What Is Distemper in Dogs And How to Prevent It

Canine distemper in dogs is a serious viral disease that can make life difficult for both dogs and their owners. Although routine vaccinations have made distemper less common, it still poses a real risk to unvaccinated puppies and adult dogs.

The virus attacks parts of the body, such as the lungs, digestive system, and nervous system. Because of this, distemper can be life-threatening and needs fast veterinary care.

This guide explains what canine distemper is, how it spreads, the symptoms to watch for, treatment options, and natural ways to support your dog’s recovery.

What Is Distemper in Dogs?

Canine distemper is a highly contagious disease caused by the canine distemper virus (CDV). This virus belongs to the Morbillivirus family, which also includes the viruses that cause measles in people and rinderpest in cattle.

Once a dog is infected, the virus first attacks the lungs and airways. It then spreads through the blood to other parts of the body, affecting the lungs, digestive system, immune system, skin, and nervous system.

Because distemper affects many organs, dogs often show a range of symptoms that can get worse as the disease progresses.

Distemper is especially dangerous because it weakens the immune system. This makes dogs more likely to get other infections, such as pneumonia, which can make them even sicker.

How Does Distemper Happen?

When a pup is exposed, the Distemper virus enters through the airway and heads straight for the immune system, infecting lymphoid tissue first.

This makes the disease especially dangerous. By attacking the cells that should fight it, the virus weakens the dog’s defenses before any symptoms show up. This leaves the body more open to other infections.

After the virus takes hold, it spreads through the bloodstream to the skin, the linings of the lungs and digestive system, and eventually the brain and spinal cord. This is why symptoms can appear in many parts of the body at the same time.

A protein on the surface of the virus helps it attach to receptors on the dog’s cells. This works like a key, letting the virus enter new tissues.

Tiny genetic changes in this protein let the virus adapt to different types of cells. This explains why distemper can infect many species and why it affects each dog differently.

What Causes Canine Distemper in Dogs?

Canine distemper is caused only by the canine distemper virus. Dogs catch it when the virus enters through the nose or mouth, often by breathing in droplets from a sick animal or by touching infected fluids. The virus first infects the lymphatic tissues before spreading through the bloodstream. As it travels, it attacks several organs and tissues, including:

• lungs
• stomach
• intestines
• urinary tract
• skin
• eyes
• brain

How much harm the virus causes depends on the dog’s age, immune system, and vaccination status.

Domestic dogs are not the only animals that can carry the virus. Several wild animals, such as raccoons, foxes, coyotes, skunks, wolves, and ferrets, can also become infected.

These wild animals can carry and spread the virus, especially in areas where they often come into contact with pets.

How Does Distemper Spread?

Canine distemper spreads easily between animals. The virus mainly travels through the air when a sick dog coughs or sneezes. Healthy dogs can catch it just by breathing in these droplets.

The virus can also spread through contact with saliva, nasal discharge, urine, or eye fluids from an infected dog. Sharing bowls, toys, bedding, or other items increases the risk, especially in places with many dogs.

Dogs with distemper can spread the virus before they show obvious symptoms, making it hard to know which dogs are contagious. They may continue to spread the virus for weeks, even as their symptoms change.

Puppies and dogs in shelters, kennels, rescues, or other crowded places are at higher risk because they are around more animals. Dogs that spend time near wildlife or encounter wild animal droppings are also more likely to get infected.

Which Dogs Are Most at Risk?

Any dog can get distemper, but some groups are at much higher risk than others.

• Puppies

Puppies between 6 weeks and 6 months old are at the highest risk. At this age, the protection from their mother fades before they finish their vaccines. Without enough immunity, puppies are more likely to get sick and have more severe symptoms.

• Unvaccinated dogs

Dogs that have not been vaccinated or have missed booster shots are much more likely to get distemper. Vaccination remains the best way to prevent this disease.

• Dogs with weakened immune systems

Older dogs and those with weak immune systems have a harder time fighting the virus. Chronic illness, poor diet, or medications that lower immunity can increase the risk of serious problems.

• Dogs frequently around other animals

Dogs that often visit parks, daycare, kennels, grooming salons, shelters, or hunting areas are around more animals and have a higher chance of catching the virus. Contact with infected wildlife also increases the risk.

Because distemper spreads easily, the best way to protect your dog is to keep vaccinations up to date and avoid contact with animals that might be infected.

Symptoms of Distemper in Dogs

Canine distemper symptoms can vary widely from dog to dog. Some start with mild, cold-like signs, while others become very sick quickly. As the virus moves from the lungs to the stomach and nervous system, symptoms usually get worse.

If you notice the following symptoms early, take your dog to the vet quickly:

1. Early symptoms

The first signs of distemper usually appear one to two weeks after a dog is exposed. These early symptoms look like other common illnesses, so they are easy to miss.

Common early symptoms include:

• Fever
• Lethargy or unusual tiredness
• Loss of appetite
• Watery or pus-like eye discharge
• Runny nose
• Red or inflamed eyes

Some dogs may seem better after the first fever, but more serious symptoms can appear days later as the virus continues to spread.

 

2. Respiratory symptoms

When the virus attacks the lungs and airways, many dogs develop breathing problems. Other infections are also common because the immune system is weaker.

Respiratory symptoms may include:

• Persistent coughing
• Sneezing
• Thick yellow or green nasal discharge
• Increased eye discharge
• Difficulty breathing
• Pneumonia

If your dog has trouble breathing, take them to the vet right away. Breathing problems can quickly become life-threatening.

3. Neurological symptoms

In some dogs, the virus spreads to the brain and spinal cord, causing nerve problems. These symptoms can appear during the first illness or weeks after other symptoms seem to improve.

Neurological symptoms can include:

• Muscle twitching
• Tremors
• Head tilt
• Loss of coordination
• Difficulty walking
• Seizures
• Paralysis
• Behavioral changes

Neurological distemper is often the most serious stage of the disease. Even dogs that survive may continue to have seizures, muscle twitching, or other neurological problems for the rest of their lives.

The 3 Stages of Distemper in Dogs

Every dog is different, but distemper usually progresses through 3 stages. Knowing these stages will help you recognize when the disease is getting worse and why quick vet care is important:

Stage 1: Early infection

The first stage starts when the virus enters through the nose or mouth. It multiplies in the lymph nodes, then spreads to the lungs. Many dogs have mild, cold-like symptoms at this point.

Common signs include fever, watery eyes, runny nose, tiredness, and reduced appetite. These symptoms are not specific, so distemper can look like other illnesses.

Stage 2: Gastrointestinal and respiratory disease

As the virus moves through the blood, it affects many organs. The immune system becomes weaker, so other infections can make the dog’s condition worse.

At this stage, dogs may have a persistent cough, pneumonia, vomiting, diarrhea, dehydration, and significant weight loss. Many need to stay in the hospital for fluids, food, and medicine.

Stage 3: Neurological disease

In the last stage, the virus gets into the brain and spinal cord. This can happen while the dog still has other symptoms or weeks after those symptoms go away.

Dogs may have muscle twitches, tremors, seizures, trouble with balance, head tilts, or paralysis. Neurological distemper has the worst outlook. Some dogs recover, but others have lasting nerve problems that require lifelong care.

How Veterinarians Diagnose Distemper

Because the symptoms of canine distemper can look like those of other infectious diseases, diagnosing it is not always straightforward.

Your veterinarian will consider your dog’s age, vaccination history, recent exposure to other animals, and clinical signs before recommending tests.

A physical examination is the first step. During the exam, your veterinarian will check for signs like fever, eye and nasal discharge, coughing, dehydration, and neurological problems.

If distemper is suspected, more tests may be needed to confirm the diagnosis and assess how severe the infection is.

Common diagnostic tests include:

• PCR testing, short for Polymerase Chain Reaction, which detects the virus in samples taken from the nose, throat, blood, or urine.
• Blood tests to evaluate your dog’s immune system, hydration status, and overall health.
• Chest X-rays if pneumonia or other respiratory complications are suspected.
• Urinalysis to assess organ function and look for signs of infection.
• Cerebrospinal fluid (CSF) analysis in dogs showing neurological symptoms to help evaluate inflammation affecting the brain and spinal cord.

No single test is perfect, so veterinarians often use test results along with your dog’s symptoms and medical history to make a diagnosis.

Treatment for Distemper in Dogs

There is currently no cure for the canine distemper virus. Instead, treatment focuses on supporting your dog’s immune system, managing symptoms, and preventing other infections while the body fights the disease.

The treatment plan depends on how severe the infection is and whether the respiratory, digestive, or nervous system is affected.

1. Hospital care

Dogs with moderate to severe distemper often need to stay in the hospital, especially if they are dehydrated, having trouble breathing, or showing neurological symptoms.

Hospital care may include:

• Intravenous (IV) fluids to correct dehydration
• Oxygen therapy for dogs with breathing difficulties
• Nutritional support if the dog refuses to eat
• Careful monitoring of body temperature and vital signs
• Isolation to prevent spreading the virus to other dogs

Puppies and very sick dogs may need several days of intensive care before they are stable enough to continue recovering at home.

2. Medications

Although medications cannot kill the virus, they are important for treating complications caused by the infection.

Depending on your dog’s symptoms, your veterinarian may prescribe:

• Antibiotics to treat secondary bacterial infections, such as pneumonia.
• Anti-nausea medications to control vomiting.
• Medications to reduce diarrhea and prevent dehydration.
• Anti-seizure medications for dogs experiencing seizures or other neurological signs.
• Pain medications when appropriate to improve comfort.
• Bronchodilators or other respiratory medications to help dogs with severe lung involvement.

Never give your dog human medications or stop prescribed treatments without your veterinarian’s advice.

3. Supportive care

Supportive care is important both during hospitalization and after your dog comes home. Recovery often takes several weeks, and some dogs need ongoing care long after the initial infection is over.

Supportive care includes keeping your dog hydrated, offering nutritious and easy-to-digest meals, plenty of rest, and gently cleaning their eye and nasal discharge.

Your veterinarian may also suggest follow-up visits to monitor your dog’s recovery and check for any neurological problems that may develop later.

If your dog develops new symptoms like muscle twitching, seizures, trouble walking, or trouble breathing, contact your veterinarian right away.

How to Prevent Distemper in Dogs

Since there is no cure for canine distemper, prevention is the best way to protect your dog. Routine vaccination and reducing exposure to infected animals have greatly lowered the number of cases today.

By vaccination

The canine distemper vaccine is a core vaccine, which means it is recommended for almost every dog, regardless of breed or lifestyle.

Puppies usually start their vaccination series between six and eight weeks old and get booster shots every few weeks until they are about 16 weeks old. Adult dogs also need booster vaccinations as recommended by their veterinarian to maintain long-term protection.

While no vaccine is 100% effective, vaccinated dogs are much less likely to get seriously ill if they are exposed to the virus.

By reducing exposure

Vaccines give the best protection, but it’s also important to limit your dog’s exposure to the virus. This is especially true for puppies who haven’t finished their vaccine series yet. The following tips will lower your dog’s risk of infection significantly:

• Pick boarding places, training classes, and groomers that require current vaccinations and keep your dog’s belongings clean and well-sanitized.
• Don’t bring unvaccinated puppies to dog parks, daycare, boarding kennels, grooming salons, or other places where lots of dogs are together.
• Keep your dog away from animals that look sick, and don’t let them share food bowls, toys, or bedding with dogs that aren’t well.
• Keep your dog from coming into contact with wild animals like raccoons, foxes, skunks, and coyotes, since they can carry the distemper virus.
• If your dog gets sick, keep them away from other dogs until your vet says they’re no longer contagious.

Natural Ways to Help Your Dog With Distemper

Natural remedies cannot cure canine distemper or replace veterinary treatment. However, they may help support your dog’s comfort and recovery when used along with your veterinarian’s treatment plan.

• A healthy diet: Giving your dog a highly digestible, nutritious diet can help provide the energy they need to heal, and keeping them well hydrated is especially important if they have had vomiting or diarrhea.
• A calm lifestyle: Creating a quiet, stress-free environment also encourages rest and helps the body fight the infection.
• CBD: Some owners also choose to use CBD-based products as part of their dog’s recovery plan, to promote relaxation and soothe their puppy's pain.

While CBD does not treat the virus, it may help support comfort, encourage appetite, and improve rest during recovery.

As with any supplement, talk to your veterinarian before giving your dog CBD, especially if they are taking prescription medications.

Some veterinarians may also recommend probiotics to help restore healthy gut bacteria after antibiotics or omega-3 fatty acids to support overall health and reduce inflammation.

Innovet’s Advanced Probiotic Chews combine probiotics, prebiotics, digestive enzymes, pumpkin, and sweet potato to support healthy digestion, balanced gut bacteria, and regular stool. The chews also contain hemp extract and are designed as an easy daily supplement for dogs.

Shop Probiotic Chews for Dogs →

⚠️ Only give these supplements under your veterinarian’s guidance, since every dog’s condition is different.

Innovet CBD Can Help Your Dog Recover

Innovet’s CBD is not a cure for distemper and should not replace veterinary care. However, with your veterinarian’s approval, you can use it alongside your dog’s treatment plan to support their overall wellness during recovery.

Here are some options you might find helpful:

• CBD Oil for Dogs: Dogs recovering from distemper may feel stressed or uncomfortable, lose their appetite, or have trouble resting. CBD’s calming effects may help them relax, eat better, and feel more comfortable as they recover.

Shop CBD Oil for Dogs →

• CBD Soft Chews and Treats: If your dog doesn’t like taking oil, CBD soft chews and treats are a convenient option. They offer the same possible wellness benefits in a tasty, easy-to-give form, which can be helpful for dogs recovering at home.

Choose from a variety of CBD Soft Chews here →

• CBD Paw Balm: Dogs recovering from distemper may develop dry, cracked paw pads or hard pad disease, a condition that causes the paw pads to thicken and harden. CBD paw balm helps moisturize dry paws, soothe irritation, and support healthier skin as part of your dog’s overall recovery routine.

Shop CBD Paw Balm here →

⚠️ Always talk to your veterinarian before giving your dog CBD or any supplement, especially if your dog is taking prescription medications for distemper or other health issues. Your vet can help you decide if CBD is right for your dog’s recovery plan.

If you have questions about which CBD product to choose or how much to give, you can reach our team at (310) 817-5731 for help.