Overview

Canine herpes infection causes reproductive problems in adult dogs, and like human herpes is an infection that will be present for life. Adult dogs usually do not appear to be sick; however, in young puppies the infection is lethal with a very high mortality rate. The virus is transmitted via direct contact, which includes normal nosing and licking in addition to sexual activities. Puppies usually contract the disease from contact with the birth canal or from the nasal and oral secretion of the mother shortly after birth. Once symptoms develop death usually follow within 48 hours. If the disease is contracted when the puppies are more than three weeks old, they have a much better chance of survival, although a latent infection might develop.

Canine herpesvirus is different from the human herpesviruses, as well as the feline one; it cannot be transmitted through the air, and there are no dangers of cross-species infection.

Symptoms and Diagnosis

In adult dogs, there are usually little to no symptoms after being infected; in rare cases the virus causes kennel cough. In most cases the infection only manifests in female dogs during pregnancy, as the virus causes spontaneous abortion and stillborn puppies. Sometimes the virus causes resorption of the litter during pregnancy. It is difficult to test adult dogs for the virus, since like the human herpes it recedes and becomes undetectable. Testing for the presence of antibodies indicates if the dog has been previously exposed to the virus, and can help determine if the dog is having an active infection.

Puppies infected by canine herpes display symptoms including crying, coughing, vomiting, nasal discharge, and loss of appetite. Bruising of the belly and eye lesions may also occur. In puppies less than one week old the mortality rate approaches 80%. The only reliable way to pinpoint a canine herpes infection in puppies is an autopsy.

Treatment

Since death occurs rapidly in infected puppies, very few treatment options are available. Keeping the puppies warm may help since the virus requires low temperature to survive. Antiviral medications or antibodies from another dog might also help. The best way to combat this disease is through prevention, since the canine herpesvirus does not survive long in the environment and can easily be destroyed by household detergents.

If a pregnant female has already been exposed to the virus prior to pregnancy, she usually has sufficient antibodies that can be transferred to the puppies. The puppies are most at risk if the mother contracts the virus during pregnancy, or if other dogs in the same household carry the virus. Therefore, it is important to isolate a pregnant female from other dogs when late in pregnancy, and during the first three weeks after birth, especially if she has no prior exposure to the virus.