Parvo in dogs ranges in severity depending on the age and health of the dog contracting the virus. Not all dogs that acquire parvovirus will suffer from long term effects, but permanent damage to the digestive or cardiac system is a possibility.
Short Term Effects
Parvovirus is usually contracted from contact with an infected dog's stool, but the virus can live in the ground for several months, so dogs can still be infected even if the stool is no longer present. Though unvaccinated dogs of any age can contract parvo, puppies are more susceptible because they have weaker immune systems.
In the first two days that the virus survives in your dog's body, it moves to the lymphoid tissues, where it can then enter the bloodstream and move to the digestive system and bone marrow. This results in symptoms within 7 to 10 days. Symptoms include:
- Lethargy
- Lack of appetite
- Vomiting
- Fever
- Watery diarrhea, often with blood and dehydration
Long Term Effects to the Digestive System
Because the parvovirus attacks quickly regenerating cells in the intestines, there can be short term and long term damage to the digestive system. The virus resides in the mucous lining, covering essential areas needed to digest food. This prevents your dog from absorbing nutrients, resulting in severe weight loss and dehydration.
If left untreated, parvo can lead to cell death in the intestines, which can cause permanent damage of the digestive system in some cases. To combat this, make sure to give your dog adequate amounts of water to reduce dehydration and feed high-quality food, which will provide more nutrients than low-quality kibble. This will help your dog absorb the appropriate level of nutrition.
Long Term Effects to the Cardiac System
There are two different strands of parvovirus, one that attacks the digestive system and one that attacks the cardiac system. The second is more likely to lead to death.
Your dog will usually not show signs of long term cardiac damage for several years, but dogs who have contracted parvovirus can later suffer from congestive heart failure. This can be treatable, depending on how quickly the symptoms are recognized. Symptoms include difficulty breathing and lethargy, though heart trouble can often be detected through stethoscope at regular veterinary appointments.
Additional Long Term Effects
Cell death in the intestines and bone marrow of a puppy can lead to slightly stunted growth, though this is difficult to gauge since the final size of the puppy is unknown.
Parvo can also cause long term kidney or liver damage and weaken the immune system permanently. Though your dog will never get parvo again, he may be more susceptible to other diseases. In some cases, parvo can lead to death.
Though not all cases of parvo result in long term damage, it's important to prevent against this disease by vaccinating your dog and avoid dog-friendly areas before your puppy is vaccinated.