Distemper in Dogs

Dogs are the natural host for CDV and are thought to be the source of infection for other carnivorous wildlife. Cases of non-canine CDV infections are uncommon.

Canine distemper is a highly contagious and common viral disease that affects dogs worldwide. Distemper vaccines are extremely effective and the disease in vaccinated dogs is extremely rare.

Due to CDV’s highly contagious nature, dogs infected with CDV need to remain in isolation for several months to stop the spread of the virus. Persons exposed to CDV should exercise biosecurity protocols such as wearing protective clothing and gloves, disinfecting areas where the infected dog resides, and washing hands frequently.

Symptoms like hardening of the pads or nose, muscle fasciculations (“knots” in the muscles), or declining neurological function can develop weeks to years after the active infection has resolved.

Dental enamel abnormalities are common with puppies who survive distemper while their teeth are developing.

Distemper usually develops in unvaccinated or immunocompromised dogs.

Examination by a veterinarian as soon as possible is important as CDV can be deadly, even with timely treatment.

The distemper virus is responsible for development of CDV. Dogs are the natural reservoir for CDV and spread the virus most commonly through aerosolized droplets of respiratory secretions. Infected dogs can shed viral particles in almost all bodily fluids.

CDV most commonly affects the respiratory system, but also affects the neurological and gastrointestinal systems, as well as the eyes and skin.

Symptoms depend on what part of the body is affected and how effective the immune response is. Fifty percent of dogs that are infected with distemper will show no symptoms.

Diagnosis typically involves bloodwork, urinalysis, and X-rays. If CDV infection is suspected, swabs from the eyes and throat or a specific blood test can confirm the presence of CDV.

Treatment is primarily supportive until the immune system can clear the virus. Medications for nausea, secondary bacterial infections, IV fluid therapy for dehydration, and anti-seizure medication are used if indicated. Paralyzed patients require intensive nursing care.

Duration of CDV symptoms varies greatly depending on what body system is affected. Respiratory and gastrointestinal signs may resolve in a couple of weeks if an effective immune response is mounted. Dogs who appear to recover from the respiratory form may develop neurological symptoms 1-3 weeks later. Neurological symptoms are often progressive and may be permanent.

Prognosis varies greatly and is dependent on the strain of CDV and the host’s immune response. Dogs with a robust immune system may have only mild disease symptoms. Some infected dogs never have symptoms at all.

Immunocompromised canines tend to develop severe disease. Mortality is up to 50%, even with treatment. Pets with neurological symptoms such as seizures, incoordination, or paralysis have a very guarded prognosis.

Vaccination against CDV according to veterinary recommendations is inexpensive, readily available, safe, and very effective in preventing the disease. Vaccinating mother dogs prior to breeding provides the puppies with some degree of protection when they are born.

CDV is primarily spread by respiratory secretions, but spread through any bodily fluid is possible. Adhering to isolation requirements after diagnosis is essential to minimize further spread, especially in living environments where multiple dogs are housed.

CDV infections are very common in non-vaccinated dogs. CDV is very uncommon in healthy, vaccinated individuals.

Treatment consists of supportive care for secondary complications:

• Antibiotics
• Anti-nausea medications
• IV fluids therapy
• Anti-seizure medication
• Intensive nursing care for paralyzed dogs