The word "Parvo" strikes fear into the hearts of dog owners everywhere, and with good reason. Parvo is a deadly (but easily preventable) disease that usually strikes young, unvaccinated puppies and has a mortality rate with treatment of about 30-40% and upwards of 80% without treatment. Another viral disease, Ebola, has been in the headlines recently, and it's not too much of a stretch to say that Parvo is the Ebola of the puppy world. Many of the symptoms are the same, and the mode of transmission is the same for both diseases.
There is a cat parvovirus, just as there is a human parvovirus, but they are far different and cause different diseases than the canine version. Adding to the confusion, the feline parvovirus causes a disease called feline distemper, which is distinctly different from canine distemper, caused by yet another canine virus.
The following information on treatment, prevention, and the nature of the disease itself will help you better understand this condition, and hopefully help you and your dog avoid the potentially deadly misery of Parvo.
What Is Parvo?
Parvo is short for parvovirus, a very small virus that is transmitted from dog to dog through feces and vomit. The virus first appeared in the 1970s and is thought to be a mutation of the feline distemper virus. It caused widespread mortality because dogs had no immunity to the new virus and no vaccine was available for several years.
What Are the Symptoms of Parvovirus?
- Bloody diarrhea
- Loss of appetite
Dogs with this virus develop severe bloody diarrhea as the virus reproduces in the intestines, a disease known as parvoviral enteritis. Every episode of diarrhea sends more of the virus into the environment, quickly transmitting the infection to nearby puppies. It can spread like wildfire, quickly taking over a humane shelter or house full of puppies, and this mini-epidemic often ends with tragic results.
Vomiting, usually with blood, is also very common. Because of the fluid loss through vomiting and diarrhea, and because they can't keep any liquids down, dogs with Parvo rapidly become very dehydrated. The virus also attacks the bone marrow, so dogs can't mount a proper immune response to the virus, which compounds the problem. Weak, dehydrated, and debilitated, many puppies with Parvo succumb to organ failure or generalized infection due to the widespread, systemic damage.
How Is Parvovirus Diagnosed?
Diagnosis involves a specific test, known as an ELISA. It detects small quantities of the virus in feces and produces a color change if positive, similar to a home pregnancy test. While no test is 100% accurate, the Parvo test has few false positives and even fewer false negative test results. Most veterinarians carry the test, and results are available within minutes. The test costs around $30-80. Any vomiting puppy should be tested, regardless of the circumstances or vaccine history.
How Is Parvovirus Treated?
The best case scenario is to treat a Parvo puppy in a fully equipped hospital that has 24-hour care. Fluids maintain hydration in the face of vomiting, and antibiotics help prevent secondary bacterial infections while the immune system is under attack. Antibiotics do not affect viruses, but many dogs die of septicemia, which is a bacterial problem. There are several medications available to prevent and treat vomiting, and many of the Parvo puppies that I have treated need 3 or 4 of these medications to stop the vomiting and allow them to eat again.
Puppies in the hospital being treated for Parvo need to be in separate isolation wards from the general hospital population to avoid spreading the disease to other patients. Isolation is labor-intensive and expensive: staff treating Parvo puppies must don gowns, gloves, and booties every time they enter isolation to avoid spreading the virus on their clothes or hands. Many Parvo cases end up costing the owners $800 - $3,000, depending on the degree of severity and length of hospital stay.
In many cases, this level of intensive care is beyond the financial capacity of pet owners, who may have just adopted the puppy days before. At home care for Parvo, while possible, is not ideal. Fluids must be given under the skin subcutaneously rather than with an IV, and medications to control vomiting and infection are difficult to give at home. I have seen patients survive Parvo after being treated at home, but many do not.
For dogs that are unable to eat for more than 3 or 4 days due to the vomiting, some form of nutritional support is needed. It's a common misconception that IV fluids provide nutrition, when in reality they only provide water and a few electrolytes. IV nutrition is a costly and risky medical intervention that not every veterinary hospital can provide, so many Parvo puppies who do not quickly respond to therapy don't get adequate nutritional support, even in the hospital. They are starving while trying to fight off the virus. IV feedin,g known as parenteral nutrition, should be considered for any Parvo puppy who has not eaten in 3-4 days, but it can add $200-300 a day to the treatment costs.
How Can Parvovirus Be Prevented?
There is a ray of sunshine amidst all this gloom and doom, however. There is a readily available, inexpensive, and safe vaccine that gives vaccinated puppies a high degree of immunity to the virus. It's not a 100% guarantee that a vaccinated dog will not get the disease, but the chances are far, far slimmer with proper vaccination in puppyhood.
The vaccine is given staring at 4-8 weeks of age and repeated every 2-3 weeks until 4 months of age or until 6 months for at-risk breeds with a higher susceptibility to Parvo like Rottweilers, Doberman Pinschers, and Pit Bulls.
Puppies are at the most risk, and the risk tapers off with increasing age. I have never seen a dog over 4 or 5 years old with Parvo even with a lapsed vaccination history. Vaccines against Parvo are vital in the first few weeks of life, but vaccinating an older dog against it requires a risk-benefit discussion with your veterinarian.
What Should I Do with This Information?
While it's not a death sentence by any means, Parvo is a serious disease that requires aggressive care and a substantial financial commitment. It makes far more sense to vaccinate your puppy for $25 than to spend $2,000 on treating a preventable disease, with no guarantee of success. If your puppy isn't vaccinated, don't delay - make plans now to get the protection he needs. You might save your puppy's life, and you might also save yourself a whole lot of worry and money as well.
Do you work at a shelter, vet, or other puppy-filled place? The ASPCA has a handy webinar with advice on preventing a parvo outbreak.