What to know about canine parvovirus, deadly virus that targets puppies

Long Island pet owners are being urged to vaccinate their puppies, after New York City reported a mid-March spike in parvovirus, which can be deadly for young dogs.

“Parvo is the one that’ll most likely affect your puppy severely and kill it — and even if your puppy survives, you end up with a very big bill for veterinary treatment. It can be thousands of dollars,” said Colin Parrish, a professor at Cornell University College of Veterinary Medicine’s Baker Institute for Animal Health.

State Department of Agriculture and Markets veterinarians were not aware of any parvovirus cases on Long Island, but local veterinarians fear the virus could spread to the suburbs. The Northeast pipeline of rescues from Southern shelters heightens this threat, as puppies may not have had all their shots — or only look healthy.

Here’s what you need to know about parvovirus:

How bad was the NYC outbreak?

On March 15, the Animal Care Centers of New York City shelter said several cases of parvovirus were detected in a 24-hour period.

Six days later, the nonprofit reported 14 dogs with the virus, mainly in the Bronx and Manhattan, according to the city’s Department of Health and Mental Hygiene commissioner, Dr. Ashwin Vasan.

“This far exceeds what is typically seen over the course of a single year,” he said, adding other hospitals were seeing more cases, too.

City officials did not provide an update on any new cases.

What are the symptoms of parvovirus?

Parvovirus, which spreads by contact with animal feces, affects dogs’ gastrointestinal tracts and bone marrow, according to Dr. Diane Levitan, associate professor at Long Island University’s College of Veterinary Medicine.

Fatality rates can hit 90%, and puppies and even unvaccinated adults may die within a few days of suffering from fatigue, loss of appetite, pain, fever, diarrhea, and vomiting.

Sepsis, which occurs when infection sends the immune system haywire and can cause organ failure, shock and death, is also a risk.

“Treatment is largely supportive care to help the animal's body fight the infection,” said Dr. Michelle E. Matusicky, an assistant professor at The Ohio State University College of Veterinary Medicine. Fluids, electrolytes, gastrointestinal-calming drugs and even feeding tubes may be needed.

Ailing pets also must be quarantined.

Some breeds prone to this illness, Levitan said, are Doberman pinschers, rottweilers, American pit bull terriers, English springer spaniels, and German shepherds.

Wolves, coyotes, raccoons, minks, foxes and bobcats also can catch parvovirus, and cats can be infected with a similar virus, panleukopenia.

Mating season is likely one of the more dangerous times for the virus, which, according to Cornell University, “can be seen year-round, but since parvovirus infections are more common in juveniles, disease will likely be observed more in the late spring or early summer months due to seasonality of breeding.”

How do out-of-state-adoptions affect the spread of the virus?

The spread of the virus between states and cities is not uncommon, said Dr. Carly Fox, senior veterinarian in emergency medicine at New York City’s Schwarzman Animal Medical Center.

New York requires veterinarians to attest that out-of-state rescues are healthy, but, said Fox, “On average, clinical signs do not start until day 5 to 7 after exposure. So a seemingly ‘healthy’ puppy can cross state lines but be actively shedding the disease.”

Last year, about 9,000 dogs came to New York State. The Centers for Disease Control and Prevention said the United States imports about 1 million dogs every year.

The American Veterinary Medical Association is calling for passage of a congressional bill that would ban importing dogs younger than six months and requiring veterinarians to confirm their health.  

How can parvovirus be prevented?

Vaccines are key to protect puppies from the virus, veterinarians said.

Puppies should get “at least three doses of a combination vaccine between 6 and 16 weeks, 2-4 weeks apart,” the American Animal Hospital Association said. And then, the association said, dogs should receive “two doses of a combination vaccine, 2-4 weeks apart,” along with boosters after a year and then at three-year intervals.

These vaccines also block possibly lethal distemper and canine influenza.

Always take a newly adopted dog to a veterinarian before bringing it home, Nassau County SPCA board president Gary Rogers said.

“Maybe the vet can spot something early, treat it and catch it — and you don’t go through the traumatic experience” of losing a puppy or infecting other pets, Rogers said.

Parvovirus, which thrives in dark and moist places, can linger on just about anything — from bedding to grass — so disinfecting needs to be rigorous.

Workers caring for the stricken should not tend to healthy dogs, if possible, as the virus can spread from their hands, clothing or shoes.

Any waste must be scrubbed off before applying special disinfectants, such as “accelerated hydrogen peroxide, potassium peroxymonosulfate, sodium hypochlorite” or bleach, the American Veterinary Medical Association said.

Lawns can be hosed — provided they dry swiftly — to dilute any virus present. Cement exercise yards also can be cleansed.

But Matusicky warned against using high-pressure hoses that can “aerosolize” the virus.

Fox said dogs that are not fully vaccinated should avoid travel.

Dr. Lori Teller, president of the American Veterinary Medical Association, agreed.

“I think the best thing to be done is to ensure the health of the puppies before they are transported. It’s pretty stressful to transport sick puppies — that really doesn’t help them recover faster,” she said.