Parvo enteritis, Part 2

In the last column I went over some the basics of canine parvo enteritis.  We were getting to contamination of environment.  A contaminated an environment is usually from infected dogs shedding the virus in stool.  This is in humongous numbers during the two weeks following exposure.  There is a HUGE potential for environmental contamination when an infected dog has been in a location. 
A typical infectious dose for an unvaccinated dog is 1,000 viral particles.  A dogs  immune status against parvo will change the amount There are some dogs that need far less,  other dogs  a larger number of infective virus units are needed.  The phrase your mileage may vary is a take off on this exception statement.  An infected dog sheds 35 million viral particles (35,000 times the typical infectious dose) per OUNCE of stool.
A Parvoviral infection is easier to pick up an infection from an area where an infected dog has been.  This is simply because of the larger number of virus units in a contaminated area.  Whether an individual dog gets infected or not depends on the number of viral particles the dog experiences, what kind of immune experience the dog has had with the virus before (vaccinated? previously infected? how much past exposure?), and how strong the individual dog is (stress factors, diet, etc.).
Indoors, the virus usually loses its infectivity within one month.  It should be safe to introduce a vaccinated new puppy indoors one month after the active infection has ended. 
Outdoor decontamination: Freezing is completely protective to the virus.  If the outdoors is contaminated and is frozen, one must wait for it to thaw out before safely introducing a new puppy.  Consider shaded areas contaminated for 7 months.  Areas with good sunlight exposure, ultraviolet light, are considered contaminated for 5 months.   Of course, that is without proactive decontamination steps being taken. 
How do you disinfect a house to create a safer environment for other household dogs? How can I create a safe environment for a new or replacement puppy?
Disinfection: Despite the introduction of new cleaners with all sorts of label claims, parvovirus is virtually impossible to be completely remove from an environment.  The decontamination goal is to reduce the number of viral particles to an acceptable level.  The best and most effective disinfectant against viruses (including parvoviruses) is BLEACH.  One part bleach is mixed with 30 parts water and is applied to bowls, floors, surfaces, toys, bedding, and anything contaminated that is colorfast or for which color changes are not important.   Add 1 ounce of bleach to 1 quart of water.   This bleach mixture completely kills parvovirus.
Disinfection is a problem for non-bleachable surfaces such as carpet or lawn.  Outdoors, if good drainage is available, a thorough watering down of the area may dilute any virus present.  Since carpet is indoors, it may best to simply wait a good month or so for the virus to die off before allowing puppies access to the area. 
Treatment for Parvoviral infection focuses on supportive care.  The clinical problems, which come up during the course of the infection, are addressed individually.  The goal is keeping the patient alive long enough to generate an immune response.  We do not have effective antiviral drugs.  Veterinarians rely on the patient's immune system for a cure. 
Isolation from other animals is paramount in treatment.  Parvo puppies have an overwhelming suppression of white blood cells.  They are in one sense are like the boy in the bubble or bone marrow transplant patients.  The next bug introduced may be terminal.   There needs to be 7-14 days of intensive care given.  IV medications will include fluids, antiemetics, antibiotics, vitamin B complex, and nutritional care.  This may include   placement of an esophageal or gastric PEG tube in severe cases. 
Vomiting typical of parvo infection is uncomfortable and can ulcerate the esophagus.  The disease ulcerates the stomach and small intestine.  Gastroprotectants help heal ulcers and help minimize their formation.  These are the injectable antacids (cimetidine, ranitidine or famotidine) and sucralfate, which forms webbing over ulcers to facilitate healing. 
IV Fluid therapy is needed to offset parvovirus metabolic derangements occurring with dehydration.  We need to replace vast fluid losses from vomiting and diarrhea with intravenous fluids.  The electrolyte potassium is added to the fluids in order to maintain electrolyte balance.  Sugar (dextrose) added as the stress of the disease may lower blood sugar, especially in a small puppy resulting in hypoglycemia. 
Antibiotics help to prevent sepsis from bacterial invasion across the intestinal lining.  Parvovirus ulcerates the intestine nothing prevents bacteria from being easily absorbed into the bloodstream.   Antibiotics cannot be given orally due to vomiting.   They either are given as injections or are added to the IV fluid bag.  
Home treatment for parvo infection is a bad idea.  Mortality rises substantially and the heavy diarrhea and vomiting lead to heavy viral contamination in the home.   I have had some survive if the owner can give subcutaneous fluids at home.
For more information about a specific case, consult your veterinarian.                           

The outside of a pet is good for the inside of a human.