The dog flu is an infectious respiratory disease caused by a canine influenza virus (CIV). It can be passed from dog to dog, but no transmission from dogs to humans has been reported. Most cases are mild, but the infection can sometimes be severe.

Knowing the signs and symptoms of dog flu can help you know when it's time to visit the vet.

What Causes Dog Flu?

There are two canine influenza virus (CIV) strains that cause dog flu: H3N8 and H3N2 (1).

H3N8 Originates from Horses

In 2004, some cases of respiratory infections in dogs were reported in Florida (2). It soon started to spread among dogs. Scientists believe that the virus acquired a modification that enabled it to jump species from horses to dogs. Since then, the H3N8 strain is considered a dog-specific influenza virus.

H3N2 originates from Birds

Similarly to H3N8, the H3N2 strain was transmitted to dogs from a different species; in this case, it came from birds. This strain of the virus first appeared in 2007 in South Korea, and soon after, in China, Thailand, and Canada. In April 2015, the H3N8 was first reported in Chicago and has now spread to most parts of the United States (3).

The Influenza Virus Is Easily Transmitted

Both strains are very contagious, and when a dog is exposed to the virus, the risk of infection is very high. Most dogs have no immunity against these viruses because the first transmission was only reported a few years ago, and dogs don’t have a long history with influenza viruses.

The virus is airborne and is transmitted through respiratory secretions when the dog sneezes, barks, or coughs. It can also spread through contact with contaminated surfaces, as well as water and food bowls. The virus spreads easily when many dogs come together, which is the case in dog parks, shelters, and kennels.

The incubation period for the canine influenza virus is two to four days. This is the time between infection and the appearance of symptoms. During this time, the dog is already contagious and continues to spread the virus for another seven to ten days.

Around 20% of infected dogs show no signs of the disease but can still transmit it to other dogs (4). These dogs are asymptomatic carriers.

Dog Flu Symptoms

Dog flu symptoms vary from very mild to severe. Some infected dogs don’t show any signs, and most dogs recover within two to three weeks. In severe cases, the dog flu can lead to pneumonia. Around five to eight percent of infected dogs die (5). In contrast to the human influenza virus, the canine influenza virus is less seasonal and can occur throughout the year.

Typical symptoms include:

• Coughing
• Sneezing and running nose
• Eye discharge
• Fever
• Breathing difficulties
• Lethargy
• Loss of appetite

Dog flu cannot be diagnosed by symptoms alone because other respiratory conditions may cause similar symptoms. A blood test detecting influenza antibodies is necessary to confirm that the influenza virus causes the symptoms.

Treatment of the Dog Flu Is Mainly Supportive

Similar to the human influenza virus, no medication kills the virus. Instead, the treatment of the dog flu is supportive. The dog needs to rest and may need to receive fluids as supportive care.

Non-steroidal anti-inflammatory drugs (NSAIDs) can help relieve influenza-related pains, reduce fevers, and improve wellbeing.

Because viral infections make the dog susceptible to secondary bacterial infections, antibiotics may be necessary to treat those infections.

Also, CBD oil can relieve dog flu-associated symptoms. This natural compound from the cannabis plant aids fighting off pain, inflammation, stress, and anxiety. Since the flu is associated with all these symptoms, CBD oil can make the flu more bearable for your dog.

CBD oil works by supporting the endogenous endocannabinoid system. Like humans, dogs also produce endocannabinoids that act on specific receptors and regulate physiological processes, such as inflammation and pain perception (5).

PetFX® CBD products are 100% THC-free and won’t get your dog high. This is crucial because dogs are especially susceptible to THC’s action.

CannaLove™ CBD K-9 Soft Chews are the perfect treat to cheer your dog up while suffering from the symptoms of the flu.

CannaLove™ K-9 Pain Relief Hemp Oil can also be added to your dog’s favorite food as an easy way to administer CBD.

Prevention 

When flu cases occur in your area, keep your dog away from public places, such as dog parks or kennels. If you touch other dogs, wash your hands and arms, and change your clothing before touching your dog.

Keeping your pet’s areas clean, as well as making sure any veterinary or boarding facilities are clean, is helpful. SteriCide™ by PetFX® is effective against canine influenza as well as a host of other diseases.

Another way to protect your dog from the flu is through vaccinations. Vaccinations are especially important when your dog is old or has other health conditions that make your dog more susceptible to severe infections. There are vaccines against both the H3N8 and H3N2 strains of the flu. Only one of those two strains is likely in your area, so your dog may not need both vaccines.

The Bottom Line

The dog flu and its associated symptoms are mostly harmless but should not be taken lightly. Although dog flu symptoms are not a dangerous threat for most dogs, the dog flu can cause severe symptoms and lead to other complications in some dogs. In any case, the flu is unpleasant and affects wellbeing, similarly to the flu in humans.

Preventive measures make it less likely for your dog to catch the flu. If your dog happens to get the flu, you cannot do much besides treating the related symptoms. The most important care is to support his well being and to reduce anxiety and stress.