veterinarian drawing up vaccines out of a brown glass bottle
Protecting your pets from deadly diseases doesn’t have to be hard. Vaccinating your pet provides the best chances for a happy, healthy life.


Whether you buy a purebred puppy from a breeder or adopt a senior pet from a shelter, keeping them up-to-date on their vaccinations is critical to the overall health of your animal. Protecting your pet against the common infectious and parasitic diseases ensures you have your four-legged friend for as long as possible. Knowing which diseases we vaccinate your pet against, and understanding the importance of why you shouldn’t let those pet vaccines expire, will ensure you provide the best possible life for your furry friend.

But…what’s with all the vaccines?

The American Veterinary Medical Association (AVMA) has established a list of select vaccinations that they feel are essential for the health of your pet. These essential vaccines, or core vaccines, are typically administered in a “series”. This means bringing your pet in for several injections at specific intervals, usually 3-4 weeks apart, before protection is achieved. Although these vaccinations can be given individually, today most practices will use combination vaccines in an effort to assist the pet owner. This reduces the number of injections your pet receives during their first years. You can expect your pet’s first few veterinary appointments to contain vaccinations against several possible diseases such as rabies, bordetella, Lyme disease, canine influenza, and distemper, among others.

The “distemper” vaccine, considered a core vaccine for all dogs in the United States, is a perfect example of a combination vaccine. We’re sure you’ve seen “DHLPP” or “DA2PP” on the list of your pet’s vaccines. But did you know it actually protects against a host of other diseases you may not know your dog is susceptible to beyond distemper?

And what does that alphabet soup actually mean?

D = Canine Distemper virus
H = Hepatitis (or A2) – same as A2 (Canine Adenovirus-2)
A2 = Canine Adenovirus-2 (or H)
P = Parvovirus

P = Parainfluenza
L = Leptospirosis

The exact combination of your dog’s distemper combo vaccine often varies from manufacturer to manufacturer but the most important diseases it protects against are canine distemper, canine adenovirus-2 infection (hepatitis and respiratory disease), canine parvovirus infection, and parainfluenza.

What exactly does all that mean?

The Core Vaccines

Canine Distemper (CVD)

Canine distemper, is a contagious disease caused by the canine distemper virus (CDV). The distemper virus works by attacking the respiratory, gastrointestinal, and neurologic systems of dogs. This highly transmissible virus can also infect ferrets and wild animals, including raccoons, skunks, minks, weasels, foxes, and coyotes. Distemper spreads through airborne exposure, such as sneezing or coughing. The virus also transmits by shared food and water bowls and equipment. Symptoms include discharge from the eyes and/or nose, fever, coughing, vomiting, diarrhea, seizures, twitching, and even paralysis. Unfortunately, canine distemper can also be fatal. Furthermore, the death rate for canine distemper virus can reach 50 percent. Animals that do recover, though, are often left with permanent neurologic disabilities.

Less common today than it was before the first vaccines in the 1960s, distemper is still present in wildlife populations that might have contact with domestic animals. It is shed through all body secretions, as well as hands and feet. An infected dog is capable of shedding the virus for months. Warm, dry, or sunny conditions will kill CDV, but it is resistant to the cold and can survive in near-freezing, shady environments for quite some time.

There is no cure for distemper however the disease is mostly preventable through proper vaccination. Treatment can be expensive and consists of supportive care and efforts to prevent secondary infections, control symptoms of vomiting, seizures and more. If the animal can survive the symptoms, the dog’s immune system will have a better chance to fight it off.

Canine Adenovirus -2 (Canine Hepatitis)

Infectious canine hepatitis, also known as adenovirus, is a highly contagious, viral infection that affects the liver, kidneys, spleen, lungs, and the eyes of the affected dog. This virus is unrelated to the human form of hepatitis. The virus transmits through secretions of the body, namely urine. Canine hepatitis is highly contagious and begins flowing through the blood stream almost immediately upon entrance to the body. Once the virus has enters the bloodstream, it can reach and affect any organ of the body, though the liver seems particularly susceptible.

One of the reasons that this virus is so deadly is because it is highly contagious. In addition to direct contact with urine, it also transmits through the use of contaminated objects, such as food bowls and bedding. Because this virus can live in feces and urine, it can contaminate almost anything that it touches.

Symptoms range from a slight fever and congestion, to vomiting, jaundice, stomach enlargement, and pain around the liver. Many dogs can overcome the mild form of the disease, but the severe form can kill. There is no cure for canine hepatitis, but doctors can treat the symptoms.


Canine parvovirus type 2 (CPV-2) is a common and highly contagious viral disease that can affect any dog, but unvaccinated dogs and puppies less than four months of age are at the most risk to contract it. The virus attacks the gastrointestinal tract and immune system of puppies and dogs, and creates loss of appetite, vomiting, fever, and often severe, bloody diarrhea. It can also attack the hearts of very young puppies.

CPV-2 is highly contagious and spread through direct contact with infected dogs or infected feces. Hands, food dishes, leashes, and shoes can carry it easily. The virus is very stable in the environment and can survive for more than a year in feces and soil. Even in extreme bouts of heat, cold, drought, or humidity. Though 85 percent to 90 percent of treated dogs survive, the disease requires extensive supportive patient care and can be expensive to treat. Extreme dehydration can come on rapidly and kill a dog within 48-to-72 hours, so prompt veterinary attention is crucial. In untreated dogs, the mortality rate can exceed 90 percent.

There is no cure, so keeping the dog hydrated and controlling the secondary symptoms can keep him going until his immune system beats the illness. Vaccination, however, is highly effective.

Canine Parainfluenza

Canine parainfluenza causes mild respiratory disease in dogs and is most commonly responsible for infectious tracheobronchitis, or kennel cough. Kennel cough results from inflammation of the upper airways. Bacterial, viral, or other infections, such as Bordetella, often cause the disease, which usually involves multiple infections simultaneously. Usually, the disease is mild, causing bouts of harsh, dry coughing. Sometimes coughing is severe enough to spur retching and gagging, along with a loss of appetite. In rare cases it can be deadly. It spreads easily between dogs kept close together, which is why it passes quickly through kennels. Antibiotics are usually not necessary, except in severe, chronic cases. Cough suppressants can make a dog more comfortable.

Your pet vaccines may also include additional letters or abbreviated terms that may represent any of the following core vaccine(s):

Rabies (RV)

Rabies is a deadly, viral disease that can attack the central nervous system of many animals. All warm-blooded animals, including wild animals, dogs, cats, and humans, are susceptible. Though the disease is not common, it remains prevalent in wildlife populations, primarily among raccoons, bats, foxes, and skunks, that may have contact with domestic animals. The last reported case of rabies in a human in Illinois was in 1954, however local wild animals do occasional test positive. In fact, rabies was confirmed in bats just a short drive from our fair Shire less a month ago.

The virus can have an incubation period lasting from days to months. It usually transmits through contact with the saliva of an infected animal. An animal’s saliva becomes infective once the virus has traveled through the animal’s nervous system from the initial bite site to the brain and, ultimately, to the salivary glands.

Pets and people usually become infected through a bite wound. Once the virus enters the salivary glands, the animal can pass the infection to other animals or humans through saliva. Rabies invades the central nervous system, causing headache, anxiety, hallucinations, excessive drooling, fear of water, paralysis, and death. Treatment within hours of infection is essential, otherwise, death is highly likely. Once clinical signs appear, rabies is generally fatal, which is why any pet that bites a human and has an unknown or out-of-date rabies vaccination status may be subject to quarantine or even euthanasia, depending on state laws. Most states require rabies vaccination. Check with your vet about rabies vaccination laws in your area.

While considering the above pet vaccines as “Core Vaccines” by the American Veterinary Medical Association (AVMA), they also recommend the following vaccinations:

Bordetella (BORD, BV)

Bordetella bronchiseptica is a bacterium commonly associated with respiratory disease in dogs. It can also infect cats, rabbits, and, in rare cases, humans. It is one of the more common bacterial causes of canine infectious tracheobronchitis, otherwise known as Kennel Cough. Bordetella bronchiseptica is one of several viral and bacterial agents responsible for kennel cough syndrome. Bordetella is highly contagious, easily transmitted through the air or direct contact, and resistant to destruction in the environment.

This highly communicable bacterium causes severe fits of coughing, whooping, vomiting, and, in rare cases, seizures and death. A safe and effective vaccine, available in injectable or nasal spray, for the upper-respiratory infection is available for dogs and cats.

Leptospirosis (LEPTO)

Leptospirosis is a potentially serious disease caused by the bacterium Leptospira interrogans. Since leptospirosis is bacterial, some dogs may show no symptoms at all. The organism spreads through infected urine, but exposure to contaminated water or soil, reproductive secretions, and even consumption of infected tissues can also transmit the infection. Introduction of the organism through skin wounds can also occur. Carriers of the organism include raccoons, opossums, rodents, skunks, and dogs.

Leptospirosis is a worldwide, zoonotic disease, meaning it spreads from animals to people. The bacteria can survive for long periods of time in water and is found in swamps, streams, lakes, and standing water. The bacteria also survive well in mud and moist soil, and localized outbreaks can occur after heavy flooding.

Once the bacteria infects a dog, the leptospirosis organisms rapidly advance through the bloodstream. When symptoms do appear, they can include fever, vomiting, abdominal pain, diarrhea, loss of appetite, severe weakness and lethargy, stiffness, jaundice, muscle pain, and infertility. Antibiotics are effective if given quickly. Because the organism settles in the kidneys and actually reproduces there, inflammation and even kidney failure may develop. Liver failure is another common consequence of infection.

Lyme Disease (LYME)

Unlike the famous “bull’s-eye” rash that humans exposed to Lyme disease often spot, no such tell-tale symptom occurs in dogs. Lyme disease (or borreliosis) is an infectious, tick-borne disease caused by a type of bacteria called a spirochete. Transmitted via ticks, an infected dog often starts limping, his lymph nodes swell, his temperature rises, and he stops eating. The disease can affect his heart, kidney, and joints, among other things, or lead to neurological disorders if left untreated. If diagnosed quickly, a course of antibiotics is extremely helpful, though relapses can occur months or even years later.

Canine Influenza (CIV, H3N8, H3N2)

This new, highly transmissible virus was first detected in 2004 among a group of racing greyhounds in Florida. The canine influenza H3N8 strain, investigators eventually learned, developed when an equine influenza virus adapted to infect dogs. This represented a rare event, because the new virus was canine specific (only transmissible to other dogs). However, in 2015 Dr. Kathy Kurth at the University of Wisconsin discovered that the sick dogs in the Chicago area were actually infected with H3N2 — a strain that, according to VetStreet, had previously been seen only in Korea and parts of China.

Canine influenza has caused localized disease outbreaks around the United States and has been reported in more than 40 states plus the District of Columbia. It’s spread between dogs through direct contact (coughing, sneezing, facial licking) or indirect contact (contaminated bowls, leashes, collars, or the hands or clothing of people who handle ill dogs).
The bad news: Virtually all dogs exposed to CIV become infected; however, 20 percent of dogs don’t show signs but can still spread the virus.
The good news: There is a pretty effective vaccination against both strains. Also, on the bright side, canine influenza does not infect people, and, so far, there’s no documentation that cats have become infected by exposure to infected dogs.

We read about so many different illnesses, and so many different vaccinations and vaccination combinations, that it can often times be pretty confusing to know which vaccines are needed vs which ones can wait – or even if they are needed at all!

The invention of the internet has led to a great many wonders in our time, however the accuracy of medical information online still leaves much to be desired. With so many sources of information on pet vaccines, it can be overwhelming when Dr. Google, or even your breeder, disagrees with the information you have gotten from your veterinarian. Knowing and understanding what the common vaccines are, what they cover, and how they protect your pet is crucial in being able to make appropriate medical decisions regarding your animal’s health.

Of course, your veterinarian should weigh in and can always provide more information and guidance if necessary. Sitting down with your vet and plainly discussing your concerns and your lifestyle, can help them determine if your pet needs more than just the basic inoculations.

Still have questions? Check out When to Vaccinate Your Dog: A Guide