Can a Dog Catch Parvo Virus If They Have the First Shot?

Limit your puppy's outdoor exposure until he receives all vaccinations.
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Parvovirus is one of the cruelest of all canine diseases. First, it knocks out a dog's immune response, then targets the lining of the intestines, destroying his capacity to absorb nutrients from food. With the intestines so badly damaged, fecal bacteria then seep into the bloodstream, poisoning the dog. Puppies are certainly vulnerable to contracting parvovirus after they've had only their first vaccinations, but taking a few precautions can greatly reduce the risk. Adolescent and adult dogs who haven't had their shots as puppies should also be immunized.

Vaccination and Other Precautions

The standard course of vaccines immunizes dogs against five diseases, canine parvovirus, or CPV, among them. Usually, the first shot is given to puppies ages 6 to 8 weeks, with booster shots at four-week intervals until they're 16 to 20 weeks old, according to the ASPCA website. Until then, your pup will remain susceptible to CPV, which he can contract outdoors from exposure to the feces of infected dogs. You can also inadvertently bring CPV indoors on the soles of your shoes and track it onto your floors and carpets, where it survives well too. Until your dog has achieved full immunity, it's a good idea limit outdoor exposure and avoid potential hotspots like dog parks, pet stores, doggie day care and kennels. If you have concerns about indoor contamination, one part bleach mixed with 30 parts water kills the virus, says the Baker Institute for Animal Health.

A Speedy Decline from Bad to Grave

Three to seven days may lapse between the dog's exposure to parvovirus and the onset of symptoms. General lethargy and loss of appetite is quickly followed by high fever, severe vomiting and bloody diarrhea. When that happens, the pup is at imminent risk of either dying from shock and dehydration or the toxic effects of the intestinal bacteria circulating through his bloodstream. Proceed to the vet's office at warp speed. She'll test a stool sample for parvovirus and possibly also the puppy's white blood cell count. If the diagnosis is parvovirus, she'll start aggressive treatment immediately to save the dog's life.

Recommended Course of Treatment

Without treatment, parvo dogs almost never pull through. Ideally, your sick puppy will be admitted as an in-patient to the vet's clinic, where he'll be put on an intravenous drip to replace the fluids he's lost from vomiting and diarrhea. He'll get antibiotics, either by injection or by being added to the IV bag, to combat the effects of the fecal bacteria in his bloodstream. To help stop the pup from losing any more fluids from vomiting, your vet might also add anti-nausea medication to the drip. From then on, your puppy's condition will be carefully and constantly monitored. The good news is that he now has an excellent chance of making a full recovery. The bad news is the cost, which typically ranges between $1,500 and $3,000, putting it out of reach for many people.

A More Affordable Alternative: Home Care

In 2013, Zoetis Animal Health funded a study, conducted by the College of Veterinary Medicine and Biomedical Services at Colorado State University, into the efficacy of treating parvo dogs at home using two recently released drugs. Among dogs treated as veterinary in-patients, the CSU reported a survival rate of 90 percent, but the survival rate for dogs receiving intensive care at home using the new drugs wasn't much lower -- 80 to 85 percent. When a dog is that sick, home care requires a tremendous amount of work, CSU warns, but for owners who are up to it, the cost ranges only from $200 to $300. The researchers hope that every year, this protocol will save the lives of thousands of dogs owned by people who can't afford in-patient care. The CSU's Center for Companion Animal Studies has published free and highly detailed instructions for vets willing to help their clients treat parvo dogs at home.