Parvovirus – An update

By Beth Davidow, DVM DACVECC

ACCES Medical Director

A week ago, we alerted referring veterinarians in the area to an uptick in the number of parvovirus cases we were seeing at ACCES’ two referral hospitals (Seattle and Renton). Word quickly spread to the greater community setting off an unexpected scare.

Parvovirus is a virus that causes vomiting and severe diarrhea. In addition, it can suppress the immune system and put animals at risk for secondary infections. It mainly affects puppies and can cause death if not treated appropriately. With treatment, which includes intravenous fluids, anti-nausea medication, antibiotics and plasma in severe cases, survival is 90%. Adults dogs can get the infection as well but often are less sick or may shed virus and not have clinical signs.

The virus is shed in stool and can live in the environment for weeks to months. It is extremely hardy and not killed by standard disinfectants – bleach is most effective. The virus can be passed from an animal shedding the virus, picked up on clothes, shoes, and other objects, and then carried to another animal.

Parvovirus is not a new infection. It is a virus we have known about for a long time and one of the first diseases for which we developed a vaccine for dogs. The vaccine is extremely effective when administered properly. Puppies need to receive vaccines every three to four weeks from eight weeks of age until they are over 16 weeks of age, again at one year and then every three years thereafter.

The difficulty with this disease is that puppies often get sick in the window after they have had one vaccine but not the full series. If puppies are in environments where the virus has been shed by asymptomatic carriers, they can pick up the virus. Health for the dog population relies on compliance by everyone – a concept known as “herd immunity”.

This year we have seen an uptick in the number of parvo cases. We see an average of 16 cases a year and have diagnosed 28 this year, eight in the last three weeks. The virus does ebb and flow so this may just be a high year. Cases have been from a number of locations and have been mostly young, incompletely vaccinated dogs. However, it is also possible that the move away from vaccines has led to less herd immunity and more shedding of virus. Speaking to other hospitals in the area, some are also seeing more cases but other clinics north of us are not.

Our recommendations are:

1)     VACCINATE – make sure your puppy gets the full SERIES of vaccines up to at least 16 weeks of year. Make sure the vaccine is boostered one year later and then every three years after that.

2)     Do not take incompletely vaccinated puppies to dog parks or other high traffic areas. Dog parks are great places to socialize but only after the full series of puppy shots have been given.

3)     If you have a dog with vomiting and diarrhea, have them seen promptly. Early diagnosis and proper treatment does lead to a good long term outcome.

If your dog is fully vaccinated, there is no reason to avoid the dog parks – let your dogs play if we have a sunny day. 

Meet the Tripods!

By Beth Guerra, DVM

A while back, I wrote a blog about my three-legged poodle, Matilda. She was brought into ACCES Seattle during my first month of work, around the time I was looking to add a second dog to my household. She had sustained severe injuries to both the skin and bone on her right forelimb, and after consulting with our surgeon about several possible options, I chose amputation of the limb. She was estimated to be six months old at the time, and in the four years since then has flourished. She navigates stairs with ease, jumps on and off the bed more easily than my quadruped dog, and frequently runs 5Ks with me. I don’t think she remembers ever having four legs.

Matilda

This past fall, we added a second tripod to our home. Fiona is a long haired Chihuahua mix that was brought in by the King County Animal Control after she was found as a limping stray. The x-rays showed a fractured left elbow, and the decision was made to amputate the limb. She was about three months old at the time. I came back after some time off to discover her still convalescing in the ICU, and I fell in love with her immediately. Like Matilda, she was up and walking the day after surgery, and hasn’t looked back since. While her stature, combined with a missing leg, does make it hard for her to jump off furniture and climb stairs, she is extremely active, runs at the dog park, and grapples with our other two dogs.

Fiona

I have learned that each of my tripods has adapted to life differently. Each has a unique gait, which I did not expect. Matilda can move at slow speeds and stay balanced, but Fiona is constantly running to her destination and occasionally face-plants. Each dog chooses to present herself differently to new people. Matilda will bat you with her oversized front paw, but Fiona tends to hang back and hide. Each dog is a novelty at the dog park, and stimulates many conversations that revolve around rescuing pets and limb amputations. Although my dogs are small, and small dogs generally adapt better after losing a forelimb, I always tell people that this type of amputation does not necessarily mean a huge change in the quality of life for their pet, especially if it is a large breed dog. As they run full out at the park, my dogs are an ambassador for those pets with disabilities, proof that every dog deserves a chance, and that spirit can overcome a handicap.

For more information on three legged dogs, visit www.tripawds.com

When Repeating Diagnostics Makes Sense

By Beth Davidow, DVM DACVECC 

Many times clients will ask why we are repeating a test.  It does seem that if you have just had blood work done recently, things shouldn’t be that different.  However, when an animal is sick, things can change dramatically over a period of hours.  The following case is a good example.

A seven and a half-year-old pointer was referred to our ICU for care of a suspected reaction to a chemotherapy drug.  A review of his case showed that the dog had a skin lump that turned out to be an atypical form of a cancer called lymphoma.  (Lymphoma is a cancer of lymph nodes and lymphatics and doesn’t usually show up as a skin nodule.)  Initial screening showed no evidence of the cancer anywhere else.  The dog had been given a chemotherapy drug three weeks prior to presentation.  The tumor shrank dramatically in size and he seemed to feel well.  Many chemotherapy drugs can suppress the body’s infection fighting cells, the white blood cells, and this did happen seven days after the drug was given.  The dog was put on antibiotics and seemed to be fine.  However, three weeks after the drug was given, the dog acutely started having vomiting, diarrhea and was severely weak.  He had a fever and a borderline low white blood cell count.  Bloodwork, radiographs and ultrasound were done and no evidence was seen of any new cancer.  It was assumed that he had an infection secondary to having the low white blood cell count.

When the dog arrived at ACCES, he was dehydrated, weak and had a fever.  He had been started on IV fluids, antibiotics and anti-nausea medications at the regular veterinarian and those treatments were continued.  However, at 10:00 pm he was still febrile and now couldn’t stand up.  A blood glucose (blood sugar) was rechecked and had fallen to a dangerously low level. He was given IV glucose and was much brighter.

Why did the blood glucose fall in only 12 hours?  Normally dogs can maintain their blood sugar in a normal range even if they aren’t eating.  In the face of overwhelming infection, sometimes the bacteria are “stealing” the glucose and blood values will fall quickly.  Sometimes, if the body’s normal stress mechanisms aren’t working, it can also fall.  Sometimes, tumors can also “steal’ glucose but we hadn’t found any new cancer.  Our working hypothesis was that we still weren’t on top of the infection.  We started an additional antibiotic.

Over the next 24 hours, the glucose stayed normal and the fever resolved but the dog was still very depressed and wouldn’t eat.  The next morning, 48 hours after the initial illness started, small pinpoint bruises were noted on the skin.  This can be a sign that the clotting system isn’t working.  We checked the clotting blood values and found that the platelets, small particles in the blood that make the initial clot, were now very low, even though they had been OK the day before.  A full complete blood count was sent to the lab.  A falling platelet count can also be a sign of infection or emerging cancer but the fever was under control.  What was happening?

In the afternoon, we had our answer.  The complete blood count, which had only normal blood cells 48 hours before, now showed cancer cells in the blood.  The cancer, despite being gone from the skin, had lodged in the bone marrow and in a 48 hour period and multiplied fast enough to be found in the blood stream.  The dropping glucose and platelets were not from a chemotherapy reaction or from infection but from the emerging cancer we couldn’t yet see.

Thus, repeating the same tests several times allowed us to diagnose the reemerging cancer quickly.  It was a lesson of how rapidly things can change in the body.