Updated - Oct 25th, 2023
Canine influenza, otherwise known as influenza A virus, dog flu, or CIV, is an infectious respiratory disease seen in dogs.
Dog flu has been reported in most states of the U.S., and is caused by one of two types of canine influenza virus, either H3N2 or H3N8. Canine influenza virus is not known to infect humans, but in dogs is known to cause flu-like clinical signs including coughing, fever, nasal discharge, sneezing, and malaise. Pneumonia due to secondary bacterial infections can develop in severe cases. Canine influenza virus can be confused with bordetella or kennel cough, however dogs with flu acting sicker than dogs with kennel cough. Canine influenza is rarely fatal, but is highly contagious and can spread like wildfire throughout dog populations.
Fortunately, a canine influenza vaccine has been developed to protect vulnerable dogs from dog flu. This article will give you information on what canine flu shots are available, how they work, and if the vaccine is a good idea for your dog. Pet owners will also learn how much a dog flu shot costs and any adverse effects associated with this vaccine.
What is the canine influenza vaccine, and how does it work?
The canine influenza vaccine is made up of both strains of canine influenza virus – H3N8 and H3N2 – which makes the vaccine ‘bivalent’. Canine influenza vaccines are killed vaccines, which means they contain inactivated (killed) canine influenza virus. The killed influenza viruses found in the vaccine stimulate a dog’s immune system to create antibodies against dog flu without causing disease.
Dogs that have been vaccinated against canine influenza may still show symptoms of dog flu if they are exposed to canine influenza virus, however, vaccinated dogs tend to have milder symptoms and shed less virus into the environment.
All canine influenza vaccines available in the U.S. are FDA approved, and are available at most veterinary clinics nationwide.
There are currently two bivalent canine influenza vaccines available and both are FDA-approved. There is also a monovalent canine influenza vaccine (only contains one strain of influenza) but in general that vaccine is only recommended in specific circumstances. In general, the bivalent vaccine is recommended instead of the monovalent. Canine influenza vaccines are available in veterinary practices nationwide, with no need to see a veterinary specialist to get the vaccine.
What is the vaccine schedule for the canine influenza vaccine?
According to the 2022 American Animal Hospital Association (AAHA) Vaccine Guidelines, the following is the recommended schedule for vaccinating dogs against dog flu:
- Puppies less than 16 weeks of age: two doses 2-4 weeks apart, followed by one dose one year after initial vaccine series
- Dogs older than 16 weeks of age with no influenza vaccine history: two doses 2-4 weeks apart, followed by one dose one year after initial vaccine series
- Dogs older than 16 weeks with established influenza vaccine history: 1 dose annually
Adult dogs that have not been vaccinated against canine influenza receive two doses because the first dose primes the immune system to create antibodies and the second dose boosts the levels of antibodies to a protective level.
Should I get my dog the canine influenza vaccine?
The canine influenza vaccine is considered a ‘non-core’ vaccine by veterinarians. This means that not every dog needs to be vaccinated against canine influenza. According to AAHA Guidelines, non-core vaccines are “recommended for some healthy dogs based on lifestyle, geographic location, and risk of exposure.” Your veterinarian may recommend your dog be vaccinated against influenza if they fit any of the following criteria:
- Your dog stays at daycare facilities (doggie day care) or is boarded
- Your dog attends group training classes
- Your dog visits dog parks frequently
- Your dog travels extensively
- Your dog participates in dog shows or agility events
- Your dog is older and has chronic respiratory illness or heart disease
- Your dog is brachycephalic (smush-face)
- You have dogs that are housed together in kennels, such as breeding or working dogs
If you board your dog, the facility may require you to vaccinate your dog against canine influenza before they will admit your dog. This is to prevent outbreaks in boarding facilities. To determine if the dog flu shot is right for your dog, talk to your veterinarian.
The canine influenza vaccine should not be administered to any dogs that are sick, have a fever, have auto-immune disorders, or are pregnant or nursing.
Are there any adverse reactions related to the canine influenza vaccine?
As with any vaccine, the canine influenza vaccine can induce adverse reactions in some healthy dogs. It is important for pet owners to realize that this vaccine is rigorously tested for purity and effectiveness and is administered annually to millions of dogs with no or minimal adverse effects. If a dog has a reaction to a vaccine that the problem isn’t with the vaccine, it is that the individual dog has a hypersensitive system (allergy).
The most common side effects associated with the canine influenza vaccine include:
- Pain and swelling at the injection site
- Low energy and appetite
- Mild vomiting (1-2x day of vaccination)
These short-term symptoms show that the vaccine is actually mounting an immune response and causing the immune system to make antibodies. If you notice that these side effects last longer than 48 hours, or if your dog is acting especially sore or limping, contact your veterinarian.
Rare but serious side effects of the canine influenza vaccine include:
- Persistent vomiting or diarrhea (longer than 1 day)
- Persistent swelling or pain at injection site, limping (longer than 48 hours)
- Swollen face
If your dog develops severe side effects after vaccination, seek immediate veterinary care.
How much does the canine influenza vaccine cost?
The cost of the canine flu vaccine varies based on the individual veterinary practice and geographic location. In general, the canine influenza vaccine costs approximately $20 to $55 per dose. This does not include the cost of the office visit if your veterinarian performs a physical examination before vaccinating your dog. Pet owners can save money on the canine influenza vaccine by:
- Enrolling in a preventative wellness plan that covers vaccines
- Utilize a low cost vaccine clinic
- Purchase a wellness plan from your veterinary clinic that includes all vaccines
- Ask for a technician only visit for vaccine boosters (as long as your dog is healthy and has a current physical examination on file)
When considering your dog’s health, remember that protecting them against viral infectious diseases to the best of your ability is as important to animal health as choosing the right food. While you can’t always prevent exposure to canine influenza virus, you can reduce the likelihood of your dog becoming sick or spreading the disease by following your reccommended puppy vaccine schedule.