Q&A: Distemper in dogs and cats

If you’ve heard the term “distemper,” but aren’t sure of its meaning when it comes to dogs and cats, this Q&A can help clear up the confusion.

Q: What is distemper?

A: Distemper is a viral disease that can cause severe illness and be deadly for pets. It often attacks the most vulnerable. Unvaccinated puppies and kittens are at the highest risk of developing the most severe forms of the disease.

Since the virus that infects dogs with distemper is different from the one that sickens cats and these viruses affect dogs and cats differently, it is regarded as two different diseases.

Distemper in dogs

Q: What are the symptoms of distemper in dogs?

A: The classic symptoms of canine distemper most commonly involve the respiratory tract and also include nasal discharge, conjunctivitis, cough, and fever. These signs may progress to a viral or secondary bacterial pneumonia.

Other signs such as decreased appetite, vomiting, or diarrhea may occur. Hard thickening of the nose and footpads may also be seen in affected dogs.

After the initial infection, signs of neurologic disease may occur for many weeks or longer. They typically include seizures, stiff twitching of the muscles, and a motion of the jaw that makes the pet look as if he is chewing gum.

Q: How does a dog get distemper?

A: Puppies born to an unvaccinated mother are at the highest risk. Being sneezed on by an infected dog or having direct contact through licking are the most common ways for a healthy, adult dog to contract distemper.

Q: How does a veterinarian diagnose distemper?

A: A veterinarian has many tests available to determine if the virus is present, such as testing of the blood or urine.

Q: How can you protect your dog?

A: “Distemper is a deadly disease and the only good thing about it is that it’s preventable,” says Elizabeth A. Dole, DVM, DABVP, Senior Specialist, Drug Safety, Merck Animal Health.

Vaccination with the Canine Distemper Virus is the best weapon against infection. Along with Canine Parvovirus, Canine Adenovirus, and Rabies, it is considered to be a core vaccine for dogs.

The 2022 AAHA Canine Vaccination Guidelines recommends administering the first dose of vaccine to puppies as early as 6-8 weeks of age with booster vaccines given every 2-4 weeks until the pup reaches at least 14-16 weeks.

Since the last vaccine is the most critical, it’s essential to make sure your pet doesn’t miss a vaccination. Typically, puppies need a booster one year later.

The requirements for additional vaccines should be determined through risk assessment by the owner and the dog’s veterinarian.

Thanks to widespread vaccination in the canine population, distemper is not seen as often as it used to be.

Q: How do you care for a dog diagnosed with distemper?

A: Treatment of an infected dog is based on how severe the symptoms are. Some dogs may be able to receive supportive outpatient care but dogs with more severe signs may need hospitalization and intensive treatment (and should be kept in an isolation ward so they don’t infect other dogs).

Distemper in cats

Feline distemper, which is more correctly called panleukopenia (FPV), is a highly contagious, life-threatening disease in cats caused by infection with the feline parvovirus (not a distemper virus) thus, feline distemper more closely resembles parvovirus infection in dogs.

Q: What are the symptoms in cats?

A: Cats can show a broad range of symptoms, ranging from being mildly affected to sudden death. Common signs include depression, loss of appetite, fever, vomiting, and diarrhea.

Kittens and young cats are most vulnerable to the disease; the highest illness and death rates are in kittens younger than 6 months of age. Acute FPV disease in newborns may lead to “fading kitten” syndrome and may cause death within 12 hours.

Q: How does a cat catch it?

A: Outdoor cats that are exposed to the virus in their environment or by infected cats are at high risk. In-utero transmission also occurs — which means that an infected mother can infect her kittens before they are born.

FPV infection most commonly occurs when the virus enters the body through the mouth (or nose). During active disease, the virus is shed through all body secretions (feces, vomit, saliva, urine, mucus secretions) but most consistently in the feces.

Q: How can you protect your cat?

A: There’s no way to eliminate FPV from the environment, and it can survive for a year at room temperature. It also survives freezing or treatment with most commonly used disinfectants such as alcohol or Betadine. However, it can be killed on surfaces with diluted bleach.

Vaccination with the Feline Panleukopenia Virus is the best weapon pets have against infection. Along with Feline Herpesvirus-1, Feline Calicivirus, and Rabies, it’s considered a core vaccine for cats.

Essential for kittens, the 2020 AAFP Feline Vaccination Guidelines recommend administering the first dose of vaccine at 6 weeks of age or greater, then every 3-4 weeks until 16-20 weeks of age. For kittens older than 16 weeks, they recommend two doses of vaccine, 3-4 weeks apart. A booster at six months of age is recommended.

“Protecting by vaccination is not instantaneous,” Dr. Dole points out. “Pets have to go through the series. I recommend keeping puppies and kittens that have not completed their vaccination series away from areas of potential exposure.”

The vaccine also won’t protect an animal that is already infected or exposed. And pregnant cats should not be vaccinated with a modified live FPV vaccine because the virus can replicate in the unborn kittens. This can cause permanent damage in the part of the brain that affects coordination (called cerebellar hypoplasia) resulting in life-long problems with balance and walking.

Q: How do you treat a cat with FPV?

A: Because the disease decreases white blood cells that fight off infection and wipes out intestinal cells that absorb nutrients, treatment of cats with FPV is mainly in a veterinary hospital. These facilities provide supportive care such as fluids to combat dehydration and antibiotics to fight bacterial infection.

The disease may be survivable with aggressive treatment. When a cat recovers, the virus will remain alive in its urine and feces for up to six weeks, so it should be kept apart from other cats until then.