Pet Parvo

Signs & Symptoms

Canine Parvovirus is one of the most dangerous illnesses that a dog can contract due to the virus’s rapid production and onset of symptoms.  That being said, it is important to understand how Parvo presents itself in dogs, and it is vital to become familiar with the signs and symptoms in order to recognize them in your own pet.  Both the intestinal and the cardiac forms of the disease have their own set of symptoms and present differently from one anothers dog.

What It Looks Like

The disease typically takes about 3-10 days after a dog is infected before he or she will start to show signs of Parvovirus. It is an acute illness, meaning that symptoms will show up very soon after exposure. If left untreated, the disease can cause death within a couple of days of the onset symptoms (Healthcommunities, 2007).  Below you will find a list of signs and symptoms for each form of the virus. Remember, diarrhea and vomiting do not always mean your dog has Parvo, so it is important to bring your dog to the veterinarian to confirm a diagnosis.

Cardiac & Intestinal Symptoms

The most devastating symptom of Cardiac Parvovirus is the sudden death that occurs in puppies, usually about 4 weeks old. The puppy may have cold arms and legs, may be gasping for air, or may even have convulsions.  Very sudden heart failure with respiratory complications typically occurs in puppies between 4 and 8 weeks of age. The puppies will have abnormally rapid breathing or shortness of breath, especially while exercising or running around.  The abdomen may also swell due to an enlarged liver. Most puppies will die due to cardiogenic shock, where the heart suddenly cannot pump enough blood to meet the body’s needs. If the puppy is lucky enough to survive, it will most likely suffer from chronic circulatory problems and issues with the muscles of the heart.  There is usually no diarrhea in this form because the virus multiplies in the heart and does not typically impact the intestines. In the heart, lesions may occur, and the lungs may produce a white and frothy liquid present in the trachea and bronchi (Nandi and Kumar, 2010).

Parvovirus itself does not directly cause death, but rather causes a loss of the lining in the intestines.  Damage may occur in the gastrointestinal tract and may impact parts of the small intestine, leaving it soft and limp.  The wounds often present in areas where there is rapid cell production, and the structures in the intestines used to absorb nutrients and fluids may collapse completely.  The loss of these structures can often lead to heavy diarrhea. The consistency and characteristics of a dog’s stool may not always be the same. Stool can vary from being watery, yellow, or even bloody. As a result of diarrhea and vomiting, rapid fluid loss is an immediate concern and can result in dehydration. If your dog is experiencing frequent diarrhea, it may be helpful to use dog diapers in order to keep your home clean.


If you notice any of the above symptoms, please take your dog to the veterinarian immediately. Canine Parvovirus is diagnosed based on the signs symptoms that are displayed, typically paired with laboratory testing to confirm the diagnosis. Your vet will first perform a routine physical check up and look at your dog’s comprehensive medical history. This will help him or her to have an understanding of the vaccines, treatments, and other medical related visits for your pet. It is important to remember that not all cases of bloody diarrhea and vomiting are caused by Parvovirus, but it is always recommended to get your pet checked, just to be safe.  Below are a few common tests performed:

Urine Analysis

A urine test may uncover electrolyte imbalances and could reveal any elevated liver enzymes.  The test also screens for a reduced number of lymphocytes (white blood cells), which fight off foreign matter and illnesses.  A reduced number of lymphocytes is an indicator that a dog does in fact have Canine Parvovirus.

White Blood Cell Count

A complete blood cell count will look at the number of white blood cells in a dog’s body, in addition to looking for Parvovirus antibodies.  A low count of white blood cells is a good indicator of the disease, as white blood cells are the body’s defense against foreign pathogens.  Parvovirus weakens the body’s ability to protect itself by destroying immune cells.

Abdominal X-Rays

An X-ray provides a picture of a dog’s body internally and may be performed in order to rule out other causes of gastrointestinal issues besides Parvo, such as an obstruction or foreign object in the intestines.  An abdominal ultrasound could also potentially reveal fluid build-up.


An ELISA test checks for the Parvo virus in a dog’s feces.  ELISA stands for enzyme-linked immunosorbent assay, one of the most common tests used to diagnose Parvo.  Parvo antibodies are placed into a testing chamber along with a stool sample. The antibodies attach to the virus if it is present in the feces, and a color-changing agent is added which will change color if the test is positive (Cornell University College of Veterinary Medicine, 2018).

  • A positive ELISA test in an animal presenting clinical symptoms is considered positive.
  • A negative ELISA test in an animal presenting clinical symptoms is still considered positive.
  • A positive ELISA test in addition to a low complete blood cell count is considered positive.
  • A negative ELISA test is considered negative for Parvovirus.

Electron Microscopy, Tissue Culture, and Viral Isolation

These are more advanced tests, however the financial cost of these tests are very hefty and many dog owners prefer to assume that the disease is Parvo, and would rather spend their money treating their sick dog rather than paying for tests to confirm the disease (Petwave).

Each of these evaluations listed above produce different information, so it is recommended to do a combination of all of these tests.  If it is determined that your dog does in fact have Parvo, he or she will most likely have a weakened immune system and will be much more susceptible to other diseases.  Ask your veterinarian how to protect your dog from getting sick and how to boost his or her immune system back up.

Top 5 FAQ

Dogs will typically start to show symptoms within 3-10 days after contracting the virus.

With proper care and treatment, a dog can typically recover in about a week.  However, he or she can still be contagious for up to 6 weeks as the dog’s body is still shedding the virus.

The first vaccine that your puppy will get will be at six weeks old, and then the next shot will be administered in two to four week intervals.  There are typically three shots total, and then a booster shot is administered one year later and then again every three years.  If you have an adult dog or a puppy older than 16 weeks, there are typically two vaccines administered three to four weeks apart.  Continued vaccination is recommended every three years.

Your dog has the best chance of being protected from the virus after he or she has had a complete round of vaccines.  Limit your dog’s exposure to areas where there are lots of dogs confined in small spaces, such as dog parks, pet stores, etc.

The virus does not always have a distinct smell, but it may cause a very foul-smelling diarrhea that is generally associated with blood and/or mucus in the feces.

Other Frequently Asked Questions

After treatment, a dog can continuously shed the virus for up to six weeks, however a dog may not still be showing any signs or symptoms of the disease during that time.


What Is Parvo?

Canine Parvovirus is a highly contagious disease that occurs in dogs. There are two forms of the disease: Cardiac Parvo and Intestinal Parvo.


There are several different methods used to treat Parvo in dogs. Learn about treatment methods at home vs treatment methods at the vet.


Learn about the different steps you can take to prevent your dog from contracting Canine Parvovirus.


A Guide to Finding Forever Homes for Animals with Disabilities

How To Find Forever Homes for Animals with Disabilities

As animal lovers and advocates, we believe that every animal …

Read More
Canine Separation Anxiety

Helping Your Pup Cope: Understanding and Managing Canine Separation Anxiety

As much as we love our furbaby, there will always …

Read More