Distemper

About Distemper

Canine Distemper is a viral, worldwide disease that is highly contagious, despite the long existence of a highly effective vaccine. The virus can attack the respiratory, gastrointestinal, and nervous systems of infected animals, and can often be fatal even with significant treatment and supportive care. 

Testing Method

Dogs are being tested using PCR (polymerase chain reaction) tests. This method involves amplifying specific DNA codes that corresponds to the virus in question from samples taken from the animals using a swab of the conjunctiva (eye lid) and pharynx (upper respiratory tract).  These tests are very sensitive and specific as they only amplify the DNA of the distemper virus and other respiratory pathogens that may be causing secondary infections. This test is also capable of differentiating between an active viral infection causing disease and the immune response caused by the distemper vaccine these animals receive upon intake into the shelter system. 

Possible results include the following:

  • CDV Wildtype Infection (High positive): The canine distemper virus (CDV) viral load is high, well above levels seen with vaccine interference. The positive CDV PCR result is most likely caused by a wildtype strain and indicates infection.
  • Indeterminate: Canine Distemper virus (CDV) viral load is indeterminate – above levels seen with vaccine interference, but below the levels typically seen with wild type infection.
  • Low CDV Positive: Canine distemper virus (CDV) viral load is low, which is possible with early infection, resolving infection, or vaccine interference if the dog has been vaccinated with in the last 2 weeks. If the dog hasn’t been vaccinated this is consistent with very early or the recovery phases of infection. 

Guidelines we are following to control outbreak:

These guidelines have been developed in consultation with other shelters in the central Texas area that have dealt with this situation and two local private practice veterinarians.

  • Dogs that have a negative PCR test for distemper and are not showing clinical signs of distemper or associated upper respiratory infection will be isolated away from positive dogs and will be up for adoption.
  • Dogs that receive high positive PCR test will be humanely euthanized to reduce further vector spread of the disease.
  • Dogs that receive an indeterminate PCR test result with significant clinical signs will be humanely euthanized to reduce further vector spread of the disease.
  • Any dogs that develop obvious neurologic signs will be humanely euthanized.
  • Dogs that receive an indeterminate PCR test with no clinical signs will be isolated as effectively as possible and reevaluated daily and retested in 1 to 2 weeks.
  • Dogs that receive a low positive test will be evaluated based on their symptoms and the time in proximity between testing and vaccination. These dogs will also be isolated as effectively as possible. They will be reevaluated daily and retested in 1 to 2 weeks.
  • Any dog that is showing symptoms of a possible upper respiratory infection, regardless of distemper status, will be treated appropriately with supportive care and antibiotics to prevent further infection. 
  • Any dogs whose conditions worsens despite care to the point that their prognosis for recovery is poor or grave, will be humanely euthanized to avoid unnecessary suffering.