What You Need to Know About Dog Flu — Prevention and Treatment

A sick dog with an ice pack on this head and a thermometer in his mouth.
A sick dog with an ice pack on this head and a thermometer in his mouth.

As a veterinarian with the American Animal Hospital Association (AAHA) and the mother of two young children, I’m busy 24-7. To keep the family machine running smoothly, I record everyone’s daily activities in my iPhone and hope for no slip ups; missing a karate class can be catastrophic to a 5- and 7-year-old. However, when it comes to health, I’m hypervigilant; sickness can derail a smooth-running train. That’s why I’m first in line every fall for a flu shot. And so are my dogs. The canine influenza vaccine (or simply called dog flu) is important if your dog comes in contact with other dogs. The virus is spread when respiratory secretions are exchanged among dogs who are barking, sneezing, or coughing. Outbreaks occur year-round but tend to spike during months when families travel with their pets and board them.

The two strains of dog flu

There are two strains of dog flu in this country. H3N8 reared its head in 2004 on Greyhound racetracks in Florida. It spread like wildfire until a vaccine was developed.

More recently, in spring 2015, the Asian-born H3N2 clobbered Chicago. Unfortunately, there was no vaccine to protect against the strain.

When the outbreak hit, veterinary hospitals were packed to capacity with sick dogs. Some came in coughing, others had labored breathing. Dogs were tired and had mucus dripping from their eyes and nose. The sickest dogs experienced all these signs. Veterinarians faced the challenge of treating the sick dogs while not infecting the healthy ones.

In the epicenter of the outbreak, Dr. Jerry Klein, Chief Veterinary Officer of the American Kennel Club and seasoned emergency clinician in Chicago, also emphasized that the outbreak “encouraged cooperation among area hospitals as we tried to share data, follow best practices, secure space for dogs that needed hospitalization and educate pet owners about what was happening.”

Another noted Chicago veterinarian, Dr. Natalie Marks, co-owner of AAHA-accredited Blum Animal Hospital, recalled the outbreak of dog flu:

“It was controlled chaos in our hospital. We evaluated all patients in exam rooms instead of in the treatment area where we keep our equipment in an effort to avoid contaminating dogs who were visiting for regular checkups. If patients had a normal appetite, body temperature, oxygen level and energy level, we managed them as outpatients. However, if they had a fever, were vomiting, not eating, or were incredibly lethargic, we began in-hospital therapy until their stability level met our criteria for outpatient care.” The critically ill received oxygen therapy, IV fluids, and antibiotics to protect against bacterial invaders taking advantage of weakened lungs.

A dog receiving oxygen therapy.
A dog receiving oxygen therapy. Photography courtesy AAHA/Robin Baker.

So many questions about the dog flu

Chicago pet owners whose dogs received the flu diagnosis were exploding with questions. My childhood friend, Kathleen, was one of them. (When you’re a vet, friends will seek your advice during a crisis!) She texted me about her Labrador mix, Winnie, who was being treated as an outpatient. Here were her concerns and my text responses, plus updates of what we know now:

Can I catch H3N2 from Winnie?
As far as we know, H3N2 does not infect people.

Can Winnie infect my cat?
Probably not, but we’re not sure yet. (Update: Reports now indicate that cats can be infected with H3N2; several in Midwest shelters have contracted it.)

She’s keeping us up all night with her coughing. How can I make it stop?
There’s no easy solution to quell the coughing, but ask your vet about cough suppressants. Bringing up mucous and phlegm is actually a GOOD thing. You can encourage this by using a humidifier to moisten her airways. My personal favorite? Keep her in the bathroom with the door closed while you shower. The warm, wet air will help her to cough up the mucous.

She’s supposed to go back to doggie daycare next week. Is that OK?
Actually, no. You should wait until her cough has disappeared completely. (Update: Because so little was known about H3N2, veterinarians made educated guesses. Now we know that coughing dogs can spread the disease for roughly three weeks and should be isolated from other dogs for that length of time.) In Chicago, Dr. Marks reminded the pet parents of her recovering patients to stay clear of communal areas, including “dog parks, elevators in high-rises, friends’ homes and places of work.”

Where will dog flu hit next?

Though we haven’t had any reported cases of H3N2 at the hospital where I practice in New Jersey, my pet parents continue to ask questions: “Will it hit our area?” “Can a dog die from it?” Reports show that 80 percent of dogs exposed to H3N2 get sick from it. The remaining 20 percent don’t get sick but harbor the virus and can spread it. The percentage of dogs who die from the disease is less than 10 percent.

In November 2015, the H3N2 vaccine was developed, and the virus has traveled to more than 30 states. It could continue to spread if pet owners don’t vaccinate their dogs.

So, what’s a pet parent to do about the dog flu?

If your dog exhibits signs of dog flu, visit your veterinary practice immediately. If the vet suspects H3N2, he may swab your dog’s nasal passage or extract a vial of blood for diagnosis. Many signs associated with dog flu, like coughing, lethargy and eye and nose discharge, are also indicators of other illnesses. Coughing is almost always serious; your dog could be suffering from a number of diseases including heart failure, heartworms and “kennel” cough.

Do you know the dog flu symptoms?

Thousands of dogs have contracted H3N2. Could yours be next? If your dog is lethargic, coughing, sneezing, or has a runny nose and eyes, he could have dog flu. The best way to help prevent dog flu is to vaccinate against it. Less than 10 percent of dogs suffering from H3N2 will die.

Read more about dog health care on Dogster.com:

Editor’s note: This article appeared in our magazine. Have you seen the new Dogster print magazine in stores? Or in the waiting room of your vet’s office? Subscribe to Dogster and get the bimonthly magazine delivered to your home.

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