Canine herpesvirus is a fairly common viral infection of dogs that typically causes sudden death in puppies 1-3 weeks of age.  This virus is similar to herpesviruses in other animals, but occurs only in domestic and wild canines.  It is easily killed in the environment by most disinfectants, but in its’ host, it usually causes a fatal (pups) or lifelong sub-clinical (adult dog) infection.

The incurable nature of this disease contributes to its’ persistence and incidence.  Adult dogs likely transmit the disease through nasal, oral, ocular and vaginal secretions- especially during stressful times.  Once infected, adult dogs usually show no symptoms, mild respiratory symptoms, or genital blisters.  They quickly develop immunity to the virus (symptoms usually disappear), but cannot totally eliminate the virus from their system.  Another unique feature of the virus is its’ limited ability to proliferate at or above the normal body temperature of the adult dog (102 degrees).  Thus, a mild fever helps to control the virus.  When a female is first infected, her litter will usually be infected also.  She then develops immunity which will usually protect future litters through colostral antibodies (milk) even though the disease still persists in her body.

Puppies usually acquire the infection at or soon after birth, although abortions can occur.  The newborn does not have the ability to regulate its’ own temperature, produce a fever, or mount an immune response.  The disease is thus very severe causing weakness, crying, depression, and sudden death at 1-3 weeks of age.  Older pups (greater than 2 weeks) exposed to the virus are relatively resistant and usually develop only minor symptoms.

Diagnosis is achieved through clinical history, physical exam, necropsy (autopsy), and laboratory diagnosis.  Treatment is typically unrewarding in eliminating the virus from adults or saving affected puppies.  Elevating the environmental temperature (98-100 degrees) of puppies already infected may or may not reduce the severity of the infection.  It is more likely to be beneficial as a preventative measure for unaffected pups, however the well-being of the female should be considered at these higher temperatures.  Injecting exposed pups with immune serum from infected, immune adults may also help as a preventive measure.  Antiviral drugs are typically unsuccessful and no effective vaccine has been produced.  On a practical basis, eliminating canine herpesvirus from a kennel is not possible.  Consult your veterinarian for specifics on diagnosis and treatment.