1. How Vaccines Work
A vaccine contains either a weaken or killed form of a pathogen such as a virus or a bacteria. The vaccination will not cause severe illness but will give the immune system a “practice run” at fighting the disease. The immune system will create antibodies to fight the disease. These antibodies are specific to a particular pathogen; for example, rabies antibodies are only effective against the rabies virus and are not effective against other diseases. A high antibody titre (concentration) will provide the patient with immunity to that specific disease. A low titre or zero titre will not provide immunity.
2. Duration of Immunity
Vaccination schedules are created using the duration of immunity for most patients. The duration of immunity (DOI) is the length of time that the patient will be have sufficient antibodies to be immune to the disease. The 2011 AAHA Canine Vaccination Guidelines provide a vaccination schedule that will ensure that the majority of dogs are vaccinated frequently enough to be immune. However, it is possible for a patient to have a longer or shorter DOI than average. Personalized vaccination schedules for patients can be created using titre testing. A titre test is a bloodtest that measures the antibody concentration for a particular disease (such as distemper or parvo) to determine if the patient is immune to the disease.
3. Vaccine Reactions & Overvaccination
The canine (and feline) vaccinations available on the market today have an excellent safety record. However, adverse events following vaccination (vaccine reactions) are still possible. There are a variety of adverse events associated with vaccination. Adverse events in the days immediately following vaccination can include lethargy, mild fever, loss of appetite, and pain at the injection site. More severe reactions such as anaphylaxis (allergic reaction causing swelling of the face and neck) can also occur. Other adverse events that may be more long term include autoimmune diseases (including immune-mediated hemolytic anemia) and injection site sarcomas (tumours). While severe vaccine reactions are rare, all dog owners are advised to monitor their pets for signs of adverse events.
4. Canine Diseases & Vaccinations
The 2011 American Animal Hospital Association (AAHA) Canine Vaccination Guidelines divides vaccinations into 2 categories: core vaccinations and non core vaccinations. The AAHA Canine Vaccination Guidelines are the standard used throughout most of North America when recommending vaccinations for dogs. The AAHA Guidelines can be found on the AAHA website (see Appendix 2: Resources). It is important to recognize that the AAHA Guidelines are guidelines only: the exact vaccination schedule of a patient will vary depending on medical history (illnesses), missed vaccinations, and lifestyle.
A. Core Vaccinations
Core vaccinations are recommended for all healthy dogs. The core vaccinations as recommended by the AAHA Canine Vaccination Guidelines are rabies virus, canine distemper virus, adenovirus, and parvovirus.
I. Rabies Vaccination
Rabies virus is a fatal disease that is spread from infected animals by biting or scratching. All mammals, including humans, dogs, cats, bats, raccoons, and skunks can be infected by rabies. Once a person or animal becomes infected with rabies there is no treatment. Rabies is fatal. The clinical signs of rabies vary; the symptoms are usually neurological such as weakness, limping, dizziness, changes in behaviour and seizures. Some animals become aggressive while others become lethargic. If you suspect rabies exposure or infection seek medical attention immediately.
Rabies is a core vaccination and is recommended for all dogs. The AAHA Guidelines recommends puppies receive a rabies vaccination no earlier than 12 weeks of age. A single booster should be given 1 year after the puppy vaccination. Subsequent vaccinations should be given every 3 years.
II. Canine DA2PPv Vaccination
A canine DA2PPv vaccination provides inoculation against 4 viruses: Canine Distemper Virus, Canine Adenovirus Type 1 and Type 2, Canine Parainfluenza Virus, and Canine Parvovirus. Of these, distemper, adenovirus, and parvovirus are considered core vaccinations.
The AAHA Guidelines recommends that puppies receive 3 vaccinations 3-4 weeks apart starting at 6-8 weeks of age. The dog should receive a booster 1 year after the final puppy vaccination, then should be revaccinated every 3 years.
i. Canine Distemper Virus
Distemper is a virus that spreads very easily from infected animals such as dogs, ferrets, racoons, and skunks. Dogs that become sick with distemper can show a variety of clinical signs including: vomiting, diarrhea, coughing, sneezing, nasal and ocular discharge, and neurological signs such as twitching and/or seizures. Distemper infections are frequently fatal, and even if a dog recovers from the initial illness, there are often long term complications in which death result.
ii. Canine Adenovirus
There are 2 strains of Adenovirus. Type 1 causes infectious hepatitis (liver disease) and Type 2 causes respiratory infections and can play a role in canine kennel cough infections. Adenovirus is spread from infected animals and can live in the environment for long periods of time. Your dog does not need direct contact with an infected animal to catch the disease. Many animals can carry the disease including racoons, skunks, foxes, wolves and coyotes. Adenovirus infections can lead to serious complications including liver disease, eye damage, pneumonia, encephalitis and death.
iii. Canine Parvovirus
Parvovirus is a virus that causes severe vomiting, diarrhoea, anorexia, and lethargy in dogs. Parvovirus is severe and can cause death. Dogs catch the disease by ingesting virus shed from infected dogs. The virus can live in the environment for a very long time, so it is not necessary for your dog to have contact with another dog to catch this disease. Dogs can catch the disease if they are not fully vaccinated and are exposed to the virus. This is why it is recommended to keep your puppy away from unvaccinated dogs and areas frequented by unvaccinated dogs until 2 weeks after the last puppy vaccination is given.
iv. Canine Parainfluenza
Parainfluenza is a common viral infection in dogs. It causes coughing and sneezing. Parainfluenza is frequently spread from dog to dog and can play a role in canine kennel cough infections. Parainfluenza infections can lead to more serious complications such as pneumonia. Parainfluenza is not a core vaccination but is included in the DA2PPv vaccination combination.
B. Non Core Vaccinations
Non core vaccinations are recommended for dogs at risk for infection but are not necessarily recommended for all dogs. Factors such as your dog’s lifestyle, health, medical history, and age can affect their level of risk. Your veterinarian can help you assess your dog’s need for non core vaccinations.
I. Bordetella bronchiseptica
Bordetella is a bacteria which is part of canine kennel cough. Bordetella is a highly infectious disease so this vaccine is recommended for all dogs who socialize with other dogs. Social situations include boarding, doggie daycare, puppy classes, dogs shows, or trips to the dog park. Bordetella vaccination will not stop your dog from getting kennel cough but it should make the disease milder should they catch kennel cough.
The bordetella vaccination is a bacterin vaccine (not a viral vaccine) so the duration of immunity (DOI) of the bordetella vaccination is short. Dogs at risk should be vaccinated every 6-12 months.
II. Leptospirosis
Leptospirosis is a disease which is spread through contaminated water from infected animals including cows and wildlife to dogs and people. The disease is caused by an infection of the Leptospira interrogans bacteria. Leptospirosis can cause symptoms ranging from fever to liver and kidney failure. It is possible to catch this disease from your dog. Leptospirosis can be fatal and can have serious long-term consequences. Leptospirosis vaccination is recommended for all dogs who drink from bodies of standing water, such as puddles or ponds.
Like bordetella, leptospirosis vaccination is a bacterin vaccine, and has a short DOI. Annual vaccination of dogs at risk is recommended.
III. Lyme Disease (Borrelia burgdorferi)
Lyme disease is caused by an infection of the Borrelia burgdorferi bacteria, which is transmitted by the bite of the blacklegged tick (also called the deer tick). Symptoms of Lyme disease include bull’s eye shaped rashes, fever, chills, fatigue, joint and muscle pain, and nervous system disorders.
Lyme disease is recommended only for dogs with a known risk of exposure who are living in or visit areas where the risk of infected ticks are considered to be high, or where the disease is known to be endemic (regularly found). For most dogs (and humans), prevention of the disease, by reducing the chance of tick bite, is considered more effective.
Lyme vaccine is a bacterin vaccination and has a short DOI. Revaccination every 12 months or less is recommended for at-risk dogs.
Please see our page on titre testing if you are interested in customizing your dog’s vaccination schedule.
