Canine Influenza Vaccine: Does Your Dog Need the Dog Flu Shot?

Canine influenza — commonly called dog flu — is a highly contagious respiratory illness that affects a large proportion of exposed dogs. Unlike human flu, it doesn’t have a seasonal peak and can spread year-round wherever dogs congregate. The American Veterinary Medical Association¹ notes that approximately 80% of dogs exposed to canine influenza show clinical signs. The vaccine is noncore, meaning it’s recommended based on lifestyle rather than for every dog — but for dogs that board, attend daycare, or frequent dog parks, it’s an important conversation to have with your veterinarian. Here’s what pet parents need to know.

What Is Canine Influenza?

Canine influenza is a respiratory infection caused by type A influenza viruses adapted to spread in dogs. Dogs typically develop a persistent cough lasting 10–21 days, along with fever (up to 104–105°F), nasal discharge, lethargy, and reduced appetite, according to the AVMA¹. Eye discharge is also common.

The virus spreads through respiratory droplets and direct contact — coughing, sneezing, shared water bowls, and contaminated surfaces. Infected dogs can begin spreading the virus before they show symptoms, making early containment difficult. The AVMA¹ notes that dogs can remain contagious for up to four weeks after exposure.

One important reassurance: canine influenza does not spread to people. There is no evidence that either strain of dog flu is contagious to humans.

What Strains Does the Canine Influenza Vaccine Cover?

Two strains of canine influenza currently circulate in the United States:

A bivalent vaccine that protects against both H3N8 and H3N2 is available and is generally preferred over single-strain vaccines, as it provides broader coverage. Monovalent vaccines targeting one strain individually are also available if clinically appropriate.

Does Your Dog Need the Canine Influenza Vaccine?

The canine influenza vaccine is classified as noncore by AAHA, meaning veterinarians recommend it based on individual risk factors rather than for all dogs. Whether your dog should be vaccinated depends primarily on their social life and geographic location.

Good candidates include dogs that: - Stay at boarding kennels or attend doggy daycare - Attend training classes, dog shows, or competitions - Visit dog parks or grooming facilities frequently - Travel to areas with documented active outbreaks (recent documented states include California, Illinois, Georgia, Virginia, and New York)

Dogs with limited contact with other dogs may not need the vaccine, but it’s worth asking your veterinarian about current activity in your area. Outbreaks can occur with limited warning, and dogs with no prior immunity are highly susceptible.

Talk to your vet before any planned boarding stay — and read more about why vaccination timing matters for dogs and cats.

What Is the Canine Influenza Vaccine Schedule?

Dogs should be at least 6 weeks old before receiving their first dose, according to PetMD². The initial series requires two doses given 2–4 weeks apart. Annual boosters are recommended for dogs that remain in high-exposure situations.

Planning ahead matters for this vaccine. Full immunity doesn’t develop until approximately two weeks after the second dose. For a dog preparing for a boarding stay, the recommended timeline is:

If your dog is overdue on a booster, your veterinarian will advise whether a single catch-up dose or a new two-dose series is appropriate based on the time elapsed. Learn more about what a routine vet checkup typically involves when scheduling vaccinations.

What Are the Side Effects of the Canine Influenza Vaccine?

The canine influenza vaccine is generally well-tolerated. Most dogs experience only mild, temporary reactions similar to those with other vaccines.

Common reactions include:

Rare but more serious reactions — such as hives, facial swelling, vomiting, difficulty breathing, or collapse — require immediate veterinary attention. These are uncommon with the canine influenza vaccine but can occur with any injection.

Contact your veterinarian promptly if you notice any concerning symptoms after vaccination.

How Much Does the Canine Influenza Vaccine Cost?

According to PetMD², the canine influenza vaccine typically costs $30–$75² per dose. For the initial two-dose series, pet parents should budget for two separate veterinary visits within 2–4 weeks of each other. Annual booster costs fall in the same $30–$75² per dose range.

Pricing varies by location, veterinary practice, and whether the vaccine is bundled into a wellness package. Bivalent vaccines may cost slightly more than single-strain versions, but they’re generally preferred for broader protection.

Can Pet Insurance Help With Canine Influenza Vaccine Costs?

Routine vaccines aren’t covered by standard accident and illness pet insurance plans. However, optional preventive care add-ons can help offset the cost of annual vaccinations and wellness visits, including the canine influenza vaccine for dogs with high-exposure lifestyles. Learn more about how preventive care add-ons work.

If a dog contracts canine influenza — which can happen even in vaccinated dogs, since the vaccine reduces severity and duration rather than guaranteeing complete prevention — an accident and illness plan may help cover the cost of treatment for a covered condition.

Frequently Asked Questions

Is canine influenza the same as the common cold or kennel cough?

No. Canine influenza is a distinct influenza virus, separate from kennel cough (which is primarily caused by Bordetella bronchiseptica and canine parainfluenza virus) and from the human cold or flu. Some symptoms overlap — coughing, nasal discharge, lethargy — but the causative agents are different. A dog can have both kennel cough and canine influenza at the same time.

Can my dog get the flu from me, or give it to me?

Neither. Canine influenza viruses (H3N8 and H3N2) do not infect people. The AVMA¹ states there is no evidence that dog flu is contagious to humans. Similarly, human influenza viruses do not infect dogs under normal circumstances.

How long does the canine influenza vaccine last?

Annual boosters are the standard recommendation for dogs that remain at risk. The vaccine does not provide multi-year immunity like some other core vaccines. For dogs with ongoing boarding or daycare exposure, staying current on the annual schedule is important.

My dog’s boarding facility requires the canine flu vaccine — how far in advance do I need to start?

Start the two-dose series at least four weeks before the boarding date. The first dose goes on day one, the second dose follows 2–4 weeks later, and it takes about two more weeks for full immunity to develop. If you wait until a week before, your dog won’t have adequate protection by the time they check in.

Does the canine influenza vaccine prevent infection completely?

No. Like influenza vaccines in people, the canine influenza vaccine is designed to reduce the severity and duration of illness, not to guarantee that a dog will never become infected. Vaccinated dogs who are exposed to the virus typically experience milder symptoms and recover faster than unvaccinated dogs, and they shed the virus for a shorter period.

Choosing pet insurance is about more than preparing for emergencies — it’s also about finding coverage that fits your pet’s needs and your budget. The right plan can help support both everyday peace of mind and long-term financial flexibility.

With Spot Pet Insurance, pet parents can customize their coverage with reimbursement options from 70% to 90%, annual limits up to unlimited, and deductible choices that work for their lifestyle. Spot also offers optional preventive care add-ons that can help with the eligible costs of routine services like annual exams, dental cleanings, and certain vaccines. Learn more about what pet insurance covers.