Canine Parvo Virus: The Killer disease

Maneka Sanjay Gandhi

In 1987, a street litter of a month old puppies, being fed by me, started dying at an alarming rate. The splotches of blood in their stools were diagnosed as parasitic worms. The ill-informed vet immediately gave them deworming tablets (which is a poison) and there was a rapid decline. All the pups died within 3 days, consumed by severe gastroenteritis haemorrhaging. The killer was the deadly Canine Parvo Virus (CPV).
First recognised in the 1970s, CPV is now in epidemic form. Outbreaks have been reported from all over India. Thousands of pups have died. Since government refuses to give the vaccine and government hospitals do not treat parvo cases, the animal welfare shelters are full and the mortality of these young pups crowded together is extremely high. Animals feeders simply do not have the money to give vaccines to the pups and we all stand by helplessly as they die. In a normal year only one street pup survives a litter. The rest are run over, die of starvation, poisoned or thrown away in plastic bags. This year, even that one is unlikely.
A majority of pups sold by pet shops and dog breeders have parvo. There are two reasons: the puppy has been taken away from its mother at 3 weeks of age, by breeders and sellers, to supply customers who want really small pups. If it had been nursed by the mother the pup would have developed an immunity, which would have helped his little body fight off the virus. No pet shops vaccinate puppies, and they put pups from different breeders into one cage. The dogs are bred in slummy filthy conditions. The dogs, being bred at the breeding establishments, have low immunity due to constant abuse and minimal nourishment and, are the first victims of CPV. Typically, buyers write to me when they go to get a refund and are refused, because the entire puppy trade is illegal and done in cash with no receipts.
There are two prominent strains of the canine parvovirus (CPV-2a and CPV-2b) from the genus family of Parvoviridae. It spreads through infected faeces, vomit, blood, touch, surfaces, clothing etc. Shelters, kennels, clinics, public parks are prime locations where the virus lurks. It’s favourite victim is the young pup, but unvaccinated dogs in general are vulnerable. Undetected, or diagnosed at a later stage, it is almost always fatal within 48 - 72 hours.
Parvo virus attacks the cells in the small intestine, making the intestinal wall vulnerable to bacteria in the center of the gut. The bacteria cross over into the blood stream leading to sepsis which causes organ failure. Parvo also attacks the bone marrow, causing dangerously low white blood cell counts. This denies the body the one thing it needs to fight off the sepsis.
Parvovirus is extremely contagious. It takes 10–14 days to show symptoms after contraction.
The basic clinical signs of CPV are fever or low body temperature (hypothermia) , appearance of blood in vomit and stool, abdominal pain, nausea, dehydration and lethargy. Persistent vomiting and diarrhoea cause rapid dehydration, and damage to the intestines and immune system cause septic shock. Vomit may be clear or a yellow or brown colour, and diarrhoea will often contain blood and be a light yellow or mustard coloured hue. The blood comes from intestinal bleeding and gives a particular smell to the diarrhoea.
Parvo kills by dehydration and exhaustion, as the constant attack on the intestinal tract pushes out water and electrolytes before they can be absorbed, and the vomiting and diarrhoea keep the dog from getting any rest.
This is what you need to do if you have a pup with parvo:
Parvovirus causes life threatening dehydration and anaemia. They are basically bleeding out internally while also losing the fluids/nutrients they desperately need to fight it off.
Rush to a vet.
The only thing your vet can do to treat this virus is to give IV fluids (50 ml twice a day), antivomiting and antidiarrhoea medications, often along with a sedative to buy their immune system time to fight the virus, and antibiotics to fight secondary infections. The fluid therapy can be Loparamide, Metronidazole augmented with antibiotics Cefotoxin, Cefazolin, Ampicillin, Gentamycin, Tamiflu.
Home treatment, of pushing fluids and feeding nutritional broths, isn't always enough in one so young. It only takes a day or two for a 9-week old puppy to become fatally dehydrated. Gently pull the pup's loose skin between and behind the ears on the neck and release. If the scruff falls back into its normal position within a second, he's not dehydrated and treatment is going well, so far. If it takes two or three seconds to fall back into place, he's starting to become dehydrated, the longer it takes the more dehydrated he is. If the scruff doesn't fall back into place, even after a few seconds, you have a life or death situation on your hands. His gums will be pale as well. He needs intravenous fluids and electrolytes, and FAST!
If there are absolutely no vets, or even compounders, who know how to give an intravenous injection, do this :
Hydration is what may help to keep your pup alive. Focus on it. Keep your pup warm and give fluids every half hour. If he won't drink on his own, you'll have to syringe feed the fluids. Don't give plain water as he needs electrolytes to continue his survival, and pushing straight water can decrease his survival chances by flushing out the electrolytes he already has. Give clear Pedialyte. He will also need calories to fight the infection. If he can tolerate it, you can give chicken or vegetable broth with a bit of added salt (sodium will help him to retain water) mixed with a bit of puppy milk replacer (NOT COWS MILK). Mix the milk to broth in a 1:3 ratio. Too much milk will also increase diarrhoea. But he needs those calories.
Kaopectate can be given for diarrhoea. It usually goes by weight (mg per kg). He may also need subcutaneous fluids, which is sterile saline injected just under the skin and which can be absorbed through the microscopic vascular system, bypassing the digestive tract. Find a human doctor who may be able to help with this.
Someone has suggested that you give the pup boiled and finely mashed egg yolk once a day, and increase the amount slowly. Avoid water for an hour after feeding. Don't give egg white or else the pup will vomit.
Days three to six are usually the most touch and go. If you can help him past that, he is on the road to recovery. When the dog stops retching bile he is probably improving. The lack of blood in his stool is another marker. His activity level will go up. However, recovery from parvo takes weeks. If the pup survives, most will need to eat small, frequent meals of a bland diet and continue taking anti-nausea medications until they are able to hold down their normal food (usually a week or two). Give your dog the full course of any antibiotics that have been prescribed, even if he or she appears to be back to normal. A CPV survivor will continue to shed the virus for weeks, even months. This is why strict isolation of infected animals, and quarantine wards at veterinary hospitals/clinics and animal shelters, is important. It can live in the ground for more than six months.
Shelters, clinics and houses with CPV patients must maintain strict hygiene protocols (isolation, use of bleach and disinfectants, proper disposal of waste etc.) to prevent cross contamination. Shelters and Clinics must necessarily have Isolation kennels. The persons incharge of such kennels, must not come in contact with other shelter inmates. The medical instruments, water or food bowls etc, used in the Isolation ward, must be separate and be thoroughly disinfected before being used elsewhere. Make a foot rinse at the entrance/exit of the Isolation ward - a shallow tray filled with bleaching powder mixed with water. Every new dog/pup must be duly quarantined, dewormed and vaccinated, before exposing the other animals to it.
If you are feeding a litter of street pups, stay vigilant for appearance of any parvo-related symptoms. Wash hands after handling a CPV Patient, keeping it away from other dogs/pups,
The golden rule for combating the disease is timely and regular vaccination. Puppies need at minimum three Parvo vaccines given at 3–4 week intervals, between 6 and 16 weeks of age. Some veterinarians use variations on this protocol.
In the case of unvaccinated dogs, 2 vaccination shots are recommended (first dose followed by a booster after a month). For vaccinated dogs, an annual booster vaccine is sufficient.
(To join the animal welfare movement contact gandhim@nic.in, www.peopleforanimalsindia.org)