Canine Distemper or Carré's Disease: Causes, Symptoms, Treatment, Prevention

Canine distemper, popularly known as distemper, is one of the most severe and contagious viral diseases affecting dogs. Canine distemper has varied clinical manifestations and can lead to severe and sometimes fatal complications.

Find out more about the causes of this disease, how it can manifest, how a definitive diagnosis is made, and what treatment options exist. Equally important, discover how to prevent the disease to protect your dog's health!

• What is canine distemper?
• Canine distemper - causes and transmission
• Canine distemper - symptoms
• Canine distemper (Carre's disease) - diagnosis
• Canine distemper treatment options
• Preventing canine distemper

What is canine distemper?

Distemper is a highly contagious and often fatal viral disease that affects domestic dogs and other carnivorous species. It is caused by the Canine Distemper Virus (CDV), a member of the Paramyxoviridae family, related to the measles virus in humans and the rinderpest virus. This virus has the ability to affect multiple body systems, including the respiratory, gastrointestinal, nervous, and immune systems.

Canine distemper - causes and transmission

Canine distemper is a highly contagious viral infection that can spread rapidly within dog populations. The virus can be transmitted through several routes, each contributing to the rapid and efficient spread of the infection. The main modes of transmission are as follows:

• Direct contact: dogs can become infected through direct contact with the saliva of a sick dog, for example, by licking, biting, or other physical contact. The virus can be transmitted through nasal and ocular secretions of infected dogs. Coughing and sneezing can disperse viral particles into the air, facilitating their inhalation by healthy dogs;
• Indirect contact: the virus can survive on surfaces contaminated with bodily secretions, such as food and water bowls, toys, bedding, and other objects with which dogs come into contact. Additionally, the clothes and hands of people who have touched an infected dog can carry the virus. The virus can remain active in enclosed environments, such as dog shelters, veterinary clinics, and breeding centers, if adequate hygiene and disinfection measures are not taken.
• Airborne transmission: the virus can be spread through fine aerosol droplets released into the air by coughing and sneezing from infected dogs. These droplets can be inhaled by healthy dogs, leading to infection.

Although it does not replace vaccination, healthy and harmonious development of puppies and a strong immunity in adult dogs can be supported with the help of specific dietary supplements; discuss with your veterinarian about the opportunity to provide your dog with effective support for its well-being and quality of life!

Risk factors

There are several risk factors that should be considered when discussing the prevention of canine distemper, or when there is a suspicion of diagnosis:

• Age: young dogs, especially those under six months of age, are most vulnerable to infection because their immune system is not fully developed and, in many cases, they have not yet been fully vaccinated;
• Incomplete vaccination: dogs that have not been vaccinated or have an incomplete vaccination schedule are more susceptible to infection. Regular vaccination is essential to ensure long-term immunity;
• Environment: dogs living in crowded environments, such as shelters, dog kennels, and those frequenting dog parks, have an increased risk of contracting the disease due to close contact with other animals;
• Compromised immune system: dogs with weakened immune systems, either due to chronic diseases or severe stress, are more susceptible to infection and the development of severe complications.

Can canine distemper be transmitted to humans?

Given the impressive clinical picture, a frequently asked question by veterinarians is whether canine distemper can be transmitted to humans. Canine distemper is not transmissible to humans, as the virus is specific to dogs and other carnivores, such as foxes, wolves, and raccoons.

The virus does not have the ability to infect humans, being adapted to infect only the cells of its natural hosts. The molecular structure and mechanisms of viral entry into cells are specific to receptors found on carnivore cells, which are absent from human cells, preventing viral attachment.

Canine distemper - symptoms

Symptoms of canine distemper are varied and variable. They differ depending on the stage of the disease and the affected organs and organ systems: respiratory system, gastrointestinal tract, nervous system, and sometimes the skin.

Initial symptoms of canine distemper

The initial symptoms of canine distemper are non-specific. One of the first signs of infection is fever, which is recurrent in some situations. Affected dogs often show a decrease in appetite or anorexia, are lethargic and apathetic, refuse to play, and are not even enthusiastic about a potential walk.

Sometimes, your dog's lack of appetite can signal a serious health problem. Other times, however, it may result from boredom or high outdoor temperatures. Test wet dog food and supplement your furry friend's regular diet to help them through these periods!

Respiratory symptoms of canine distemper

In the respiratory form of distemper, serous or purulent nasal and ocular secretions are common symptoms. The eyes are often red and inflamed due to conjunctivitis. The dog exhibits a persistent cough, sometimes with expectoration, affecting the upper or lower respiratory tract.

In severe cases, the dog may show dyspnea, labored or wheezing breathing, a sign of possible pneumonia.

Gastrointestinal symptoms of canine distemper

The digestive form of distemper is frequently encountered in practice. Owners complain that their pet is vomiting, often in an advanced state of dehydration. Diarrhea, sometimes bloody, is another common symptom that can lead to fluid and electrolyte loss. In this case, differential diagnosis with parvovirus, another viral disease affecting the same age range, is necessary.

Neurological symptoms of canine distemper

Canine distemper can also spread to the nervous system, causing concerning central symptoms. Dogs may become confused, disoriented, or exhibit behavioral changes, such as aggression or extreme lethargy.

Seizures are another sign of central nervous system involvement. They can range from mild tremors to severe epileptic fits. Dogs may show uncoordinated movements or lameness, indicating cerebellar involvement. Partial paralysis can occur in advanced stages of the disease. In dogs that survive the neurological form, some repetitive tics may persist for the rest of their lives.

Cutaneous symptoms of canine distemper

Cutaneous symptoms in canine distemper often go unnoticed or are underdiagnosed, given the rest of the clinical picture. The appearance of skin rashes or pustules and thickening of the skin on the nose and paws, called hyperkeratosis, is observed and considered characteristic of chronic infection.

Canine distemper (Carre's disease) - diagnosis

Diagnosing canine distemper is essential for initiating treatment and preventing the spread of the disease. Due to the wide spectrum of symptoms and similarities with other conditions, diagnosis can be complex and requires a detailed approach.

The veterinarian begins by gathering detailed information about the dog's medical history, including any observed symptoms, vaccination history, and possible exposure to unvaccinated dogs.

A complete clinical evaluation is necessary to observe physical signs of the disease, such as nasal and ocular discharge, coughing, fever, vomiting, diarrhea, and neurological symptoms. Thoracic radiography can be used to assess lung status and detect any signs of pneumonia.

Confirmation of the diagnosis is made with the help of laboratory tests:

• Serological tests (ELISA and immunofluorescence tests) can detect the presence of specific antibodies against the virus, indicating a current or recurrent infection, and the presence of viral antigen in cells collected from ocular, nasal secretions or other tissues;
• The PCR test is a highly sensitive molecular test that can detect the genetic material of the Canine Distemper Virus in blood samples, cerebrospinal fluid, nasal secretions, or other tissues. It is one of the most accurate tests for diagnosing acute infection;
• Hematological tests: a complete blood count may show non-specific changes such as leukopenia, indicating a severe viral infection. Serum biochemistry may reveal abnormalities in liver or kidney function if they are affected by the disease;
• Examination of cerebrospinal fluid may reveal meningeal inflammation or the presence of specific antibodies.

Differential diagnosis in canine distemper

Due to the similarity of symptoms with those found in other diseases, it is important to exclude other conditions that may evolve with similar signs, such as:

• Parvovirus: can cause severe diarrhea and vomiting, but mainly affects young unvaccinated dogs and can be differentiated by specific parvovirus tests;
• Canine infectious hepatitis: can cause respiratory and hepatic symptoms and is diagnosed by specific serological tests;
• Kennel cough: a contagious respiratory condition that can cause coughing and nasal discharge, but without the systemic and neurological symptoms of canine distemper.

Treatment options for canine distemper

Canine distemper is a serious viral disease that requires a complex approach to treatment, as there is no specific antiviral treatment for the virus that causes it. There is no need to think about various remedies for distemper – cauterizing dogs' muzzles was once practiced in rural areas as a "treatment," but it is a barbaric practice, extremely painful and without any benefit.

Treatment focuses on alleviating symptoms, preventing secondary infections, and generally supporting the affected dog's health.

• Supportive care: intravenous fluid administration is essential to combat dehydration caused by vomiting and diarrhea. Fluids help maintain electrolyte balance and prevent shock;
• Nutrition: nutritional support is crucial. Dogs may require parenteral nutrition or nutritional supplements if they cannot eat on their own. Nutrient-rich, easily digestible diets are recommended; discover veterinary diets for dogs and experiment until you find a solution that pleases your pet;
• Symptom control medications: antipyretic medications (to reduce fever) can be administered to control the dog's body temperature. Antiemetics are used to reduce vomiting. Antidiarrheals are used in cases of severe diarrhea. Antibiotics for distemper are used to prevent secondary bacterial infections, but they are not, strictly speaking, a treatment for canine distemper, as antibiotics do not treat viral infections;
• Antiviral and immunomodulatory drugs: although there is no specific antiviral for canine distemper, some antiviral drugs (such as ribavirin) have been used experimentally. In addition, immunomodulators can be used to stimulate the dog's immune system;
• Treatment for neurological symptoms: in cases of seizures, anticonvulsant medications (such as phenobarbital or diazepam) are essential for controlling seizures and reducing the risk of injury;
• Anti-inflammatory drugs: corticosteroids (such as prednisolone) can be used to reduce cerebral inflammation in severe cases of neurological involvement, although their use must be carefully monitored due to potential side effects and impact on the immune system.
• Palliative care and comfort: in cases where the prognosis is extremely guarded, palliative care may be considered to ensure the dog's comfort. This may include analgesics for pain control and emotional support for the animal and owner.

How long does a dog with distemper live?

Veterinarians are often asked by owners how long a dog with distemper lives. The prognosis varies significantly and depends on several factors, including the stage of the disease, the severity of symptoms, the response to treatment, and the dog's overall health condition. Canine distemper is a severe viral infection, and the prognosis can be guarded, especially in severe cases.

If the disease is diagnosed and treated at an early stage, the dog has a greater chance of recovery. In advanced stages, when the virus has already affected the respiratory, gastrointestinal, and/or nervous systems, the prognosis is less favorable.

Dogs that respond well to supportive treatment, including intravenous fluids, antibiotics for secondary infections, and anticonvulsants for neurological symptoms, have a higher chance of survival.

Young dogs and those with compromised immune systems are more vulnerable and have a higher risk of severe complications. Healthy adult dogs have a better ability to fight the infection.

Dogs that receive appropriate treatment and recover can live a normal life, although they may have long-term sequelae, especially neurological ones.

Preventing canine distemper

Canine distemper can be effectively prevented through a combination of vaccination, hygiene, and management measures.

Vaccination

Puppies should be vaccinated for canine distemper at 6-8 weeks of age, with boosters every 3-4 weeks until 16-20 weeks of age. After the initial series of vaccinations, dogs should receive annual boosters or as recommended by the veterinarian. Some vaccines offer longer protection and can be administered every 3 years.

Most canine distemper vaccines are part of combined vaccines (DHPP or DAPP), which also protect against canine infectious hepatitis, parvovirus, and parainfluenza.

Hygiene and management measures

Avoid contact of unvaccinated or partially vaccinated dogs with unknown or potentially infected dogs, especially in parks, dog playgrounds, kennels, and other public places.

Regularly disinfect surfaces, equipment, and areas where dogs stay. Effective disinfectants for distemper include chlorine solutions, quaternary ammonium, and other common disinfectants.

Wash your hands after handling dogs and contaminated equipment to prevent the spread of the virus.

Management of exposed or infected dogs

Dogs suspected of distemper infection must be immediately isolated from other dogs to prevent the spread of the disease. New dogs or dogs that have been in contact with unknown animals should be quarantined for a period before being introduced into the community.

Canine distemper, or distemper as this severe viral disease is also known, can be prevented through correct vaccination and adherence to basic hygiene rules. The disease has a severe course in most cases, and specialized care can save the dog or, at worst, alleviate its suffering. The prognosis of the disease is highly variable and entirely dependent on individual immunity.

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Sources:

1. https://www.petmd.com/dog/conditions/respiratory/distemper-in-dogs
2. https://www.avma.org/resources-tools/pet-owners/petcare/canine-distemper#:~:text=Canine%20distemper%20is%20a%20contagious,at%20risk%20of%20canine%20distemper
3. https://www.akc.org/expert-advice/health/distemper-in-dogs/