What is Parvo?
Commonly known as parvo, this disease is caused by canine
parvovirus (CPV-2). Infection with parvovirus is most commonly seen in young,
unvaccinated puppies. The virus is very hardy in the environment and is
resistant to many common cleaners and disinfectants, under the right conditions
it can persist for years. Puppies become infected through oral or nasal contact
with fecal material or objects/surfaces contaminated by the virus. Parvovirus
is highly contagious to other dogs, after they become infected, and often
before they start showing any signs of illness, they start to shed the virus in
their feces. This viral shedding continues even past the point of recovery and
other dogs in the area are at serious risk. The good news…parvo is preventable!
What does Parvo do?
Once canine parvovirus enters the body through contact with
fecal material containing the virus or fomites (objects, people, surfaces,
etc.) contaminated by the virus, it begins to replicate and spread throughout
the body. The virus has preferences for certain tissues in the body to infect,
including the small intestine, the bone marrow, and lymph tissue. The virus
infects and destroys cells in these tissues causing the clinical signs that we
commonly see. Because the small intestine is affected we see vomiting and
bloody diarrhea, along with non-specific signs of illness like lethargy,
anorexia, and fever. In a puppy these signs can rapidly progress to dehydration,
collapse, shock, and ultimately death.
Diagnosis
Parvovirus can be diagnosed with a quick ELISA test that
most veterinarians have in hospital, used on a sample of fecal material. This
test is very accurate but a false negative is possible if it is early in the
disease before high viral shedding. Routine bloodwork can also help with a
diagnosis as infected dogs often have very low numbers of white blood cells due
to the virus destroying the bone marrow.
Treatment
Parvovirus is treated with supportive care until the dog’s
immune system can fight off the virus. Aggressive treatment must be started as
soon as possible if parvo is suspected. Treatment includes fluid therapy,
anti-nausea medications, antibiotics to prevent secondary bacterial infection,
and nutritional support. There are potential complications of parvovirus that
may require surgical intervention.
Most deaths occur within 24-48 hours after clinical signs
appear. The risk of rapid death, severe complications, and the cost of
intensive hospitalization demonstrate why prevention of this disease is so
important.
Prevention
Parvovirus is largely preventable with vaccination! Parvovirus
vaccines should be administered to puppies at approximately 8 weeks old, 12
weeks old, and then 16 weeks old. They should get another vaccine at 1 year of
age and then they can be vaccinated every 3 years. Adult dogs should be kept
current on their parvo vaccinations to prevent any risk of infection.
Reducing exposure to the virus is also an important
consideration. Puppies should not be taken to parks, pet stores, puppy classes,
etc. before they are fully vaccinated. Prompt removal of fecal waste can help
prevent the spread of parvovirus, and areas where infected puppies have been
should be properly disinfected.
Contagion
Canine parvovirus is highly contagious. Sick puppies should
be isolated from other dogs as soon as infection is suspected. Please alert
your veterinarian to the signs that you are seeing before you bring your puppy
into the waiting room so they can take precautions to protect the other
patients. Puppies diagnosed with CPV are hospitalized in an isolation ward to
protect them and other pets in the hospital. CPV is not contagious to humans.
Learn more about
Shilo Gardner, DVM
