Canine parvovirus (CPV or commonly referred to as “parvo”) is one of the most serious viruses that dogs can get. Thankfully, it is very preventable with proper vaccination.
This virus was discovered in 1967 and has rapidly become a serious threat to canine health. This is primarily due to the fact that the virus is hard to kill, can live for a long time in the environment, and is shed in large quantities by infected dogs.
The virus is also highly contagious, which is why the parvo vaccine is considered a core vaccine for puppies and dogs.
While the highly effective parvovirus vaccine has decreased the risk to properly vaccinated dogs, this disease is unfortunately still widely prevalent, especially in puppies and adolescent dogs.
Here’s everything you need to know about parvo in dogs—how to protect your dog from it, the signs of parvo that you should look for, and what to do if you your dog is showing symptoms.
Jump to a section here:
- What Is Parvo in Dogs and Puppies?
- How Do Dogs and Puppies Get Parvo?
- What Are the Stages of Parvo?
- What Are the Signs of Parvo?
- How Long Does Parvo Last? What’s the Prognosis for Parvo Cases?
- How Is Parvo Diagnosed?
- How to Treat Parvovirus
- How to Prevent Parvo
- Can a Vaccinated Dog Get Parvo?
- Can a Dog Get Parvo Twice?
Parvo is an infectious DNA virus that commonly causes severe illness in young and unvaccinated dogs.
It primarily affects the rapidly dividing cells of the body, meaning that the intestinal tract and bone marrow are the worst affected.
Although parvovirus is most common in puppies and adolescent dogs, it can affect adult or senior dogs, especially if they are unvaccinated.
Parvovirus is an incredibly contagious disease that spreads quickly and efficiently. So how exactly does it spread?
While canine parvovirus is not airborne, it can be found on many surfaces within the environment.
It is spread by contact with contaminated feces, but you don’t have to see solid feces for the virus to be present. It can live on the ground or on surfaces in kennels, on peoples’ hands, or on the clothing of people that have been contaminated. Dogs could also carry it on their fur or paws if they have come into contact with contaminated fecal material.
Parvovirus can live outdoors for months, if not years, and is resistant to many disinfectants, although it is susceptible to diluted bleach and some specialized cleaners commonly used in veterinary hospitals.
Parvovirus is species-specific, so humans have their own version of the virus. This means that humans cannot get parvovirus from dogs, and dogs cannot get parvovirus from people.
However, it’s still important to use the utmost caution by wearing personal protective equipment if you come into contact with an infected dog. While you may not get parvo, the virus could be spread to another dog via your hands or the clothes you are wearing.
Cats also have a type of parvovirus that causes severe disease, known as feline panleukopenia.
While dogs cannot get feline parvovirus from cats, cats can become infected with canine parvovirus. They most often have much more mild clinical signs than dogs do, but there is a strain of canine parvovirus that can cause severe illness in cats.
The feline parvovirus vaccine, which is part of the core FVRCP vaccine, may offer some cross-protection against canine parvovirus.
A dog infected with canine parvovirus will start to show symptoms within three to seven days of infection.
An infected puppy will often show lethargy as the first sign, and they may not want to eat. They will also often have a fever.
As the virus progresses, your dog will begin to suffer from severe vomiting and diarrhea.
Fecal ELISA tests (enzyme-linked immunosorbent assay) are the most common way of diagnosing a dog with parvovirus in a clinical setting.
The test requires a fecal swab and takes about 10 minutes.
While this test is accurate, a negative result does not necessarily rule out parvovirus in a symptomatic dog, as they may not be shedding the viral antigen at the time of testing. Further testing may be needed in these cases.
The stages of canine parvovirus follow the stages of most viral infections.
The puppy (or adult dog) is exposed to viral particles via fecal material from an infected dog. These viral particles can come from a few places:
- The environment, on the ground or on a surface
- The mother dog
- People/clothing/inanimate objects that came into contact with the feces of an infected dog
Only a very small amount of fecal material is necessary to cause infection, which enters through the mouth of the puppy or dog.
There is an incubation period (between three and seven days) in which the dog is infected with parvovirus but not yet showing symptoms.
During this period, the virus specifically seeks out the most rapidly dividing cells in the body—typically, it starts attacking the tonsils or lymph nodes of the throat. By targeting these rapidly dividing cells, the virus is able to multiply effectively and efficiently and invade other parts of the dog’s system.
Once it has multiplied and entered the bloodstream, the virus will seek out other sources of rapidly diving cells. The most hard-hit areas are:
- Bone marrow
- Cells that line the walls of the small intestines
In small puppies, parvovirus can also infect the heart, which causes inflammation of the heart muscle, poor heart function, and arrythmias.
When the virus infects the bone marrow, it attacks the young immune cells, which leads a drop in protective white blood cells.
This weakens the body’s ability to protect itself and allows the virus to more easily invade the gastrointestinal (GI) tract. This is where the worst damage happens. The virus attacks the lining of the small intestine, which prevents the dog’s GI tract from being able to:
- Absorb nutrients
- Prevent fluid loss into the stool
- Prevent bacteria from moving into the gut
This leads to serious health issues, such as:
- Severe dehydration
- Possibly sepsis
While parvo in dogs is not always fatal, those that do not survive typically die from dehydration or shock—along with the damage caused by the septic toxins from the intestinal bacteria escaping into the bloodstream.
Recovery from parvovirus varies case by case. Full recovery may take quite a while depending on the severity of the disease and the damage it has done.
Dogs that can recover from infection are sick for five to 10 days after symptoms begin.
It is very important that puppies with parvovirus receive adequate nutrition so that their intestines can heal.
Dogs recovering from a parvo infection should be fed a bland, easily digestible diet. Hill’s, Purina, and Royal Canin all make prescription veterinary diets that are carefully formulated to be nutritionally balanced and gentle on the GI tract:
- Hill’s Prescription Diet Digestive Care i/d dry dog food
- Hill’s Prescription Diet Digestive Care i/d wet dog food
- Purina Pro Plan Veterinary Diets EN Gastroenteric dry dog food
- Purina Pro Plan Veterinary Diets EN Gastroenteric wet dog food
- Royal Canin Veterinary Diet Gastrointestinal Low Fat dry dog food
- Royal Canin Veterinary Diet Gastrointestinal Low Fat wet dog food
Hospital stays generally last around five to seven days, but this varies depending on the severity of symptoms.
The highest risk of death occurs around 24-72 hours after you see the symptoms of parvo in dogs.
If a puppy is hospitalized, given lots of supportive care, and monitored closely, the survival rate is around 75-80%. Survival is more difficult if the dog is not given veterinary attention quickly after showing clinical signs, or if the dog is not hospitalized with sufficient supportive care.
There are no home remedies for parvo.
In some cases, if a dog is not severely ill, or if expensive treatment is prohibitive, then treatment on an outpatient basis may be attempted with help from the vet.
Outpatient treatment for parvo in dogs includes:
- Subcutaneous fluids (fluids given under the skin as a source of hydration)
- A special highly digestible diet
- Antiemetics to stop vomiting
- Possibly antidiarrheals
While some dogs can recover from this protocol, it is much safer—and more likely to have better outcomes—if the dog is hospitalized.
There is no cure for parvovirus, so the treatment revolves around supporting the puppy so their body can fight off the virus.
Supportive care for parvovirus generally includes:
- Hospitalization with intravenous fluids
- Antiemetics to stop vomiting
- Focusing on nutrition, with a feeding tube, if necessary
- Correction of any electrolyte imbalances or low blood glucose
Puppies exhibiting signs of sepsis—where the gut becomes so “leaky” from disease that bacteria from the intestines enter the bloodstream—require antibiotic therapy.
Puppies with a high fever or low white blood cell count may also receive antibiotics.
How Much Does Parvo Treatment Cost?
The cost of treatment can vary greatly based on the severity of illness, length of hospital stay, and location of the veterinary clinic.
Costs could start around several hundred dollars for outpatient treatment and up to several thousand dollars for a severe case with hospitalization.
On average, expect treatment to cost $1,000-1,500 minimum.
Needless to say, it is much more cost-effective to have your dog fully vaccinated than to have a dog with parvovirus.
The canine parvovirus vaccine is most often given in a combination vaccine that goes by a variety of acronyms: DHPP, DAPP, DA2PP, DHLPP, etc. This vaccine is considered a core vaccine and should be given every three to four weeks from 6 weeks to at least 16 weeks of age.
The most important thing is making sure you get your puppy in on time for their vaccines. If too much time has passed between boosters, the vaccine series will need to be started over again to maintain protection.
Puppies should only socialize with fully vaccinated dogs until they are able to be fully vaccinated. Areas where vaccination status is not ensured, such as dog parks, should be avoided.
An exception is puppy classes at a reputable training center, as all puppies are required to have at least their first vaccine against parvovirus, and training and socialization at an early age are extremely important.
A dog will need to receive a booster vaccine at one year of age to be considered fully vaccinated. Dogs should also continue to receive vaccines every one to three years for life.
While no vaccine can promise to be 100% effective, the canine parvovirus vaccine is very effective and provides excellent protection from the virus. It is very unlikely that an appropriately vaccinated dog would become ill with canine parvovirus.
It’s important to make sure that puppies get the appropriate number of boosters based on their age, and that they are then boostered after one year, and then every one to three years.
If a vaccinated dog comes into contact with a dog that is sick and actively shedding parvovirus, it would not be unreasonable to booster the vaccine early.
While not impossible, it is very unlikely that a dog that has recovered from canine parvovirus would get it again.
Immunity for parvovirus lasts for several years.
However, this does not mean that your dog does not need to be vaccinated against canine parvovirus if he or she has recovered from it in the past. Routine vaccinations should still be performed.