Canine distemper

Canine distemper is a viral disease that can occur in dogs, martens, skunks, seals and small bears. It is called after the discoverer of her distemper pathogen Henri Carré as Carrésche disease, in English ( canine ) as. Characteristic of the disease include high fever and fatigue. Depending on the organ system infested diarrhea and vomiting or respiratory symptoms may occur. In the course may result in damage to the brain with central nervous symptoms.

Pathogen

The disease is caused by the canine distemper virus (CDV, Canine Distemper Virus ). The pathogen is a morbillivirus of the subfamily of Paramyxovirinae. It is closely related to the measles virus in human, bovine rinderpest and the seal distemper virus, which was responsible for mass Seehundesterben in 1988 in the North Sea. Outside the living organism of the pathogen only a few days remain infectious. While he is quite resistant to drying and cold, he is inactivated rapidly by all common disinfectants.

Pathogenesis

From the disease that primarily affects young dogs aged period of eight weeks are affected to six months. The incubation period is usually between three and seven days. After the virus was absorbed through the mouth or nasal mucosa, it multiplies first in the tonsils or the bronchial. Four days after infection, viraemia occurs, are populated with the consequence mainly of the immune system tissue such as the spleen, thymus, bone marrow, lymph nodes, or Kupffer cells. Can the body within the first nine days to make enough antibodies are generally formed from any disease symptoms. Failing the production of antibodies, attacks the pathogen in addition to the digestive and the nervous system and the respiratory system and the urogenital tract. As from this time include all secretions and excretions of the dog virus material, the disease can continue to spread in the population.

Course of the disease

Depending on the affected organs varying course be observed, but can also occur in combination. Common to all is the occurrence of high fever, which may rise up to 41 ° C, and loss of appetite and apathy.

• Gastrointestinal tract: diseases of this organ system are the most common and first signs of distemper infection; they express themselves in acute diarrhea and violent vomiting.

• Respiratory: distemper expressed in this organ system with sneezing, coughing, shortness of breath, nasal discharge, "Back bubbles ", wheezing and aggravated respiratory sounds. Added to can come conjunctivitis.

If it remains in these two forms, the disease takes a comparatively mild course and after two to four weeks of recovery often result. However, if the nervous system affected, the prognosis is much less favorable and often ends with the death of the animal.

• Nervous system: the disease is characterized by changes in the eye ( optic nerve damage, changes in the retina ), spinal cord (leading to paralysis and ataxia ); in addition, there is evidence of brain disease: head tilt, loss of cranial nerves, nystagmus, hypermetric, epileptiform seizures, depression, blindness and rhythmic muscle tremor ( " distemper tick" ).

Associated with severe forms are hyperkeratosis in the field of bales and the nose leather, the so-called hard pad disease. They can be seen as unfavorable prognostic sign. Since the viruses infect the cells responsible for the formation of teeth ( ameloblasts ), occurs after a recovering from a pup infection often a distemper teeth on, which is characterized by extended defects of the enamel of dogs.

As a late result of a CDV infection can occur in older dogs rarely a chronic progressive inflammation of the brain (encephalitis); one speaks of Old Dog Encephalitis ( ODE). In these dogs, the canine distemper virus from not closely examined reasons may persist permanently in the brain and causes progressively worsening neurological symptoms. Viruses are thereby not excreted, so that such dogs for other dogs are not contagious.

In minks, ferrets and raccoons, the infection is usually fatal.

Diagnosis

The diagnosis of canine distemper disease is extremely difficult. A clinical suspicion can be expressed with appropriate symptoms and a missing or incomplete immunization. Serological tests are in vaccinated animals without significance, since it can not distinguish between antibodies to infection or vaccination. A direct detection of virus in the blood may be negative in the late phase of infection, when the viremic phase is already over. The safest diagnosis can be made on living animals by detecting viral RNA by RT- PCR in blood and cerebrospinal fluid.

Prophylaxis

Vaccinations are the primary prophylaxis, precisely because the disease has occurred increased again in recent years. Therefore, dogs should be protected by a basic immunization and subsequent re- booster vaccinations. Because puppies often have a very long time over protection by maternal antibodies, the right time for the start of a primary vaccination may vary. The Standing Committee on Vaccination vet. but recommends a vaccination at the age of eight weeks, four weeks later, the second dose and at 16 weeks, the third vaccination and a refresh after 15 months for young dogs. From the second year of life, a rejuvenation in three yearly intervals is sufficient. Should a puppy be vaccinated for the first time after twelve weeks of life, rich two vaccinations, given between three to four weeks as well as a refresher after a further year for primary immunization. There are now even vaccines, for example Nobivac SHP, where a vaccination at the age of 12 weeks or is sufficient for the primary immunization and is then repeated every three years.

Ferrets can be vaccinated from the tenth week of life against distemper. Here is a vaccination on an annual basis shall be deemed sufficient.

In dealing with sick animals strict hygiene is necessary to prevent the spread of viruses. The treatment is used with serum antibodies and interferons to therapy against the accompanying diseases and complications infusions and the administration of antibiotics are indicated.

In cases where a union is exposed to a high infection pressure, it is possible to vaccinate the puppy as early as the age of six weeks with human measles vaccine. Due to the close relationship of canine distemper and measles viruses that vaccination provides protection against a clinical distemper disease: Due to the slightly different antigens of the vaccine is not inactivated in any significant way from the at that time still existing maternal antibodies and stimulated the formation of an immune response that is clinically effective against the distemper virus. The experimental infection of dogs with measles virus results in the formation of immunity against distemper.