 |
Canine
distemper is a contagious and serious viral illness with no known cure. The
disease affects dogs, and certain species of wildlife, such as raccoons,
wolves, foxes, and skunks. The common house pet, the ferret, is also a carrier
of this virus. It affects many areas of your
dog's body and it is highly contagious. In approximately half of the cases, it
is fatal.
The disease
is highly contagious (via inhalation) and fatal 50% of the time, thus making it
the leading cause of infectious disease death in dogs. The virus infects the
gastrointestinal tract, respiratory tract, the brain, and spinal cord.
Young puppies, between 3 and 6 months of age, are
most susceptible to the disease and are the most likely to die from it.
However, non-immunized adult dogs are also highly susceptible to distemper.
These older dogs often develop mild cases.
The virus that produces canine distemper belongs to
the paramyxovirus group. Human measles virus is also a member of this group.
Distemper virus is easy to kill with disinfectants, sunlight or heat.
Symptoms
Common
symptoms can include:
1) High
fever,
2)
Watery discharge from the eyes and nose,
3)
Vomiting and diarrhea,
4)
Hardening of the footpads and nose,
5)
Seizures (of any part of the body, but seizures that look as if the dog is
chewing gum are unique to distemper),
6) Paralysis
 |
Gastrointestinal and respiratory signs
Commonly observed signs are a
runny nose, vomiting and diarrhea, dehydration, excessive salivation, coughing
and/or labored breathing, loss of appetite, and weight loss. When and if the
neurological signs develop, incontinence may ensue.
 |
| Dog infected with canine distemper: Note the purulent nasal discharge and hyperkeratotic nose. |
Neurological signs
The signs within the central
nervous system include a localized involuntary twitching of muscles or groups
of muscles, seizures often distinguished by salivation, and jaw movements
commonly described as "chewing gum fits", or more appropriately as
"distemper myoclonus". As the condition progresses, the seizures
worsen and advance to grand mal convulsions, followed by death of the animal.
The animal may also show signs of sensitivity to light, incoordination,
circling, increased sensitivity to sensory stimuli such as pain or touch, and
deterioration of motor capabilities. Less commonly, it may lead to blindness
and paralysis. The length of the systemic disease may be as short as 10 days,
or the start of neurological signs may not come until several weeks or months
later. Those few that survive usually have a small tic or twitch of varying
levels of severity. With time, this tic will usually diminish somewhat in its
severity.
Lasting signs
A dog that survives distemper
will continue to have both nonlife-threatening and life-threatening signs
throughout its lifespan. The most prevalent nonlife-threatening symptom is hard
pad disease. This is when a dog experiences the thickening of the skin on the
pads of its paws, as well as the end of its nose. Another lasting symptom
commonly is enamel hypoplasia. Puppies, especially, will
have damage to the enamel of teeth that are not completely formed or those that
have not yet grown through the gums. This is a result of the virus killing the
cells responsible for manufacturing the tooth enamel. These affected teeth tend
to erode quickly.
Life-threatening signs usually
include those due to the degeneration of the nervous system. Dogs that have
been infected with distemper tend to suffer a progressive deterioration of
mental abilities and motor skills. With time, the dog can acquire more severe
seizures, paralysis, reduction in sight and incoordination.
These dogs are
usually humanely euthanized, due to the immense pain and suffering they face.
 |
 |
Progression..
Once these pets are infected, the virus is shed in
all their body secretions
Puppies
from three to six months old are particularly susceptible. CDV spreads through aerosol droplets
and through contact with infected bodily fluids, including nasal and ocular
secretions, feces,
and urine, six to 22 days
after exposure. It can also be spread by food and water contaminated with these
fluids.The time between infection and
disease is 14 to 18 days, although a fever can appear from three to six days
after infection
The
virus first appears in bronchial lymph nodes and tonsils two days after
exposure. The virus then enters the blood stream on the second or third day.A first round of acute fever tends to
begin around three to eight days after infection, which is often accompanied by
a low white blood cell count, especially oflymphocytes,
as well as low platelet count. These signs may or may not be accompanied by anorexia, a runny nose, and discharge from the eye. This
first round of fever typically recedes rapidly within 96 hours, and then a
second round of fever begins around the 11th or 12th day and lasts at least a
week. Gastrointestinal and respiratory problems tend to follow, which may
become complicated with secondary bacterial infections. Inflammation of the
brain and spinal cord, otherwise known as encephalomyelitis,
is either associated with this, subsequently follows, or comes completely
independent of these problems. A thickening of the footpads sometimes develops,
and vesicularpustular lesions on the abdomen usually develop. Neurological
signs typically are found in the animals with thickened footpads from the virus.About half of sufferers experience meningoencephalitis
Treatment
No antiviral drugs exist that effect canine
distemper virus
Treatments
are symptomatic and supportive, aimed at limiting secondary bacterial invasion,
supporting fluid balance, and controlling neurologic manifestations.
Broad-spectrum antibiotics, balanced electrolyte solutions, parenteral
nutrition, antipyretics, analgesics, and anticonvulsants are used, and good
nursing care is essential. No single treatment is specific or uniformly
successful.
Immunization
Excellent vaccines are now available to protect dogs
from canine distemper virus. These vaccines are manufactured from living,
weakened (attenuated) virus that induce long-lasting
immunity. Immunity lasts many years.
Vaccinations must not be given too early
to puppies. The shots must be given to puppies at a time when the level of
circulating antibody that they received from their mothers is in decline or the
vaccine’s effects are neutralized
Successful immunization of pups with canine
distemper modified live virus vaccines depends on the lack of
interference by maternal antibody. To overcome this barrier, pups are
vaccinated with the vaccine when 6 wk old and at 3- to 4-wk intervals until 16
wk old. Alternatively, measles virus vaccine induces immunity to canine
distemper virus in the presence of relatively greater levels of maternal
distemper antibody. MLV (modified live vaccines) measles vaccine is administered to pups 6–7 wk old and
is followed with at least two more doses of MLV distemper vaccine when 12–16 wk
old.
This
vaccine is usually administered through the 5-in-1 vaccine, or DHLP or DHPP
vaccines, at around six to 10 weeks, depending on the environment and exposure
to other animals.
*****
Sources:
http://en.wikipedia.org/wiki/Canine_distemper
http://www.petmd.com/dog/conditions/respiratory/c_dg_canine_distemper
http://www.2ndchance.info/dogdistemper.htm
No comments:
Post a Comment