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Until
relatively recently, canine herpes seemed to be a problem only
in the whelping boxes maintained by rank novices in breeding
dogs. Experienced breeders could control it, prevent the
effects. But it appears that perhaps a different strain of virus
is running rampant and causing more and different problems for
breeders. From the website www.canineherpes.com
comes the comment “Canine herpes virus … has been largely
forgotten for many years, due in part to the difficulty in
making a definitive diagnosis. However, it is becoming
increasingly clear that the virus causes many more problems than
was first thought.” They were speaking mostly of the
fading-puppy syndrome where entire litters die off, one pup at a
time, in the course of a day or two at most.
Herpes
is caused by a virus. Demodectic mange is caused by the action
of a parasitic mite on the dog that has a weak immune system.
Alike as night and day, you might think, but there are one or
two similarities: some dogs are more resistant to such attacks
than others, and the causative or triggering culprits are almost
everywhere. A close similarity in control and resistance is in
the response to other antigens, such as hookworm, coccidiosis,
and even parvo. None of these is an automatic death sentence if
the dog is an adult or adolescent, and is otherwise healthy. The
very young and the very old are less able to fight off new
microbial or parasitic attacks. The more such stresses are put
on these individuals, the worse the prognosis. I have seen
puppies die of combinations like coccidiosis and hook, when they
would have survived if only one of those had been present. I
have seen adults exposed to parvo for the first time and come
through the ordeal just fine. But combine the threats, or aim
them at the age extremes, and mortality rates become very high.
What
I meant by the omnipresence of antigens is that Demodex mites,
for example can be found on perhaps well over 90% of dogs and a
big percentage of humans. (One researcher said, “This disease
can literally be carried home on your clothing.”) It’s like
dust or pollen… everywhere. But with an immune system
not up to par, and a combination of stress factors, and you have
dangerous, even fatal consequences. I once bought a bitch puppy
for my mother. The pup developed severe generalized demodecosis
— so bad that all attempts at control failed, and she had to
be euthanized. Oestrus is by far the most stressful trigger for
demodicosis. Herpes virus, though an entirely different
organism, also exists on or in nearly all animals, including
probably a transient and harmless guest on humans. However, we
therefore could transmit the virus to our dogs. Virus
particles do not live forever in non-nutrient (host)
environments, but long enough to be carried to the ultimate host
on clothing, by sneezes, etc. It is the immune-challenged
weakened pup that would fall to its onslaught. One difference
between Demodex and Herpes is that the mite is alive and active,
though ineffective against a healthy dog; herpes virus microbes
enter a dormant state and are “awakened” by various
stresses. Merial says, “Most animals have already been
exposed. Although it can be spread at mating, it is much more
likely to be spread by simple contact.”
According
to an Australian website, and an article by Dr. Mary Wakefield,
“Puppies die of Herpes only so long as they are unable to
mount a fever response, or have the lower body temperature of
neonates. After 3 weeks of age puppies can raise their
body temperatures high enough to resist the overwhelming
infection which results in death. The treatment for Herpes
in young puppies with the appropriate signs is elevation of the
body temperature. Check with your veterinarian if you
think this may be the problem in your litter under three weeks
of age.” The problem with that advice is that by the
time one has a clue to the presence of the disease (the first
dead or dying puppy), it is too late. The others are likely to
have been just as chilled during a period of exposure to the
virus. And in weakened pups, the virus can replicate like
wildfire.
Unfortunately,
the Wakefield piece, while very helpful overall, has some minor
problems. For example, she states, “The best way of preventing
newborn puppies from acquiring the disease is to quarantine them
and their dam from 3 weeks prior to birth and 3 weeks after
whelping.” If the virus is everywhere, as it almost always is,
that is no solution. There are only two ways (1.5, really) that
I have confidence in to prevent neonatal deaths from herpes:
elevated ambient temperature during the first three weeks, and
the possibility of the Merial vaccine (but still, I would not
lower the thermostat!). Wakefield says, “Herpes infection of
the dam which does not result in abortion may result in low
birth weight, weak, or stillborn puppies.” And, she says
that titres show herpes activity in 80% of bitches who had lost
their litters, even though there was no bacterial blame.
Wakefield advocates isolation, but I believe that’s a lost
cause; Merial states, “The virus does not come from bad
kennels – it is already everywhere!”
Since
immunity is very short-lived, contracting the problem again and
again is to be expected. Dogs have fluctuating titre levels all
the time, some of it due to new exposures, some due to
stress-released previously dormant particles.
In
the next few paragraphs, I will quote from my book, The Total
German Shepherd Dog http://www.Hoflin.com
and give you what we used to know about it. Then I will return
to some of the reports and difficulties that exist early in
2004. I certainly hope they will be resolved by year’s end!
Herpes
— There are many organisms in the virus family called herpes,
the most common in dogs being the puppy killer at ages of around
two weeks or less. Herpes seems to be present in most dogs most
of the time, but some pups are more susceptible or under more
stress, which lowers their resistance. New puppies that are not
given adequate drying, heat, and nursing opportunity (internal
warming) right after delivery are most at risk. Once the disease
has been noticed in a litter, few survive. Prevention is the
only remedy in nearly all cases. It is practically unstoppable
once noticed.
Neonatal
deaths and Herpes viremia — This syndrome, caused by a herpes
virus, is a major cause of death in pups between five days and
three weeks, and may take two weeks to spread through the
litter. “Herpes” actually refers to a class of several
viruses, so you may encounter the word used in the context of a
human disease, or a disease in other animals. One of this class
will not produce the same disease as will another. With this
viremia, death from kidney and liver failure usually occurs
within eighteen hours; symptoms include constant crying, shallow
and rapid breathing, loss of appetite and coordination, and a
soft, yellowish green stool with no particular odour. The stool
symptom can be easily missed if the bitch is cleaning her pups
to make them defecate.
Treatment
includes elevating the environmental temperature, thus creating
a sort of artificial fever since fever is one of nature's ways
of fighting virus organisms. Close to one hundred degrees F (38
C) for the first three or more hours post-parturition is a
recommended ambient temperature, followed by 90 to 95 degrees
for another 24 hours. Some people who have worries about the
drying-out effect of such high temperatures frequently give the
pups glucose solution and formula to prevent dehydration, but I
have had hundreds of puppies born to my bitches without that. I
just make sure that the floor is warm or insulated, and the heat
lamp, heating pad, or low-hanging light bulb is on when the dam
is going out to “potty” for the first weeks. Herpes thrives
even as high as between 91 and 98.6 degrees F (33 to 37 degrees
C), and chilled pups are especially susceptible. At 100 or 101
degrees the virus stops replicating, so the object is to get the
pup's body temperature up to that which is considered normal in
the adult, about 102 degrees. After three weeks of age,
the pup's body temperature is usually high enough to prevent
herpes growth, and by then they have developed the shiver
reflex, which is another heat-regulating mechanism. However,
because damage to kidneys may not produce symptoms until as late
as ten months of age, perhaps the surviving pups (in a litter
with pups known to be dying of hypothermia -exacerbated herpes)
that show the crying symptom associated with haemorrhage and
necrosis should be euthanized right away. Ask your veterinarian
about treatment with a preparation, Vira A, designed for human
herpes encephalitis, or he may have more recent advances. But I
have not seen any good results from any kind of treatment. A few
pups will survive now and then, but regardless of treatment
(other than elevated temperature).
This
virus can remain latent for many months and be reactivated by
stress or an immunosuppressive agent such as a shot of cortisone
or similar steroid. Thus, pups that contract a marginal
infection but not enough to be fatal, might still have their
immune system weakened, or else harbour the inactive virus. Pups
seem to get the virus through the saliva of their infected dam,
though a few may contract it in the birth canal or even in the
uterus before birth. If you have a kennel in which two or more
bitches are producing litters and one loses a litter to herpes,
what should you do to save the next litter? Besides the usual
step of cleaning everything with a dilute bleach solution (as
with parvo or other viral infections), you may find success by
having your veterinarian inject them with serum obtained from
the bitch that lost the litter. You may also succeed by keeping
them in the high temperature environment mentioned above.
That
was the state of our knowledge in the last couple decades of the
20th Century. We had come only so far as determining that herpes
had about 90% mortality in neonates. Now we may be on the
brink of an advance in knowledge, unfortunately brought on by an
alarming increase in failures in the dog breeding community. For
some 10 or 15 years, I have been hearing more and more
complaints about bitches not conceiving. And this is a day when
companies like Synbiotics can help us zero in on the exact best
time to inseminate. Progesterone, LH, and other hormones can be
tracked with simple and fast test kits, and give far better
accuracy than the vaginal cytology (study of the changing shape
of cells lining the uterus) or the physical activity of the
bitch or even the most jaded or experienced stud dog.
At
least in the German Shepherd world, many of us have been blaming
the fact that so many of our bitches were “coming up empty”
on the known use of anabolic steroids given to many of the top
show dogs in an attempt to boost their chances of being placed
in the very highest positions at the annual national specialty,
or even the preliminary competitions where success is considered
in making judging decisions at the final big show. There is no
doubt that this goes on, and we know that many of the top human
athletes in weightlifting, football, boxing, track, etc. are
sterile or temporarily have a low sperm count.
But
now, there may be another factor. Herpes appears to be the cause
of many or most of these missed matings. Nobody has been keeping
statistics, so we can’t tell how many failed breedings are
costing bitch owners money and time. While a few German clubs
like the SV (for GSDs) will make note of such complaints, and
withdraw rights from males that are shooting blanks, they will
not hear from most disgruntled breeders. Stud dog owners are
racking up the fees and bitch owners are getting poorer.
Correspondents in England and Australia tell me it (failure to
conceive) has been going on in their countries for some time, as
it has in the U.S. Recently, reports have come out of New
Zealand and other far-flung places. “Coming to a theatre near
you!” Freight and air regulations are prohibitive, “Homeland
Security” has much adverse fallout, and even if you can get
them, delayed repeat breedings are a drain on the pocketbook.
Most Germans will not give you more than the time of day after
you twist their arms for a second breeding if the first did not
take.
The
increasing use of too-frequent vaccines for any and all things
is another target for blame for lack of conception and other
concerns. That is, some want to point the finger at the effect
of over-vaccination on the immune and other systems. Fewer
people have other causes they want to point the finger to, but
it is a definite fact that greater numbers of people are not
getting their bitches pregnant. Perhaps the new factor in the
well-known but poorly documented rise in number of failed
matings is a new herpes variety. Europe seems to have found out
that it is real. In many growing pockets on the continent,
breeders are using and reporting success with a new vaccine. In
England, for example, friends tell me of scores of bitches
supposedly infertile or nearly so have been producing very well
after getting the vaccine. The word going around there is that
if the bitch is vaccinated while in oestrus or right after the
bitch is mated, and again at 6 or 7 weeks in whelp, not only is
it almost always successful, but larger litter numbers than
expected seem to be the norm.
Right
now, I know of only one company making the herpes vaccine,
Merial. They have said that [rough translation]: “the herpes
canine virus is an infectious and contagious disease caused by
alpha herpes virus, which involves reproduction disorders,
losses of pups mainly before 3 weeks, but also of infertility,
abortions, and/or stillbirths. The vaccination which exists is
used to protect the pups less than 3 weeks at which age one
finds the clinical form most serious. The mothers receive an
injection at the time of heats [oestrus] and another injection
one or two weeks before whelping. This is thus addressed
especially to the professional breeders as well as to
amateurs.”
Merial
also says, "Visit www.canineherpes.com
for comprehensive public domain info." and
describes the virus and vaccine thusly: “EURICAN Canine
herpes virus (F205) strain antigens; Indication: Active
immunisation of bitches to prevent mortality, clinical signs and
lesions in puppies resulting from canine herpes virus infections
acquired in the first few days of life.”
Merial
is headquartered in Belgium, but has done much if not most of
its business in France, although national borders in Europe are
getting indistinct. French breeders I hear from tell me they are
convinced the new herpes strain is the real cause of bitches not
getting pregnant as well as a reputed increase in mummy puppies,
absorbed foetuses, spontaneous abortions, stillbirths, and
neonate mortality in the first three weeks. Whether this will be
substantiated by scientific studies, I cannot forecast, but I am
told that the herpes incidence there (France) in GSDs is now
about 40%, and expected to rise to 80% in 2005. I know I have
been mostly unsuccessful in getting bitches bred in the past few
years, and I hear the same complaint from many, many others
around the world.
The
virus is not yet available in the U.S. Drug companies are not as
aware as they should be, or they know something they aren’t
telling us. Perhaps they don’t want to buy licensing rights to
make it here, which is not likely, because they could (and do)
pass along those costs with their huge profits, to the selling
price to the vets and ultimately to you. Many people would urge
every breeder to get their brood bitches vaccinated during her
oestrus period and some say a booster before whelping. But
American vaccine manufacturers are behind the wave on this one.
The suggestion that breeders have some vaccine Fed-Ex'd or
UPS'd direct from Europe to your refrigerator is nice on the
surface, but the U.S. Customs Bureau (now under control of the
Homeland Security Agency) does not allow “biological agents”
to be shipped to individuals. Let's hope the U.S. medical supply
houses get on the ball right away on this, because the few
bitches that are benefiting (if indeed it works as Europe
claims) are getting their vaccines smuggled in (undeclared in
the luggage of people coming from Europe). That’s a risky way
to get what you need, and would probably carry a greater penalty
than what might be placed on grey-haired seniors bussing to the
Canadian side of the river to get decent prices on their
prescription drugs.
There
are other causes for non-conception, of course. One person wrote
me recently about the inability to get Boston Terrier bitches
pregnant, and being just about to give up breeding. A
friend suggested that she “do a sensitivity test for bacteria
near the uterus, and she did and put her dogs on an antibiotic.
(Amoxicillin wasn't doing the job.) I believe that they were put
on Baytril. Since she began treatment she now has three
very pregnant bitches.” But E. coli and other bacteria,
while almost as omnipresent as Herpes and Demodex, is relatively
seldom the culprit.
Merial
information tells us, “Like all herpes viruses, CHV is highly
infectious, and a recent study showed that more than 80% of the
dogs tested had been exposed to the virus at some time in their
lives. Other studies have shown infection rates of 40-100% in
kennels around Europe.” They also note, “Once the virus
becomes established in kennels, periods of high mortality are
interspersed with a general fall in the average birth weight of
the litter” and “the existence of a problem only becomes
apparent once a vaccination programme is put in place.”
The
“epidemic” (not really an accurate term here) is going to
get worse before it gets better. Drug supply firms in the U.S.
and other countries need to determine if indeed, the conception
failures are due mostly to the virus, and that they had best get
with the program and serve their customers! The AVMA and
others need to address this fatal problem rather than meddle
with the long tradition of tail docking with its two seconds of
discomfort. While only a few mentions in Merial’s promotional
literature (and zero professional journal articles so far)
involve “infertility affecting several bitches”, one
suggestion under their “treatment” guidelines is simply,
“Try the vaccine and see what happens”.
To
the question, “If the bitch is already pregnant, is there any
point in vaccination?”, they respond in the affirmative: “If
possible, try and give two injections, even in the last few
weeks of pregnancy. Even one injection is beneficial, though
obviously the later it is given the greater the chance that the
placenta will be damaged and the unborn puppies affected.”
Here again, the emphasis is mostly on the health of puppies
already conceived or whelped, not so much on the failure to
conceive. That is only brushed lightly.
My
advice is to put pressure on the drug suppliers, veterinary
colleges and AVMA to get the straight facts about the effect of
herpes virus on conception failures; then, if there is
confirmation of the anecdotal evidence, quickly make a vaccine
available to breeders. We have already lost enough!
©
2004 FL
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