Dog Zoonotic Diseases

For generations, dogs have been referred to as "man's best friend," and for a good reason. They're loyal, loving, and make great companions.

Due to this fact, people tend to keep them in close contact, including in their homes.

While this is typically a good thing, it does come with some risks – namely, the potential to transmit diseases from dogs to humans. These are known as zoonotic diseases; unfortunately, dog owners must be aware of a few.

In this article, we'll take a look at some of the most common zoonotic diseases of dogs, what signs and symptoms to look out for, and how to prevent them.

What are zoonotic diseases?

Before we get into specific diseases, it's important to understand what zoonotic diseases are.

Zoonotic diseases are illnesses that can be transmitted from animals to humans. Zoonotic diseases are also known as Zoonoses.

According to the same source, viruses, bacteria, fungus, and parasites can cause various disorders ranging from mild and scarcely apparent to severe and even life-threatening.

Over 250 zoonoses can be transmitted from animals to humans, with less than 40 involved in cats and dogs.

There are several ways that zoonoses can be transmitted from animals to humans. The most common is direct contact, which can occur when people touch an infected animal or come in contact with their saliva, urine, or feces.

Zoonoses can also be transmitted indirectly through contaminated soil, water, or food. Insects can also spread some diseases, either by biting an infected animal and then biting a human or by coming into contact with the animal's blood and then a human.

What are the reservoirs of zoonoses?

The reservoirs of zoonoses are the animals infected with the disease and can transmit it to humans. Any animal can be a reservoir for zoonoses, but some are more common than others.

The most common reservoirs for zoonoses are:

• Domestic animals like cats, dogs, and rabbits
• Wild animals like bats, raccoons, and rodents
• Farm animals like cattle, pigs, ducks, chickens, and sheep
• Insects like fleas, ticks, mites, and mosquitoes

The CDC advises that people take extra precautions when handling wild or farm animals, as these are more likely to be reservoirs for zoonoses.

Why should we care about dogs specifically?

While any animal can be a reservoir for zoonoses, dogs are particularly important to consider because of how close they tend to be kept to humans.

According to the statistics on the number of dogs in the United States from 2000 to 2017 on Statistica, people owned approximately 89.7 million dogs in the United States in 2017. The American Kennel Club states that this number drastically increased to 54% due to the Covid-19 pandemic.

If we assume there are only 89.7 million dogs. If we compare the number with the total human population in the United States, which is 328 million in 2019 according to the U.S. Census Bureau, it would mean that approximately 27% of households in the United States have at least one dog.

This figure is much higher when the CDC reports that 63 percent of U.S. homes have at least one pet. This close contact between dogs and humans means a more significant potential for the transmission of zoonoses.

Further, the statistics;

• Annually, almost 5 million people in the United States suffer a dog bite.
• Infection happens in 15% of dog bite wounds.

What this means is that not only is there a potential for dogs to transmit zoonoses to humans, but also that dog bites are a common source of infection.

This is why it's important to be aware of the risks of zoonoses and take precautions to prevent them.

The most common dog zoonoses

There are a number of different zoonoses that can be transmitted from dogs to humans, but some are more common than others.

The most common zoonoses transmitted from dogs to humans are:

Viral infections

Rabies

Rabies is a life-threatening virus transmitted through infected animals' saliva, usually through a bite. Rabies targets the neurological system, causing paralysis, seizures, and even death.

While rabies is rare in the United States, it is still a risk. According to the CDC, there were only three reported cases of human rabies in the United States in 2015, but this is likely because most people exposed to rabies get vaccinated.

However, rabies is much more common in other parts of the world. The World Health Organization (WHO) estimates that there were only three reported cases of human rabies in the United States in 2015.

The best way to protect yourself from rabies is to get vaccinated and to avoid contact with animals that may be infected.

If an animal bites you, it's important to clean the wound and see a doctor as soon as possible, as you may need a series of rabies shots.

Noroviruses

Noroviruses are a type of virus that causes vomiting and diarrhea. They're often called "stomach flu" or "food poisoning."

Noroviruses are one of the most common causes of gastroenteritis (stomach flu) in the United States. According to the CDC, noroviruses globally cause 685 million cases of gastroenteritis each year.

Noroviruses are usually transmitted through contaminated food or water, but they can also be transmitted through contact with an infected person or an infected animal like a dog.

Bacterial infections

Pasteurella

Pasteurella is a type of bacteria that can cause an infection if you're bitten or scratched by an animal, particularly a cat or a dog.

Symptoms of a Pasteurella infection include redness, swelling, pain at the site of the wound, fever, headache, and nausea.

If the Pasteurella is left untreated, it can spread to other parts of the body and cause more serious problems like pneumonia or meningitis.

Pasteurella infections are usually treated with antibiotics.

Salmonella

Salmonella is a type of bacteria that can cause food poisoning. Bacteria Salmonella is usually transmitted through contaminated food but can also be transmitted through contact with infected pets.

Salmonella poisoning symptoms include diarrhea, fever, and stomach pains. 

In severe cases, salmonella can lead to more serious problems like dehydration, septicemia (blood poisoning), and meningitis.

Salmonella infections are usually treated with antibiotics, but severe cases may require hospitalization.

Brucella

Brucella is a type of bacteria that can cause an infectious disease called brucellosis. It's generally spread through contact with infected animals but may also be transmitted via contaminated food or water.

According to the CDC, signs and symptoms of brucellosis include fever, sweats, headaches, muscle pain, and fatigue. These symptoms can persist for several weeks or even months.

Brucellosis is a serious illness that, if left untreated, can be fatal. Antibiotics and rest are typically used in treatment.

Yersinia enterocolitica

Yersinia enterocolitica is a gram-negative bacteria that can cause an infection called yersiniosis. This zoonosis is usually transmitted through infected birds, pigs, deer, and cattle but can also be transmitted from dogs.

The main symptom of yersiniosis is severe diarrhea that may contain blood and pus. Other symptoms include abdominal pain, fever, and nausea.

Yersiniosis is treated with antibiotics.

Campylobacteriosis

Campylobacteriosis is a zoonose caused by the bacterium Campylobacter. This disease is usually transmitted through direct contact with infected animals and through contaminated food or water.

Campylobacteriosis symptoms include diarrhea, cramps, stomach pain, and fever. More than 50 percent of infected patients suffer from bloody diarrhea. These symptoms often last between two and five days.

Campylobacteriosis is usually treated with antibiotics.

Capnocytophaga

Capnocytophaga canimorsus is a species of bacteria found in dog and cat mouths. While most people who are exposed to this bacteria do not become ill, it can cause a severe infection in persons who have compromised immune systems.

Symptoms of a Capnocytophaga infection include fever, chills, diarrhea, nausea, vomiting, swollen lymph nodes, and abdominal pain. These symptoms can lead to sepsis, which is a life-threatening condition.

Capnocytophaga infections are treated with antibiotics. People with severe infections may need to be hospitalized.

Leptospirosis

Leptospirosis is a zoonose caused by the bacterium Leptospira. It's usually transmitted through contact with infected animals and through contaminated water or soil. Leptospirosis in humans is referred to as Weil's disease.

Symptoms of leptospirosis include fever, chills, headache, muscle pain, swollen lymph nodes, and nausea. 

Leptospirosis is treated with antibiotics. In severe cases, hospitalization may be necessary.

Bordetella bronchiseptica

Bordetella bronchiseptica is a bacterial infection that can cause kennel cough. It's usually transmitted through contact with infected dogs but can also be transmitted through the air. However, human infections are rare.

Kennel's cough signs and symptoms include a dry, hacking cough, fever, and a runny nose. These symptoms usually last for two to three weeks.

Kennel cough is usually treated with antibiotics. In severe cases, hospitalization may be necessary.

Coxiella burnetii

Coxiella burnetii is a type of bacteria that can cause an infection called Q fever. It's usually transmitted through air and direct contact with infected animals but can also be transmitted through contaminated food or water.

Symptoms of Q fever include fever, chills, headache, muscle pain, and nausea. 

Q fever is treated with antibiotics. In severe cases, hospitalization may be necessary.

Staphylococcus intermedius

Staphylococcus intermedius is a type of bacteria that can cause an infection called staphylococcal dermatitis. It's usually transmitted through direct contact with infected animals but can also be transmitted through the air.

Symptoms of staphylococcal dermatitis include red, inflamed skin, hair loss, and crusting. 

Staphylococcal dermatitis is treated with antibiotics. In severe cases, hospitalization may be necessary.

Methicillin-resistant staphylococcus aureus (MRSA)

Methicillin-resistant staphylococcus aureus (MRSA) is a type of bacteria that can cause fatal infections in humans. It's usually transmitted through direct contact with infected animals. This zoonose is usually seen in domestic animals like pigs, horses, cattle, cats, and dogs.

According to NLH, immunocompromised patients are more susceptible to MRSA infections. The symptoms of MRSA depend on the location of the infection. Skin infections usually cause redness, swelling, and pus. Lung infections can cause coughing, chest pain, and difficulty breathing. 

Bloodstream infections can cause fever, chills, and low blood pressure.

MRSA is treated with antibiotics. In severe cases, hospitalization may be necessary.

Vector-borne zoonoses (parasitic infections)

Sarcoptes (Scabies/Sarcoptic Mange )

Sarcoptes are a type of mite that can cause an infection called scabies. It is commonly known as sarcoptic mange. It usually infects humans through skin contact with infected animals but can also be transmitted through contaminated bedding or clothing.

Symptoms of scabies include itching, redness, scaly skin, and loss of hair. Sarcoptic mange is highly contagious.

Scabies is treated with topical medications. In severe cases, hospitalization may be necessary.

Toxocara (roundworm)

Toxocara is a type of parasitic worm that can cause an infection called toxocariasis. It's usually transmitted through contact with contaminated water, soil, or sand.

Symptoms of toxocariasis include fatigue, abdominal pain, and coughing. 

Toxocariasis is treated with antiparasitic medications. In severe cases, hospitalization may be necessary.

Lyme Disease (lyme borreliosis)

Lyme disease is a bacterial infection spread by the bite of an infected tick. Lyme disease symptoms include fever, chills, headache, muscle pain, and fatigue.

Lyme disease is treated with antibiotics. In rare cases, hospitalization is sometimes required.

Cheyletiella (mites/ walking dandruff)

Cheyletiella is a non-burrowing mite that can cause an infection called cheyletiellosis. It's usually transmitted through direct contact with infected animals and through contaminated bedding or clothing.

Symptoms of cheyletiellosis include itching, redness, skin lesions, and bumps on the skin. 

Cheyletiellosis is treated with topical medications.

Dermatophytosis (ringworm)

Dermatophytosis is a fungal infection that can cause an infection called ringworm. It's usually transmitted through direct contact with infected pets, especially puppies, but can also be transmitted through contaminated bedding or clothing.

Symptoms of ringworm include intense itching, redness, and a ring-shaped rash on the skin. 

Ringworm is treated with antifungal medications.

Ascarids (roundworms/ nematodes)

Ascarids are a type of parasitic worm that can cause an infection called ascariasis. These internal parasites are usually transmitted through contact with a pet's feces.

Symptoms of ascariasis include fatigue, abdominal pain, vomiting, and visible worms in the stools. This highly contagious zoonotic disease can be passed from person to person.

Ascarid infections are treated with antiparasitic medications.

Echinococcosis (tapeworms)

Echinococcosis is a life-threatening condition caused by the tapeworm Echinococcus. This zoonose is transmitted through contact with contaminated water, soil, or food.

Symptoms of echinococcosis include abdominal pain, fever, and weight loss due to the cysts growing in the liver, lungs, or brain.

Echinococcosis is treated with antiparasitic medications and surgery to remove the cysts.

Hookworms 

Hookworms are parasitic worms that can cause an infection known as ancylostomiasis. These intestinal parasites are commonly transmitted through touch with unclean soil or feces.

Symptoms of ancylostomiasis include fatigue, abdominal pain, diarrhea, anemia, and bloody stools. This is a highly contagious zoonotic disease.

Hookworm infections are treated with antiparasitic medications.

Tapeworms 

Tapeworms are parasitic worms that can cause taeniasis. These intestinal parasites are commonly transmitted through contact with contaminated food or water.

Symptoms of taeniasis include abdominal pain, diarrhea, weight loss, and fatigue.

Taeniasis is treated with antiparasitic medications.

Who are at risk?

Usually, healthy people with strong immune systems are not at risk for developing serious illnesses from most zoonoses. However, certain groups of individuals are more vulnerable and should take special care to avoid zoonoses contact. These groups include:

• Pregnant women
• Infants and young children
• Elderly people
• People with a compromised immune system
• People work with animals or animal products

How to prevent zoonoses in your pet dog?

The best way to prevent your pet dog from getting a zoonotic disease is to practice good hygiene. For this:

• After handling the dog, properly wash your hands with soap and water.
• Keep your dog clean and well groomed. (There are tools that ease your work when grooming your dog. Here are The Top Pet Grooming Tools For Dogs.)
• Avoid allowing your dog to lick your face or hands
• Pick up and dispose of your dog's feces properly
• Visit the veterinarian regularly for check-ups and vaccinations
• Keep your dog away from sick animals (For this, you can keep your pet in a dog crate when unattended. We recommend reading The Best Quality Small Dog Crates.)

Additionally, you can train your dog to avoid contact with other animals through dog training. Dogs respond well to dog treats and positive encouragement.

For this, we recommend These Pet Food Express Dog Treats.

Preventative medication and vaccinations for zoonoses in your dog

There is no single vaccine or medication that will protect your dog from all zoonotic diseases. But some medications and vaccinations can help prevent your pet from getting some of the more common zoonotic diseases.

For example, in many states, annual rabies vaccination is required by law and is recommended for all pet owners. This vaccine will protect your dog from the rabies virus, which is a deadly zoonotic disease. Other vaccines may also be used to prevent zoonoses in dogs.

Other vaccines that your vet may recommend:

• Bordetella vaccine to protect against kennel cough
• leptospirosis vaccine to protect against this bacterial disease

Further, you can prevent many parasites by giving your dog regular preventive medication.

For example, using an approved anthelminthic (de-worming) medication on a monthly basis can help prevent your dog from getting tapeworms, hookworms, and roundworms.

Using a tick and flea preventative medication can also help keep your dog from getting parasites.

As always, consult with your veterinarian to see what prevention measures are best for your pet dog.

Handling a zoonotic disease infected dog

When handling an infected animal, you should be aware of the risk factors for zoonotic diseases.

You should:

• After handling the animal, properly wash your hands with soap and water.
• Avoid allowing the animal to bite or lick your face or hands
• Wear gloves when handling the animal
• Disinfect and clean any equipment that came in contact with the animal.

If you happen to handle a rabid animal or a wild animal, you should be extra careful. Immediately report the incident to your local health department or animal control in this case.

If an animal bites you, wash the wound with soap and water and see a doctor as soon as possible.

Conclusion

As you see, many zoonoses can infect dogs. But it doesn't mean you can't have a dog at home. Healthy dogs can be wonderful pets that bring joy to our lives.

Taking several precautions can help prevent your pet dog from getting a zoonotic disease.

And, if you do find yourself dealing with a zoonotic disease, don't panic. There are many ways to treat and prevent these diseases. So, get informed and take the necessary steps to keep you and your pet dog healthy and happy.

FAQ