Canine Influenza – Symptoms, Diagnosis & Treatments of Dog Flu

Canine Influenza – Symptoms, Diagnosis & Treatments of Dog Flu

You may notice some social media feeds warning the pet owners about a highly contagious Canine Influenza, aka dog flu, that is raging all over the USA. Even some newspapers like Fox news and Newsweek also publishing their reports about the flu.

The truth is, yes, some dogs are catching flu in different US states. To be honest, there is also several shocking news about local outbreaks of the flu. For example, a flu outbreak affected more than 1,000 dogs in Chicago in 2015.

But no, there is nothing to panic. In this article, we will cover everything you may need about the canine influenza virus and dog flu.

What is the Canine Influenza Virus?

The canine influenza virus is a member of the type A Influenza virus genus in the family Orthomyxoviridae. It is a virus responsible for the so-called dog flu.

The Canine Influenza virus is mostly adapted to dogs. This virus strains are named after two surface antigens. They are the neuraminidase (N) and hemagglutinin (H) proteins. There are and 9 neuraminidase antigens (N1 to N9) and 16 hemagglutinin antigens (H1 to H16).

There are two different kinds of Canine Influenza virus in North America: H3N8 CIV and H3N2 CIV.


Around the year 2000, the A/H3N8-type of canine influenza virus (CIV) was born out the A/H3N8-type of equine influenza virus (EIV). This virus basically infected horses but it spreads from horses to ducks and dogs.

The H3N8 virus can be defined by their genetic variation, the growth rate on different biological cells, infection methods, hemagglutinin (H) cleavage, receptor specificity, and growth in dog and horse tracheal explants cultures.

This virus shows the same growth level on different hosts, especially on the MDCK cells. But different hosts have different levels of sensitivity of infection. This virus preferred α2-3- over α2-6-linked sialic acids to infect the hosts.

The H3N8 is first reported in racing greyhounds in the US in 2004. There was an outbreak of H3N8 between 2004 and 2005. Almost 20,000 dogs were affected from 13 different states.


The Canine influenza H3N2 has been a recently encountered strain in the US. Researchers believed that this virus originates in Asia. This virus was first reported in South Korea.

H3N2 was first introduced to the US (in Orange County) in 2015. The affected dog was imported from South Korea. After the first breakout, it spreads widely and causes a severe outbreak in many regions.

How Does the Dog Flu Virus Spread?

This virus spreads primarily through the large-particle respiratory droplet transmission. The spreading process may occur in two approaches: direct contact and indirect contact.

The direct contact includes muzzle to muzzle, nose to nose, friendly licks (dog kisses), or through the air. When an infected dog barks, sneezes, or coughs in the open air, it makes the air affected. Whenever a healthy dog sneezes on that air, it becomes infected too. An infected dog sends aerosolized particles almost 20 feet through the air!

The indirect contact may happen through physical commodities such as water bowls, feeding bowls, toys etc. This Influenza virus can live on those up to 48 hours!

Is Canine Influenza Contagious?

Canine Influenza virus is a highly contagious virus. In recent years, this dog flu becomes a live horror show for the pet owners.

The Centers for Disease Control and Prevention (CDC) reports that 2017/2018 is a horrific year for this flu. In the first week in January, 22.7 out of 100,000 hospitalizations in the US were for the flu. This number was doubled from the previous week.

Watch this quick video from National Geographic to get a quick recap on what the Canine Flu is all about.

Prevention of Canine Influenza Virus

Good hygiene prevents most of the viruses. Always maintain a healthier procedure while handling your own or any unknown pet. Most importantly, the pet owners should take total responsibility for their pets as well as use their common sense to keep their dogs safe from dog flu.

To help the dog owners, we have listed a few veterinarians suggested tips to prevent this fatal virus.

➢ If a dog suffers from an active respiratory illness or if he recently recovered from any kind of respiratory illness, keep it strictly at home. A couple of weeks will be a good choice. But try to make it to 4 weeks: it’s the safest choice. The affected dog can fully recover from the illness during this time. It also prevents the affected dog from spreading potential infection transmission to other dogs.

➢ Inform your veterinarian if your puppy stayed at boarding kennel recently.

➢ If you have to send your puppy in a boarding kennel in the near future, research about that first. Make sure the kennel is safe from viruses and other infectious diseases. You know, there is nothing more important than safety.

➢ Do not allow your doggy to share dishes or toys with an unknown dog.

➢ Ensure a balanced diet for your dog. You should also feed health supplements if your veterinarian suggests doing so.

➢ Thoroughly disinfect any equipment, clothing, or surfaces that might be infected with respiratory secretions. A commercial disinfectant or 10% bleach is an ideal choice for this.

➢ Thoroughly wash your hands before AND after you are having contact with another infected dog.

➢ If your dog has been lost for a day or even for a few hours, contact a reputed dog rescue organization first and visit the veterinarian as soon as you rescue your dog and the state hospitals for an experienced veterinarian.

➢ Be aware that your pet is updated with all canine influenza vaccines.

➢ Mostly, remain alert about canine influenza outbreak in your area.

Vaccines of Dog Flu

The Animal and Plant Health Inspection Service (APHIS) of the United States Department of Agriculture (USDA) approved the first canine influenza vaccine in June 2009.

Currently, the most commonly used vaccine is Bivalent Vaccine. It is used to heal both H3N2 and H3N8 CIV. The Vanguard antigen is recommended for using the in healthy dogs ≥ 8 weeks of age. You should inject 2 doses 3 weeks apart.

But you cannot vaccinate the pregnant dogs. Aside from the pregnant dogs, you may also notice some side effects because of the dog flu vaccine. Most common effects are anaphylaxis and/or other similar hypersensitivity reactions.

Symptoms of Canine Influenza Virus

Almost 80% of infected dogs show dog flu symptoms. We’ve compiled a list of symptoms to identify whether your pet is sick or not?

Persistent cough

Does your dog cough persistently after staying at a kennel? Oops! It’s perfect morbidity of having canine influenza. This soft or wet cough may last 3 to 4 weeks.

Additionally, they will sneeze continuously. The inflammation of nasal lining causes this. Do not confuse dog flu with kennel cough.

Loss of appetite

Your dog won’t express any interest in food. Even when he feels hungry, you cannot feed him. The loss of appetite is quite natural for one or two days. But if it continues, you must be worried.


Few dogs are sleepy by nature. That’s why the pet owner didn’t notice the sleep cycle of their pets. But sleepiness doesn’t mean they sleep all the time.

However, the affected dog will feel sleepy all the time. He will lose interest in playing with you like before. Rather than that he will like to doze on his tent or kennel.


Actually, fever isn’t a disease at all. It is a symptom of diseases. Like most other diseases, canine influenza infection also causes the fever to your pet.

The normal temperature of a healthy dog lies between 99.5F and 102.5F degrees. So, you should read the accurate body temperature using a thermometer. You may also feel their paws and ears manually. You will feel hot if your dog has a fever.

Nasal discharge

Along with cough and fever, liquid nasal discharge also a common sign of flu infection. The nasal discharge directly connected with the respiratory issue. As the worst case scenario, you may notice colorful discharge mostly greenish. Trust me, it’s really a bad sign.

Breathing difficulties

An increased respiratory rate and breathing difficulties cause several diseases like canine influenza H3N2 infection, pneumonia etc. If you do not take quick action, it may affect the lungs too.

There are several signs of canine influenza virus. If your dog shows any of these signs, contact your veterinarian right now.

dog flu guide
Guide to dog flu and the canine influenza viruses (H3N2).

Dog Flu Treatment

As the old saying goes, “An ounce of prevention is worth a pound of cure!” So, you should try to prevent this flu of dog rather than providing treatment.

Actually, there isn’t much residential treatment exists for this flu. All that you can is being supportive and keeping your dog comfortable. Few dogs may need extra support. Make sure you are providing everything for your dog just like your vet suggests.

If it seems like your dog cannot recover from this illness, you should consult with the vet again. He may provide some additional nutritional plan or may prescribe antibiotics too.

Additional tips: If your dog is highly infected, the treatment may cost you a few bucks. To keep you calm about financial issues during this time, it is wiser having pet insurance.

Any dog may be affected by canine influenza. But it’s not the end of the earth. Just sit back and relax. Proper support from you will help the pet to recover from illness.

If you have any queries about canine influenza virus, shoot it via the comment box below. Our expert team will answer your queries as soon as possible.

Stay happy with your dog!