaccine between skin layers being more effective f=
or lower doses (because the immune system is more active in the right way i=
n those tissues), but this type of shot is much harder to give and many sim=
ply can't give them. (I've also personally noticed in the ones we have used=
at home that human needles seem to be sometimes longer but always much sha=
rper than the ones sold for vet use so that could maybe make a tricky techn=
ique all the harder to do.) This is a technique which is beginning to be m=
entioned as a way to immunize some of those humans who have reactions and a=
lso the elderly who tend to have a poorer response to vaccines. There were=
some neat scientific articles published on it last year.
These days almost no vaccines are grown in eggs. Influenza vaccine is the =
exception. It is a harder and more expensive manufacturing process which c=
arries an increased risk of allergic reaction sometimes BUT the Canine Dist=
emper vaccines which were grown that way for dog use were tested in ferrets=
and they lasted for a very, very long time, some as long as almost a full =
ferret lifetime. =
In contrast, there have been cases of canine distemper in households and sh=
elters where some of the ferrets had previous vaccinations, and unlike the =
ferrets used for testing the avianized (egg grown) earlier vaccines there h=
ave been ferrets who were vaccined something like 2 to 3 years before who d=
id have central nervous system damage from the disease and took a lot of ca=
re to survive it. (Unvaccinated ones died virtually always.) So, until th=
ere are tests of what titer levels effectively predict enough protection it=
is something of a crap shoot to try going too long between vaccinations. =
Hopefully, it will eventually turn out that they can go something like 1 an=
d 1/2 to 2 years (and I sure would not complain about an even longer interv=
al) between CDV vaccines and maybe even rabies vaccines but unless there is=
a new released study from a vet school or someplace else reputable there i=
s no testing that can at this point reliably say what kind of interval long=
er than a year is safe enough for them. So, it is taking a risk to delay v=
accines too long.
Remember, too, that for the rabies shots currently the protection of the Co=
mpendium of Animal Rabies Control and Prevention and how states observe it =
lasts for only a year after each vaccine of IMRAB 3. Ferrets are not the o=
nly animal considered to be getting only one year from that vaccine at the =
current state of knowledge, but many others have had testing which shows 3 =
years of coverage for their species.
In studies of Canine Distemper in ferrets if you immunize at least most of =
the ferrets (I think it was something like 75 to 85% but that is going fro=
m memory) in a large colony the disease dead-ends usually instead of spread=
ing. On the other hand if the disease begins in a colony which has no vacc=
ine protection then vaccines are used almost no animal survive, probably du=
e to the timing of when the disease is present but still silent.
=
=
End of ferrethealth Digest
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