Why Vaccines are Important – Dog Edition

• Core vs. Non-Core Vaccines
• Canine Distemper
• Adenovirus Type 1
• Adenovirus Type 2
• Canine Parvovirus
• Canine Parainfluenza
• Canine Coronavirus
• Canine Rabies
• Canine Bordetella
• Canine Leptospirosis
• Canine Influenza

You bring your dog to the veterinarian’s office and learn which vaccines are due. After the doctor completes a thorough exam, gives your dog a quick jab or two, and makes sure all your questions are answered, you’re visit is finished and you’re on your way. But just what are all those abbreviations on your invoice, such as DA2PPC? And, for that matter, what are those diseases you’re protecting your pet against?

The vaccines your veterinarian recommends are a combination of “core” and “non-core.” The non-core vaccines your pet gets may be different from the ones your friend’s pet in, say, Minnesota gets. That’s because doctors recommend vaccines based on the risk of a certain disease in a geographical area, your pet’s activities and lifestyle, and any underlying health conditions.

For example, a strictly indoor cat may not need all the vaccines an outdoor cat would need. And a dog that competes in agility or other types of activities, where they are around a lot of dogs, may need additional vaccines—more than another dog that never leaves their home. (Stay tuned for the cat edition of this blog!)

Core vs. Non-Core Vaccines

So, what are the differences between core and non-core vaccines? How often do pets need these vaccines? What are the symptoms of each disease we’re vaccinating against, and how could a pet contract them? Simply put, a core vaccine is one that’s considered vital to the health of your pet based on the risk of exposure, how severe the disease is and its mortality rate, and whether it can be transmitted to humans.

Non-core vaccines protect against illnesses that are considered less life-threatening than those covered by core vaccines. They are given depending on your pet’s exposure risk. Because these factors can change over time, it’s good to discuss with your veterinarian any changes to your pet’s lifestyle at each wellness visit.

Note that, just like with human vaccines, no vaccines protect 100% of pets 100% of the time, as there are many different strains of diseases. But vaccines are still very highly effective and offer the best protection for your pet. Further, having a low occurrence of a certain disease, such as parvovirus, in your area doesn’t necessarily mean that the disease is rare and your pet doesn’t need to be vaccinated. It more likely means that most dogs in the area are vaccinated and therefore are much less likely to contract it. In other words, the vaccines are doing their job in those vaccinated pets.

For dogs, core vaccines include:

Canine Distemper (the “D” in DA2PPC)

This vaccine is given to puppies in a series of boosters about 3 weeks apart. Then, as adults, they get boosters as recommended by their veterinarian. Canine distemper is a deadly airborne virus that can affect dogs of all ages. It is found in various types of wildlife, including foxes, wolves, coyotes, and raccoons. Since coyotes and raccoons are found in our local area, distemper is of particular concern. Ferrets are also at risk, so ferrets that share a home with dogs should also be vaccinated.

Spread through sneezing or coughing–or transmitted by sharing food and water bowls, toys, or kennel space–it attacks the respiratory, gastrointestinal, and nervous systems and may cause permanent brain damage in survivors. Infected dogs may shed the virus for months even while displaying no symptoms, and it can be spread from mother to unborn puppy.

The first sign of illness may be watery eyes or even a white to green eye discharge. Nasal discharge, coughing, fever, lethargy, reduced appetite, vomiting, and diarrhea may follow. As the disease progresses, the virus attacks the nervous system and dogs may develop a head tilt, muscle twitches, chewing movements with the jaw along with excessive salivation, turning in circles, seizures, and paralysis to varying degrees. The paw pads may also become thick, hard, and crusty.

Diagnosis is made by observing symptoms and laboratory testing. No drug can kill the virus, so treatment involves supportive care to manage symptoms and prevent secondary infections such as pneumonia. Hospitalization may be needed to administer oxygen and intravenous fluids. Infected dogs must be isolated to minimize the spread of infection. Adult dogs have a higher chance of recovery than puppies but may live with debilitating nervous system issues.

To avoid contracting distemper, ensure that all dogs are fully vaccinated. For young puppies and those that your veterinarian has advised against vaccinating (such as those that are immune compromised), avoid contact with infected animals and wildlife, as a sneeze can spread the virus up to 25 feet. Wait until at least 3 weeks after your puppy has completed their boosters to join obedience classes, doggy daycare, or to be near other dogs, such as at the groomer.

Adenovirus Type 1

This is also known as canine hepatitis. In puppies, this vaccine is given in a series of boosters about every 3 weeks, then adults get boosters as recommended by their veterinarian. Spread through an infected dog’s saliva (through direct contact or airborne droplets sprayed via cough or sneeze), urine, and feces, canine hepatitis causes upper respiratory infections. It goes on to target the kidneys, liver, and eyes and can lead to severe liver damage and death. The fatality rate can be as high as 30 percent.

In recovered dogs, the virus can continue to shed through the urine for over 6 months. In some dogs, chronic hepatitis can occur, as well as blindness.

The virus can be transmitted through asymptomatic dogs and can live on contaminated surfaces for many months. So, while it can help to avoid areas where other dogs have been (such as parks, boarding facilities, and dog shows) unless your dog is never in contact with another dog and every object your dog comes into contact with has been disinfected, there is still a risk of contracting hepatitis. That is why this is a core vaccine.

Symptoms can range from mild to severe and include fever, lethargy, nasal and/or eye discharge, cloudy or blue-tinged eyes, cough, loss of appetite, vomiting, diarrhea, convulsions, and paralysis. It is not contagious to humans.

There is no cure for hepatitis, so treatment is focused on managing symptoms and preventing secondary infections until the dog’s body can fight off the virus and recover. Treatment may include intravenous fluids, antibiotics to fight bacterial infections, and pain medication.

Adenovirus Type 2 (the “A2” in DA2PPC)

This is a form of kennel cough. Puppies receive a series of boosters between 6 and 16 weeks of age about every 3 weeks, then adults get boosters as recommended by their veterinarian. This virus is spread through coughs and sneezes.

It’s important to note that the term “kennel cough” is a rather broad term that encompasses many types of upper respiratory infections. This is much the same as when we say, “I have a cold,” which could be one of more than 200 types of viruses.

Symptoms include fever, and cough—both dry and accompanied by white foam—retching, gagging, and lethargy. A dog may not show symptoms until 3-10 days after exposure, which is why it’s easily contracted from infected dogs not yet showing symptoms at kennels, groomers, dog shows, and parks.

While this virus can be self-limiting and resolve on its own without treatment, it can at times lead to pneumonia, particularly in puppies. Treatment for moderate to severe cases of kennel cough includes managing symptoms and supportive care. Vaccination against adenovirus 2 also cross-protects against adenovirus 1, so it is considered a core vaccine.

Canine Parvovirus (the first “P” in DA2PPC)

In puppies, this vaccine is given in a series of boosters about 3 weeks apart then adults get boosters as recommended by their veterinarian. Parvovirus or “parvo” is usually fatal if left untreated and is highly contagious. It affects the gastrointestinal tract, resulting in fever or low body temperature, abdominal pain, loss of appetite, severe vomiting and bloody diarrhea, dehydration, and even septic shock.

Diagnosis is obtained through fecal testing. Treatment involves intensive care to manage symptoms and prevent secondary infections until the dog’s body can fight off the virus and recover. The infected dog should be kept isolated.

No drug exists that can kill parvovirus; even killing the virus in the environment requires meticulous disinfecting methods. Along with being spread directly from dog-to-dog contact, any contact with contaminated feces, food, and water bowls, toys, leashes, collars, clothing, shoes, hands, or paws can transmit this virus. It’s resistant to the weather as well, which means that it can live in grass and dirt for many months–some say years. A walk through a park can result in you picking up parvo on your shoes and bringing it home to your dog.

Canine Parainfluenza (the second “P” in DA2PPC)

In puppies, this vaccine is given in a series of boosters about 3 weeks apart then adults get boosters as recommended by their veterinarian. While it is not a core vaccine, it’s included in DA2PPC because this respiratory virus is highly contagious and has no treatment available other than managing symptoms and secondary infections.

Parainfluenza is not the same as canine influenza but, rather, is a form of kennel cough. Symptoms include fever, loss of appetite, lethargy, coughing, wheezing, sneezing, and mucus discharge. It’s passed both through dog-to-dog contact and from being near an infected dog in an environment such as boarding facilities, grooming salons, dog shows, and dog parks.

Canine Coronavirus (the “C” in DA2PPC)

This vaccine is given to puppies in a series of boosters about 3 weeks apart, and then adults get boosters as recommended by their veterinarian. Canine coronavirus is not the same virus that causes COVID-19 in humans and is not contagious to humans. It’s not a core vaccine but is included in DA2PPC because this intestinal virus is highly contagious and causes dogs considerable discomfort.

There is no treatment for the virus itself, so managing symptoms such as diarrhea (which may contain blood or mucus), nausea, vomiting, and dehydration can help keep an infected dog comfortable and prevent secondary infections. Symptoms may also include lethargy and loss of appetite.

Canine coronavirus is spread through direct contact with oral fluids, sharing food or water bowls, or contact with an infected dog’s feces. Once a dog is infected it can take anywhere from 1 to 4 days for symptoms to appear. Recovered dogs can carry the disease for up to six months.

Canine Rabies

This core vaccine is administered in one dose and can be given as early as 3 months of age, depending on the state in which you live. In Florida, the minimum age is 4 months. Boosters can be every 1 year or 3 years, depending on the vaccine given. Rabies is fatal to dogs—with no treatment available—so prevention is vital. Rabies is transmissible to humans.

Rabies is transmitted through the bite of an infected animal to another, although sometimes rabies is passed through a scratch of an infected animal. Rabies affects the central nervous system, including the spinal cord and brain. Symptoms include increased appetite, sudden personality change, fever, aggression, excessive drooling (or foaming), difficulty swallowing, staggering, seizures, and paralysis.

Clinical diagnosis of rabies is only possible through a biopsy of brain tissue after death. Treatment depends on when the pet is brought to the vet. If your dog has been bitten by a wild animal, it’s important to contact your vet immediately, as a booster of the rabies vaccine may be given to lessen the chance that your dog will contract the virus.

The vet will also clean the wound to prevent infection. It is possible to contract rabies through your dog’s wound, so disposable gloves are necessary when handling. The incubation of the virus can be days or months before signs develop, in which case it is too late to treat.

Canine Bordetella

This vaccine can be given in one intranasal dose for both puppies and adults. Veterinarians usually recommend most adult dogs receive a bordetella vaccine every six months.

This is a non-core vaccine, but this variant of kennel cough is highly contagious, passing easily from dog to dog in environments such as dog parks, boarding facilities, grooming salons, and dog shows. It’s spread both through infected respiratory droplets and through sharing toys, dog bowls, and the same kennel area.

Symptoms include coughing, sneezing, nasal discharge, fever, lethargy, and loss of appetite. As with all viruses, there is no medication available for treatment, so managing symptoms and preventing secondary infections can help keep an infected dog more comfortable.

Canine Leptospirosis

In puppies and adults, this non-core vaccine can be given in 2 boosters 2-4 weeks apart, then adults get boosters as recommended by their veterinarian. Leptospirosis mainly occurs in areas with high rainfall in wet environments where standing water can harbor the bacteria and lead to infection. Swimming in or drinking infected water in lakes, ponds, and puddles—or walking through infected water, soil, or mud—puts dogs at risk. Contact with rodents can also spread this bacterial infection.

The bacteria enter a dog’s body through its mucous membranes or wounds, even something small such as a cut or scrape. The bacteria then burrow into the pet’s skin and spread through the bloodstream. Infection can also occur through a bite from an infected animal, by eating an infected animal, or through sharing food or water bowls with an infected animal. It can be a serious, life-threatening disease. It can also be transmitted to other pets and humans.

Symptoms range from none at all to fever, muscle stiffness, lethargy, loss of appetite, increased thirst and urination, vomiting, diarrhea, jaundice, difficulty breathing, cough, and nasal discharge. As leptospirosis travels through the bloodstream, the dog’s liver, kidneys, and other organs can be affected. Severe liver or kidney failure can lead to death.

Diagnosis is made through the presence of bacteria in blood and urine samples. Some dogs with mild cases can recover on their own, but for those that develop severe illness, treatment includes antibiotics and the administration of IV fluids, along with possible hospitalization. When treated early, the chances for recovery are good, although permanent kidney or liver damage may still occur even with aggressive treatment.

Home care includes restricting the dog to a crate so it can get adequate rest and recover. The dog should be kept away from other pets and people, especially children. Also, medical-grade gloves should be worn when handling the dog and his or her waste. Any areas that have been in contact with the dog’s bodily fluids should be disinfected with a bleach solution. Leptospirosis can be shed through the urine for many weeks after infection.

To prevent your dog from contracting leptospirosis–along with vaccinating–ensure your dog avoids rodent droppings and urine, and possible water sources contaminated with leptospirosis.

Canine Influenza

Puppies can receive their first dose of this vaccine as early as 6-8 weeks, with a second dose about 3 weeks later. Adults receive 2 doses, 2-4 weeks apart. Annual boosters are given at your veterinarian’s recommendation. This is a non-core vaccine for a highly contagious virus. Humans cannot get canine influenza. Unlike a human “flu season,” canine influenza is a threat all year round.

Symptoms include fever, lethargy, decreased appetite, cough, and nasal and eye discharge. Canine influenza is transmitted in many ways. Respiratory droplets aspirated from an infected dog through coughing, sneezing, and barking can infect healthy dogs, as can sharing food and water bowls.

The virus can live on surfaces for up to 48 hours, so crates, kennel surfaces, collars, leashes, toys, etc. should be thoroughly disinfected. The virus can live on clothing for 24 hours and on human hands for 12 hours, so people can also facilitate the spread of the virus.

The vast majority of dogs exposed to canine influenza contract the virus; an asymptomatic dog can spread it to others. The incubation period for the virus, in which it is possible to spread it to others, is 3-4 days from exposure and 7-10 days after recovery. Most dogs take 2-3 weeks to recover. Quarantine from other pets is recommended.

Diagnosis is often made through a PCR test from a nasal swab, much the same way humans are tested for COVID-19. There is no medication available for this virus, so supportive care and managing secondary infections, such as pneumonia, are used until the dog’s immune system can recover. Puppies, older dogs, and immune-compromised dogs are most at risk for complications that could lead to death.

We hope this blog has answered any questions you may have about the vaccines that your veterinarian recommends. Be sure to read the Cat Edition of this blog post Cat Edition of this blog post, too! Working together, you and your vet can help your pets live longer, healthier, happier lives.