The Physical Illness and its Treatment
Treatment for parvoviral infection centers on supportive care. This means that the clinical problems that come up in the course of the infection are addressed individually with the goal of keeping the patient alive long enough for an immune response to generate. We do not have effective antiviral drugs and must rely on the patient’s immune system for cure.
BE PREPARED FOR A 5-7 DAY HOSPITAL STAY AND A SUBSTANTIAL EXPENSE.
There are certain basic treatment principles which can be viewed as “must haves” in addressing the parvo puppy
Beyond these basics are some “added pluses” which may or may not contribute to the chance for survival. In order to achieve the usual survival rate of approximately 75-80%, the basics must be delivered. If an owner is less concerned about expense and simply wants to maximize survival chances, some of the optional treatments may be employed.
ANTIBIOTICS: The second way parvo kills is through bacterial invasion of the circulatory system (“sepsis.”) The intestine is normally full of bacteria and when the parvovirus ulcerates the intestine there is little to prevent the bacteria from marching easily into the bloodstream. With the GI tract damaged, antibiotics cannot be given orally. They are given either as shots or are added into the IV fluid bag. There are a number of antibiotics which may be selected. Some antibiotics you may see in use include:
Our hospital tends to prefer intravenous cefazolin in combination with intravenous metronidazole as a basic choice. For more information on cefazolin you may wish to read the Pharmacy Center section on its sister drug: Cephalexin.
Recently, Zoetis, formerly Pfizer Animal Health, has released cefovecin, a single injection of which lasts 2 weeks. This product has not been adequately tested in puppies under age 16 weeks but may find a place in the treatment of older puppies.
CONTROL OF NAUSEA: Patient comfort is a very important part of treatment for any disease but is especially important for parvo treatment as these puppies feel extremely nauseated. Again, the GI tract is too damaged for oral medication so medications are given as injections. There are several popular medications for nausea control:
The vomiting typical of parvo infection is not only uncomfortable but can ulcerate the esophagus. The disease itself ulcerates the stomach and small intestine. Medications called “gastroprotectants” help heal ulcers and help minimize their formation. These medications include the injectable antacids (cimetidine, ranitidine, or famotidine) as well as sucralfate, which forms webbing over ulcers to facilitate healing.
EXTRA TREATMENT WHICH MAY HELP:
Abnormal motility of the intestines occurs with this infection. Sometimes an area of intestine actually “telescopes” inside an adjacent area in a process called “intussusception.” This is a disastrous occurrence as intussusception can only be treated surgically and parvo puppies are in no shape for surgery. Euthanasia is usually elected in this event.
Total blood protein
Protein depletion is common when there is heavy diarrhea. If blood proteins drop too low, special IV fluids or even plasma transfusions are needed to prevent massive life-threatening edema.
Plasma is the protein-rich fluid that remains when the red blood cells are removed from a sample of blood. These proteins may include antibodies against the parvovirus, albumin to help expand the patient’s blood volume, as well as other healing proteins. Plasma can be obtained from donor dogs in the hospital or can be purchased from animal blood banks.
CEFOXITIN (A SPECIAL ANTIBIOTIC)
The best antibiotic coverage controls both gram negative and gram positive organisms, both aerobic and anaerobic organisms and does so with minimal side effects. The use of Cefoxitin (brand name Mefoxitin®) does an excellent job of covering for the organisms of concern without the kidney side effects of gentamicin or amikacin and without the cartilage side effects of Baytril.
This product represents anti-serum (antibodies extracted from horses) which binds the toxins of any invading GI tract bacteria. The use of this product is controversial though the veterinary teaching hospital at Auburn University uses it commonly. It is usually given only one time as the equine origin of the product has potential for serious immunological reactions.
There have been many studies indicating the benefits of single doses of these medications in the prevention of septic shock. Repeated doses may cause further GI ulceration (which is obviously something a parvo puppy has enough of). The usual medication is flunixin meglumine (banamine®).
“Neupogen” is the brand name of a genetically engineered hormone called “granulocyte colony stimulating factor.” This hormone is responsible for stimulating the bone marrow to produce white blood cells and its administration easily overcomes the bone marrow suppression caused by the parvovirus. In other words, neupogen helps the white cell count recover. A recent study did not find increased survival with the addition of this product to the parvo regimen; however, in sicker puppies it may make a significant difference. It is very expensive usually adding $100-$200 to the basic treatment cost.
HOME TREATMENT FOR PARVO
Home treatment for parvo infection is a bad idea when compared to hospitalization and intensive care. Mortality rises substantially and the heavy diarrhea and vomiting lead to heavy viral contamination in the home. Still, if financial concerns preclude hospitalization, home care may be the puppy’s only chance. Fluids will have to be given under the skin at home as will injectable medicines.
Page last updated: 1/31/2015