Canine herpes virus (CHV) is a common systemic viral infection in dogs that can cause a variety of symptoms, including respiratory disease, eye problems, and genital ulcers. CHV is also the leading cause of fading puppy syndrome, a condition that often leads to miscarriage/abortion, stillborn puppies or the death of newborn puppies. CHV can be found in dogs, wolves, and coyotes and is not infectious to humans. It's transmitted through direct contact, which is why I try not to allow my pregnant dogs within sniffing distance of dogs outside my home.
Adult dogs with healthy and fully developed immune systems typically show no symptoms from CHV infection and have no lasting effects. Older dogs may have kennel cough-type symptoms. However, in puppies it is very severe and often fatal, particularly in puppies 3 weeks old or younger.
Symptoms of CHV in Puppies
The incubation period for CHV is 2-10 days. During this time, puppies may appear healthy and show no signs of illness. However, once the illness begins, symptoms can develop quickly and include:
* Fever
* Respiratory distress
* Discharge from the eyes or nose
* Loss of appetite
* Depression
* Diarrhea
* Vomiting
Mortality is high in young puppies
The disease hits quickly in young puppies and they can die within a day of onset. Even if they survive, puppies can suffer from irreversible damage to kidney, liver, brain, and lymph nodes and puppies that survive often exhibit neurological symptoms or blindness.
While there is no cure for CHV, prompt treatment can help relieve symptoms and improve the chances of survival for affected puppies, although treatment isn't usually very effective. Whelping bitches (female dogs who have recently given birth) should be closely monitored for signs of CHV infection, as they are at an increased risk of passing the virus on to their litter.
Young puppies can not maintain their own body temperature well, and this allows the CHV to infect them. The cooler the body temperature, the easier it is for the virus to replicate, which is why younger puppies are at higher risk.
Your best protection for your puppies is to keep pregnant dogs away from other dogs during their last trimester and the first 3 weeks after puppies are born. You should also ensure you have good biosecurity procedures for visitors, including show baths and hand washing.
Treatment of CHV in Puppies
There is no specific treatment for CHV, and there is no cure. Puppies who contract the virus will need supportive care to help them through the illness. This may include fluids to prevent dehydration, antibiotics to treat secondary bacterial infections, and medications to control fever and vomiting. In some cases, puppies may need to be hospitalized for intensive care.
Although it is a deadly disease, your veterinarian will still give your puppies some medication and treatment to lower the risk of death. Treatment for herpes virus includes:
1. Antiviral medications
2. Eye drops
3. Cough medications
4. Pain relievers
5. Treating puppies with the antibodies of a herpes-recovered mother
6. Keeping the body temperature of the puppies warm or above 95 degrees
It's critical to quarantine any sick puppies and avoid contact with them until they have recovered. If you must handle sick puppies, be sure to wear gloves and wash your hands and clothing thoroughly afterwards. You should also disinfect any surfaces that sick puppies have come into contact with.
Unfortunately, even with treatment, many puppies will not survive.
Prevention and vaccination
The best prevention is to keep pregnant dogs away from infected dogs, particularly in the last trimester of pregnancy and first three weeks after the puppies are whelped.
There is a vaccine available for CHV in Europe, but it is not available in the United States. After initial infection, the bitch will develop antibodies and these will pass on to her puppies through her colostrum. However, unless you have a confirmed case there's no way to know if your bitch has had a CHV infection and has antibodies, so it's always best to act as if she's at risk since she may be.
Similar conditions
Brucellosis and toxoplasmosis are other infections that can have similar effects on a litter. Both brucellosis and toxoplasmosis are transmissible to humans, unlike CHV. Any puppies that die suddenly should have a necropsy to determine the specific cause of death.
If you think your dog or puppies may be infected with canine herpes virus, please contact your veterinarian immediately for further testing and treatment recommendations.