26 Common Dog Diseases

Dog parents, this informative article is for you… Regardless of the dog breed, this article lists 26 common dog diseases, their causes, symptoms, and preventive measures. Learning about these dog illnesses will help you identify warning signs early, seek timely veterinary care, and implement prevention like vaccinations, parasite control, and balanced nutrition.

 

Veterinary professionals, this article is also for you to review these common dog diseases. You can add information and suggest alternative precautionary steps.

 

So, without any further delay, let’s move on to read about the 26 common dog diseases!

 

Dogs are susceptible to various diseases that can upset their quality of life and, in severe cases, become life-threatening.

 

From viral infections like canine parvovirus and distemper to chronic conditions such as arthritis and diabetes, many diseases have roots in genetic predisposition, poor diet, lack of vaccinations, or environmental factors.

 

On the other hand, some illnesses, like leptospirosis and Lyme disease, spread through contaminated water or tick bites. A few others, such as bloat (GDV) and pancreatitis, arise from dietary issues or stress.

 

Recognizing early signs can make a difference in a dog’s recovery. That is why understanding these common dog diseases is a must for every dog parent.

 

Common Dog Disease Categories

 

There are various categories of dog diseases based on their cause. However, in this article, we’ll discuss 4 major categories of dog diseases. Identifying these categories will help dog owners detect, prevent, and treat diseases early.

 

• Viral Dog Diseases – Spread through contact with infected saliva, feces, or air
• Bacterial Dog Diseases – Infect through bites, contaminated water, or wounds
• Parasitic Dog Diseases – Attack through worms, fleas, or ticks
• Genetic and Metabolic Disorders in Dogs – Develop because of hereditary or hormonal issues

Let’s discuss some of the most common dog diseases for each category…

 

Common Viral Dog Diseases – Causes, Symptoms, & Prevention

 

• Canine Parvovirus – An Infectious Viral Disease

Canine parvovirus, or Parvo, is a contagious viral disease and mostly affects puppies and unvaccinated dogs. It spreads through direct contact with infected feces, contaminated surfaces, and even human clothing or shoes. Once the virus enters a dog’s system, it attacks the intestinal lining, leading to severe gastrointestinal pain.

 

Infected dogs suffer from persistent vomiting, bloody diarrhea, extreme lethargy, fever, rapid weight loss, and dehydration. In severe cases, the virus can even attack the heart muscle, resulting in sudden death, especially in young puppies.

 

The best way to prevent parvovirus is through vaccination. The DAPP vaccine provides strong protection when administered as a series of shots during puppyhood and followed by regular boosters.

 

• Canine Distemper – A Contagious Viral Infection

Canine distemper is a contagious and most dangerous viral infection in dogs. It spreads through airborne droplets, direct contact with infected animals, or contaminated objects like food bowls. The virus attacks the respiratory, nervous, and gastrointestinal systems of dogs. Puppies and unvaccinated dogs are at the highest risk, and once infected, the disease can progress rapidly.

 

Early symptoms of Canine Distemper include watery eyes, nasal discharge, fever, coughing, vomiting, and diarrhea. As the infection worsens, dogs may develop neurological signs such as muscle twitching, seizures, and paralysis. In severe cases, the virus causes a hardening of the nose and paw pads, a condition known as hyperkeratosis.

 

The DAPP vaccine is the most effective way to prevent canine distemper. Dog owners should also avoid exposing unvaccinated puppies to unfamiliar or stray dogs, as the virus spreads easily in shelters, parks, and kennels.

 

• Kennel Cough – A Respiratory Infection
  

Kennel cough, or canine infectious tracheobronchitis, is a contagious respiratory infection (can be bacterial or Viral). Bordetella bronchiseptica bacteria or canine viruses such as parainfluenza and adenovirus are culprits for this infection.

 

It spreads easily in crowded environments like kennels, dog parks, shelters, and daycare centers, especially where ventilation is poor.

 

Infected dogs develop a persistent, dry, honking cough, which may worsen with excitement or activity. Other symptoms include sneezing, nasal discharge, mild fever, and lethargy, though some dogs remain active despite the cough.

 

Prevention involves vaccinating against Bordetella, particularly for dogs that frequently interact with others in group settings. Limiting exposure to overcrowded or poorly ventilated areas can also reduce the risk of infection.

 

• Rabies – An Incurable Viral Disease
  

Rabies is an incurable viral disease that spreads through bites from infected animals. It attacks the brain and nervous system. Once the virus is in the body, it causes severe inflammation, leading to progressive neurological deterioration. As the disease progresses, paralysis and seizures set in, ultimately leading to death.

 

Dogs with Rabies may show sudden aggression, excessive drooling, difficulty swallowing, and disorientation.

 

Unfortunately, once symptoms appear, rabies is always fatal. The only protection against this deadly virus is prevention. Vaccination is not only highly effective but also legally required in most regions to protect both dogs and humans. In addition, limiting a dog’s exposure to wild animals, such as bats, raccoons, and foxes, further reduces the risk of infection.

 

• Canine Influenza (Dog Flu) – A Contagious Respiratory Infection

Canine influenza, or dog flu, is a transmissible respiratory infection caused by the H3N8 or H3N2 flu virus. It spreads through sneezing, coughing, and contaminated objects like food bowls, toys, and bedding. The virus can survive on surfaces for hours, making it easy for dogs to contract the illness in kennels, dog parks, or shelters.

 

Infected dogs develop runny noses, persistent coughs, fever, and lethargy. Some may experience difficulty breathing or refuse to eat because of weakness. While most dogs recover within two to three weeks, severe cases can lead to pneumonia or secondary infections that require veterinary intervention.

 

Preventing canine influenza starts with vaccination, especially for dogs that frequently interact with others. Avoiding sick dogs and sanitizing shared items like water bowls and leashes can also reduce the risk of infection.

 

• Infectious Canine Hepatitis (ICH) – An Infectious Viral Disease
  

Infectious Canine Hepatitis (ICH) is a contagious viral disease caused by the canine adenovirus type 1 (CAV-1). The virus spreads through contact with infected saliva, urine, or feces and can survive in the environment for months. Once inside the body, it attacks the liver, kidneys, spleen, and lungs, leading to organ damage.

 

Dogs with ICH often show fever, lethargy, vomiting, diarrhea, and abdominal pain. As the disease progresses, they may develop jaundice (yellowing of the skin and eyes), swollen lymph nodes, and spontaneous bleeding. Some dogs experience cloudiness in the eyes, known as “blue eye,” due to corneal inflammation. In severe cases, the virus can cause seizures, coma, and sudden death.

 

Prevention relies on vaccination. The CAV-1 vaccine in routine shots provides strong immunity against the virus. Keeping your dog away from contaminated areas, ensuring clean drinking water, and avoiding contact with infected animals also reduce the risk.

 

Common Bacterial Dog Diseases – Causes, Symptoms, & Prevention

 

• Leptospirosis – A Bacterial Infection

Leptospirosis is a bacterial infection that spreads through contaminated water, urine, or soil. Dogs that drink from puddles, lakes, or other stagnant sources are more prone to Leptospirosis. The bacteria attacks the kidneys and liver of dogs, leading to serious complications if left untreated.

 

Infected dogs may develop fever, vomiting, diarrhea, muscle pain, and extreme lethargy. As the disease progresses, severe cases can result in kidney failure, jaundice, and difficulty breathing.

 

Preventing leptospirosis is possible with vaccination, keeping dogs away from stagnant water, and controlling rodents, which are common carriers of the bacteria.

 

• Lyme Disease – A Bacterial Infection in Dogs
  

Lyme disease is a bacterial infection caused by Borrelia burgdorferi and spreads through deer tick bites. Once the bacteria enter a dog’s bloodstream, they can spread to joints, organs, and, in severe cases, the kidneys.

 

Infected dogs may develop limping due to joint swelling, fever, fatigue, appetite loss, and, in advanced cases, kidney failure. Some dogs remain asymptomatic for months before showing signs, making early detection challenging.

 

Prevention is key to protecting dogs from Lyme disease. After walks in grassy or wooded areas, dog owners should thoroughly check their dog’s fur and skin for ticks, removing any immediately with fine-tipped tweezers.

 

• Pyoderma – A Bacterial Skin Infection

Pyoderma in dogs is a bacterial skin infection that develops when bacteria multiply in damaged or weakened skin.

 

Allergies, parasites, hormonal imbalances, poor grooming, or injuries trigger this condition. Dogs with weakened immune systems or underlying health issues also face a higher risk. The infection causes red, inflamed skin, itching, hair loss, pustules (pus-filled bumps), and scabs. In severe cases, affected areas may ooze, emit a foul odor, or become painful.

 

Regular grooming, keeping the skin dry, managing allergies, and treating parasites quickly can help prevent Pyoderma.

 

• Brucellosis – A Contagious Bacterial Infection
  

Brucellosis in dogs is a highly contagious bacterial infection caused by Brucella canis. It spreads through bodily fluids such as urine, saliva, vaginal discharge, and semen. Dogs contract the disease through mating, contact with aborted fetuses, or contaminated surfaces. Breeding dogs are at the highest risk, but any dog can become infected through exposure to an infected dog’s fluids.

 

Dogs with brucellosis show subtle or chronic symptoms. Infected females may experience infertility, miscarriages, or stillbirths, while males may suffer from swollen testicles and prostate infections. Some dogs develop lethargy, weight loss, swollen lymph nodes, or lameness because of joint inflammation. In severe cases, the bacteria can spread to the spine, causing neurological issues and chronic pain. Since symptoms vary, many infections go unnoticed until they cause reproductive failure or systemic illness.

 

Preventing brucellosis starts with strict breeding controls and regular health screenings, especially in kennels and breeding facilities. Since there is no reliable cure, spaying or neutering infected dogs helps control the disease.

 

Dog owners should also practice proper hygiene, disinfect living spaces, and avoid contact with infected fluids. Since brucellosis can spread to humans, taking precautions is important for both canine and human health.

 

• Salmonellosis – A Bacterial Infection
  

Salmonellosis in dogs happens when they consume food, water, or raw meat contaminated with Salmonella bacteria. Dogs can also carry the infection by coming into contact with feces from infected animals or through contaminated surfaces.

 

While some dogs may carry the bacteria without showing signs, others develop serious gastrointestinal issues. Symptoms include vomiting, diarrhea (sometimes bloody), fever, lethargy, and loss of appetite. In severe cases, the infection can spread to the bloodstream, leading to sepsis and organ failure.

 

Proper food handling and hygiene can help prevent Salmonellosis. Avoid feeding your dog raw or undercooked meat, clean food and water bowls regularly, and prevent dogs from searching for spoiled food.

 

• Actinomycosis – A Bacterial Infection in Dogs
  

Actinomycosis in dogs is a bacterial infection caused by Actinomyces species, commonly found in the mouth and gastrointestinal tract. This bacteria usually remains harmless but can cause serious infections when it enters deep tissues through bite wounds, surgical incisions, or foreign objects like grass awns. Dogs that dig or chew rough objects are at higher risk.

 

Once inside the body, the bacteria create painful abscesses, swelling, and draining sores, often filled with thick, yellow pus. In severe cases, bone infections (osteomyelitis) and respiratory issues may develop if the bacteria spread to the lungs.

 

Preventing Actinomycosis is possible with regular dental care, cleaning wounds promptly, and keeping dogs away from sharp objects and contaminated environments.

 

• Campylobacteriosis – A Bacterial Infection in Dogs

Campylobacteriosis in dogs starts when Campylobacter bacteria infects the intestines, leading to gastrointestinal issues. This infection spreads through contaminated food, water, or feces, especially in environments with poor sanitation. Puppies, older dogs, and those with weak immune systems are more vulnerable.

 

Many dogs carry the bacteria without symptoms, but when the infection becomes active, it causes diarrhea, vomiting, fever, and abdominal pain. In severe cases, dogs may suffer from dehydration and weight loss due to persistent diarrhea.

 

Preventing campylobacteriosis starts with proper hygiene, clean drinking water, and a well-balanced diet. Avoid feeding raw or undercooked meat, as it can harbor harmful bacteria. Regularly disinfecting food bowls, cleaning up litter, and limiting contact with infected animals also reduce the risk.

 

Common Parasitic Dog Diseases – Causes, Symptoms, & Prevention

 

• Heartworm – A Parasitic Disease in Dogs

Heartworm disease is a fatal condition caused by parasitic worms transmitted through mosquito bites. Once inside the dog’s body, these worms travel to the heart, lungs, and blood vessels, where they grow and multiply, leading to severe organ damage.

 

As the disease progresses, dogs may develop a persistent cough, exercise intolerance, fatigue, and weight loss. In advanced cases, heart failure can occur, causing fluid buildup in the abdomen, difficulty breathing, and even sudden collapse.

 

Preventing heartworm disease is far easier than treating it, as once the worms mature, treatment becomes expensive and risky. The best defense is monthly heartworm prevention medications, such as Heartgard, Sentinel, or Trifexis, which kill immature larvae before they develop into adult worms.

 

• Hookworm – A Parasitic Infection
  

Hookworm infection comes through contaminated soil, feces, and infected prey, entering a dog’s body through ingestion or skin contact. These parasites attach to the intestinal lining, feed on blood, and cause severe health issues.

 

Dogs with Hookworm infection often experience diarrhea, weight loss, anemia, weakness, and a dull coat. In puppies, a heavy infestation can be fatal because of extreme blood loss.

 

Preventing hookworm infections starts with good hygiene, regular deworming, and keeping living areas clean. Dogs should avoid contaminated environments, and owners must dispose of feces properly.

 

• Roundworm – A Parasitic Infection

Roundworm infection spreads when dogs swallow eggs or larvae from contaminated soil, feces, or infected prey. Puppies often catch it from their mother before birth or through nursing. Once inside the body, the larvae travel through organs and settle in the intestines, where they grow into long, spaghetti-like worms.

 

Infected dogs may experience a swollen belly, vomiting, diarrhea, weight loss, and a dull coat. In severe cases, roundworms block the intestines, causing life-threatening complications. Puppies are more vulnerable due to their weaker immune systems.

 

Preventing this infection requires regular deworming, proper disposal of feces, and keeping the environment clean. Avoiding raw or undercooked meat also reduces the risk.

 

• Tapeworm – A Parasitic Infestation

   

Tapeworms grow inside a dog’s intestines after ingestion of infected fleas, raw meat, or rodents carrying parasite larvae. Once inside, these worms attach to the intestinal wall, absorb nutrients, and grow in length.

 

Many dogs show no obvious signs, but some may experience weight loss, scooting, vomiting, or an increased appetite without gaining weight. Owners might notice small, rice-like worms in the stool or around the dog’s rear.

 

Preventing tapeworm infection starts with strict flea control, avoiding raw meat, and regular deworming.

 

• Whipworm – A Parasitic Infection

The Trichuris vulpis parasite is the culprit for Whipworm infection in dogs. It develops when dogs swallow eggs from contaminated soil, water, or feces. The parasite settles in the large intestine, where it burrows into the lining and causes inflammation.

 

Infected dogs show symptoms like diarrhea with blood or mucus, weight loss, dehydration, lethargy, and anemia. Severe cases can lead to painful bowel movements and malnutrition because of nutrient absorption issues. Some dogs may carry the infection without obvious symptoms.

 

Whipworm infection requires regular deworming, proper sanitation, and avoiding contaminated areas. Cleaning up feces immediately and maintaining a hygienic living environment also reduces the risk.

 

Common Genetic & Metabolic Dog Diseases – Causes, Symptoms, & Prevention

 

• Gastric Dilatation-Volvulus (Bloat) – A Genetic Condition

Gastric Dilatation-Volvulus (Bloat) is a life-threatening illness where the stomach fills with gas and twists, cutting off blood flow. This blockage stops food, liquid, and gas from escaping, resulting in rapid swelling and organ damage.

 

Dogs suffering from bloat exhibit symptoms, including a swollen and firm belly, excessive drooling, restlessness, and unsuccessful attempts to vomit (dry heaving). As the condition worsens, they may struggle to breathe, collapse, or show signs of extreme distress.

 

Preventing bloat involves feeding dogs smaller, more frequent meals instead of one large serving. Avoiding stress during mealtime and providing a calm feeding environment can also lower the risk.

 

• Pancreatitis – A Metabolic Disorder

   

Pancreatitis develops in dogs because of an inflamed pancreas. The root cause of inflamed pancreas is a high-fat diet, obesity, or genetic predisposition.

 

When the pancreas becomes irritated, it releases digestive enzymes prematurely, leading to tissue damage and severe inflammation. This can cause intense abdominal pain, vomiting, diarrhea, fever, and loss of appetite. Affected dogs may also show signs of lethargy and dehydration, refusing food and becoming visibly uncomfortable.

 

Preventing pancreatitis starts with a low-fat diet and avoiding fatty scraps or human food. Feeding a balanced, veterinarian-approved diet and maintaining a healthy weight reduces the risk of pancreatitis.

 

• Diabetes Mellitus – A Metabolic Disorder

 

Diabetes Mellitus happens when a dog’s body fails to produce enough insulin, leading to dangerously high blood sugar levels. This condition affects middle-aged and older dogs, especially those that have higher weight or have a genetic predisposition. Poor diet and lack of exercise can also contribute to insulin resistance, making it harder for the body to regulate glucose levels.

 

Dogs with diabetes show signs such as excessive thirst, frequent urination, unexplained weight loss, and increased appetite. If left untreated, diabetes can cause cataracts, nerve damage, and organ failure.

 

Preventing diabetes starts with maintaining a healthy weight through regular exercise and a controlled diet. Feeding a balanced, high-fiber, low-fat diet helps regulate blood sugar levels, reducing the risk of insulin resistance. Early detection and management, including proper nutrition and insulin therapy when needed, can help diabetic dogs live long, healthy lives.

 

• Hypothyroidism – A Metabolic Disorder

   

In Hypothyroidism, the thyroid gland fails to produce enough hormones, leading to a slowed metabolism. This condition is most common in breeds like Golden Retrievers, Dobermans, and Cocker Spaniels, though it can affect any dog.

 

Dogs with hypothyroidism often experience unexplained weight gain despite no increase in appetite, thinning hair, dry and flaky skin, lethargy, intolerance to cold, and recurring skin infections. Since the disease develops gradually, symptoms may go unnoticed until they become severe.

 

While there is no direct way to prevent hypothyroidism, early diagnosis through regular veterinary check-ups allows for effective management. Once diagnosed, treatment typically involves lifelong thyroid hormone replacement therapy to regulate metabolism and restore normal body functions.

 

• Cushing’s Disease (Hyperadrenocorticism) – A Metabolic Disorder

   

Cushing’s disease, or hyperadrenocorticism, occurs when a dog’s body produces excessive cortisol due to tumors in the adrenal or pituitary glands. This hormonal imbalance affects metabolism, immune function, and overall health.

 

Affected dogs show signs of excessive thirst, frequent urination, unexplained hair loss, a pot-bellied appearance, recurring skin infections, and lethargy.

 

While there is no proven way to prevent Cushing’s disease, routine veterinary check-ups and early blood tests can detect hormonal imbalances before symptoms become severe.

 

• Addison’s disease (Hypoadrenocorticism) – A Metabolic Disorder
  
  

Addison’s disease is an autoimmune condition that damages the adrenal glands. It can also be triggered by infections, cancer, or long-term steroid use. In Addison ’s disease, the adrenal glands fail to produce enough hormones, primarily cortisol and aldosterone. These hormones regulate metabolism, blood pressure, and stress responses.

 

Dogs with Addison’s disease may exhibit vague and intermittent symptoms, making diagnosis challenging. Common signs include lethargy, vomiting, diarrhea, weight loss, increased thirst, and frequent urination. Some dogs experience episodes of weakness or collapse, often mistaken for other health conditions. In severe cases, an Addisonian crisis can occur, causing sudden shock, dangerously low blood pressure, and organ failure, requiring immediate emergency treatment.

 

Preventing Addison’s disease is difficult since its exact cause is not always identifiable. However, routine veterinary check-ups and early screening in at-risk breeds can help detect hormonal imbalances before they become life-threatening. While there is no cure, dogs with Addison’s disease can lead normal lives with lifelong hormone replacement therapy, such as prednisone and fludrocortisone, and routine blood monitoring to keep hormone levels stable.

 

• Polycystic Kidney Disease (PKD) – A Genetic Disorder

   

Polycystic Kidney Disease (PKD) is a genetic disorder that causes fluid-filled cysts to develop in the kidneys, gradually impairing their function. Over time, the cysts enlarge, replacing healthy kidney tissue and leading to progressive kidney failure.

 

Dogs with PKD may not show noticeable symptoms in the early stages, but as the cysts grow and disrupt kidney function, signs of kidney disease begin to appear. Affected dogs may experience increased thirst, frequent urination, weight loss, lethargy, vomiting, and decreased appetite. In severe cases, high blood pressure and a swollen abdomen due to enlarged kidneys may also develop. As kidney function declines, toxins build up in the bloodstream, leading to further complications such as bad breath, ulcers, and neurological issues.

 

Preventing PKD starts with responsible breeding practices. Since the condition is inherited, dogs diagnosed with PKD should not be bred to prevent passing the mutation to future generations. Routine screening through genetic testing and ultrasound imaging can help detect the disease early, especially in at-risk breeds. Although there is no cure, a kidney-supportive diet and hydration management can slow disease progression and improve a dog’s quality of life.

 

• Progressive Retinal Atrophy (PRA) – A Genetic Disease

   

Progressive Retinal Atrophy (PRA) is an inherited eye disease that gradually leads to blindness in dogs. In this disease, the retina’s photoreceptor cells deteriorate over time, preventing the eye from processing light properly. This condition is not caused by infections or environmental factors but is primarily genetic and affects many breeds.

 

Dogs with PRA experience gradual vision loss, starting with night blindness. In the early stages, they may hesitate in dim lighting or struggle to navigate dark spaces. As the disease progresses, vision impairment worsens, leading to difficulty recognizing familiar surroundings, bumping into objects, dilated pupils, and a glassy or cloudy eye appearance. Because PRA is painless, many dogs adapt well to vision loss, but they may become more anxious or hesitant in new environments.

 

There is no cure for PRA, but responsible breeding practices can prevent its spread. Genetic testing helps breeders identify carriers and avoid passing the defective gene to future generations. While PRA itself is irreversible, antioxidants and omega-3 supplements may support overall eye health and slow retinal degeneration.

 

Final Words!

 

Caring for a dog means staying aware of common diseases that can affect their health. Many illnesses start with subtle symptoms that worsen without treatment. However, regular check-ups, vaccinations, parasite control, and a balanced diet help prevent serious conditions. In addition, early detection can help dealing with these common dog diseases, reducing pain and complications. Remember, dogs rely on their owners to notice changes in their behavior, appetite, or energy levels. Quick action can save their lives and improve their health.

 

Your dog’s health depends on your knowledge and proactive care. Share this guide about 26 common dog diseases with other dog owners to spread awareness. If you’ve dealt with a dog illness before, share your experience in the comments. Stay informed, keep your dog healthy, and always prioritize timely veterinary care.