Medically reviewed by Dr. Dean Severidt, Director of Medical Excellence, October 9, 2026.
When cold and flu season rolls in, most of us worry about ourselves and our families getting sick. Here’s something that surprises a lot of pet parents: dogs can catch the flu too. It isn’t the same virus that sends you to bed. Dogs have their own version, called canine influenza, and it spreads easily anywhere dogs spend time together.
Most cases are mild, and knowing the basics makes it much easier to keep yours healthy. At Huebner Oaks Veterinary in San Antonio, TX, we want you to know what to watch for, when to call us, and how to time the vaccine so your dog is ready for the holiday season ahead.
Dog Flu at a Glance
What it is: a contagious respiratory illness that spreads easily wherever dogs spend time together
What to watch for: a lingering cough, sneezing, nasal discharge, fever, low energy, and less interest in food
When to call us: as soon as you notice a cough or any of these symptoms
When to vaccinate: about six weeks before boarding, daycare, or travel, since the two-dose series takes three to six weeks to work
What Is Canine Influenza?
Canine influenza, often called dog flu, is a highly contagious respiratory disease caused by two flu viruses that are specific to dogs.
Most dogs have never been exposed to either virus, so they have no built-in immunity. Nearly every dog who’s exposed becomes infected, whatever their breed, age, or overall health. According to the American Veterinary Medical Association (AVMA), about 80% develop symptoms. The other 20% look perfectly healthy but can still pass the virus along.
There’s no evidence that people can catch canine influenza. Cats occasionally can, though it’s uncommon and seen mostly in shelters.
Is There a Dog Flu Season?
Not really. Human flu peaks in fall and winter, but canine influenza can show up at any time of year. It tends to appear in local outbreaks that flare up and then fade.
So why talk about it now? The holidays are when dogs mix the most. Boarding, daycare, grooming appointments, and travel all pick up around San Antonio and Shavano Park this time of year. More dogs sharing space means more chances for a respiratory virus to move from one dog to the next.
Protecting Every Dog at Huebner Oaks Veterinary in San Antonio, TX
At Huebner Oaks Veterinary, our AAHA-accredited hospital is joined by dog and cat boarding, pet daycare, and grooming, so we know how busy things get when dogs share space during the holidays. Whether your dog is a daycare regular, has a boarding reservation, or is due for a wellness exam, our team can help you decide whether the canine influenza vaccine fits your dog’s lifestyle and schedule both doses before you travel. Visit us at 12058 Vance Jackson Rd, Suite 101, San Antonio, TX 78230, call us at (210) 796-9958, or email us at info@huebneroaksvet.com with questions or to schedule your dog’s visit.
How Does Dog Flu Spread?
Canine influenza travels in respiratory droplets. Your dog can pick it up through:
Nose-to-nose greetings, licking, and play
Coughing, sneezing, and barking from an infected dog nearby
Shared items such as water bowls, toys, leashes, and kennel surfaces
The hands and clothing of people who’ve handled an infected dog
The virus can survive for a day or two on surfaces, but common disinfectants kill it easily. Timing is the tricky part. Dogs are most contagious in the first few days after exposure, before they show any signs, and they can keep spreading the virus for up to four weeks after they were first exposed.
What Are the Symptoms of Dog Flu?
Signs can appear anywhere from one to eight days after exposure, depending on the strain. Watch for:
A cough that lingers, often for 10 to 21 days
Sneezing
Thick nasal discharge
Runny eyes
Fever, often 104 to 105 degrees Fahrenheit
Low energy
Less interest in food
Dog flu is one of several illnesses behind canine cough, often called kennel cough. They look alike, so only a lab test, usually a nose or throat swab, can tell which one your dog has.
Most dogs have a mild illness and recover fully within two to three weeks. There’s no medication that treats the virus itself, so care focuses on comfort: rest, plenty of fluids, and good nutrition while your dog’s body does the work. A smaller group, about 10% to 20%, according to the AVMA, develops complications such as bacterial pneumonia and needs more care. Puppies, senior dogs, and dogs with other health conditions are most at risk.
When should I call my veterinarian?
Call us at Huebner Oaks Veterinary as soon as you notice a cough or any of the signs above. If your dog is having trouble breathing, seems extremely tired, or stops eating, don’t wait. Please call before you bring your dog in so we can keep other patients from being exposed. In the meantime:
Keep your dog home and away from other dogs
Tell any daycare, boarding, grooming, or training facility your dog visited recently
Ask us when it’s safe for your dog to be around other dogs again. As a precaution, the AVMA recommends keeping them apart for four weeks from the day signs first appear
When Should I Vaccinate My Dog Against Canine Influenza?
Earlier than you’d think. The vaccine needs time to work, so the calendar matters as much as the shot.
How does the vaccine schedule work?
The canine influenza vaccine is given as two doses, two to four weeks apart. Protection builds one to two weeks after the second dose, and a single dose is unlikely to protect a dog in a group setting. Add it up and the full series takes three to six weeks to do its job.
If your dog will be boarding, going to daycare, or traveling, aim to start about six weeks ahead. If your dog’s stay is sooner than six weeks out, talk to us about timing now. After the first series, one booster a year keeps protection current.
One more thing worth knowing: the vaccine won’t always prevent infection. What it does is make illness milder and shorter, and it reduces how much virus a dog spreads to others.
Which dogs benefit most from the dog flu vaccine?
Canine influenza is a lifestyle vaccine, which means it isn’t one every dog needs. The American Animal Hospital Association (AAHA) recommends deciding based on each dog’s risk. Veterinarians often suggest it for dogs who regularly:
Stay at boarding facilities
Go to daycare or dog parks
Visit the groomer
Take part in dog shows or sporting events
Travel
AAHA also recommends the vaccine that covers both strains. If your dog fits any of those descriptions, our team at Huebner Oaks Veterinary is glad to talk through the canine influenza vaccine with you.
Everyday Ways to Lower Your Dog’s Risk
Vaccines are one layer of protection. Simple habits are another:
Keep a coughing or sneezing dog home
Steer clear of dogs who are obviously sick
Wash your hands after petting other dogs
Skip shared water bowls and toys outside your home
Watch for canine influenza alerts around San Antonio, and avoid places where dogs gather until an outbreak passes
If your dog boards or goes to daycare, it’s fair to ask the facility how it handles infection control. The AVMA suggests asking about routine cleaning, whether respiratory illness has been a problem, how sick dogs are separated, and how pet parents are notified.
Want help deciding which precautions fit your dog? Bring your questions to your dog’s next wellness exam at Huebner Oaks Veterinary.
Frequently Asked Questions About Canine Influenza
Can I catch canine influenza from my dog?
No. Canine influenza isn’t known to spread from dogs to people. Cats can occasionally catch it, but that’s uncommon.
How long is a dog with canine influenza contagious?
Up to four weeks after they were first exposed. They’re most contagious early on, often before any symptoms show.
How is dog flu treated?
There’s no medicine that targets the virus itself, so treatment focuses on comfort: rest, fluids, and good nutrition. If complications like pneumonia develop, we’ll provide more care.
How long does the canine influenza vaccine take to work?
Plan on three to six weeks from the first dose. Your dog needs two doses spaced two to four weeks apart, then another week or two for protection to build. If your dog has boarding, daycare, or travel coming up, aim to start about six weeks ahead. If it’s sooner than that, talk to us now about timing.
Is dog flu the same as kennel cough?
Not exactly. Kennel cough is a catch-all name for contagious coughs in dogs, and canine influenza is one of the causes. A lab test is the only way to know which one your dog has. If your dog starts coughing, give us a call.
Get Your Dog’s Flu Vaccine in San Antonio, TX
Holiday plans come together fast. If your dog will be boarding, playing at daycare, or traveling in the next couple of months, talk with us about canine influenza now. If the stay is less than six weeks away, we can help you plan around the timing.
Not sure if the vaccine is right for your dog? Our veterinary team will look at your dog’s lifestyle and help you decide. Book a visit and we’ll map out the timing together.
Sources
American Veterinary Medical Association. (2026). “Canine influenza.” AVMA. https://www.avma.org/resources-tools/pet-owners/petcare/canine-influenza
American Veterinary Medical Association. (2026). “Canine influenza: Veterinary resources.” AVMA. https://www.avma.org/resources-tools/animal-health-and-welfare/animal-health/canine-influenza-veterinary-resources
American Animal Hospital Association. (2022). “Key Vaccination: Bordetella, Canine Parainfluenza, and Canine Influenza.” AAHA. https://www.aaha.org/resources/2022-aaha-canine-vaccination-guidelines/bordetella-canine-parainfluenza-and-canine-influenza/
University of Florida Shelter Medicine Program. (2017). “Canine influenza confirmed in 8 states; should shelters and rescue groups be vaccinating?” University of Florida College of Veterinary Medicine. https://sheltermedicine.vetmed.ufl.edu/2017/06/06/canine-influenza-confirmed-in-8-states-should-shelters-and-rescue-groups-be-vaccinating/
Centers for Disease Control and Prevention. (2024). “About Dog Flu.” CDC. https://www.cdc.gov/flu-in-animals/about/canine-flu.html