Canine Influenza, Reprise

Several years ago, I wrote an article about Canine Influenza. Back in 2004, canine flu was emerging here in the United States and appeared in pockets around our country. It created big headlines in the greyhound racing circuit in Florida. Today, canine influenza has been reported in over 40 states and thousands of dogs have been infected.

So what’s changed? Just as with humans, newer strains of influenza have become widespread. Formerly, our concern with canine flu was the H3N8 strain. Recently, the H3N2 variant has spread among dogs. Of even more concern, this strain has the ability to jump across species and can affect cats as well. A nationally reported episode occurred in an Indiana shelter in 2016 where infected dogs spread respiratory disease to cats within the shelter.

The signs of canine flu can be mild or severe. The predominant sign is coughing. There can be sneezing and a nasal discharge. If there’s a fever, then appetite may be decreased and a dog may be lethargic. With severe disease, the fever climbs and breathing can be labored. Secondary infection with opportunistic bacteria may worsen pneumonia. Fortunately, fatality with flu is less than 10% of affected dogs. Most dogs do recover in 2-3 weeks. Sometimes the mild form of flu can resemble kennel cough, which is a disease of the upper airways in a dog’s chest. A raspy cough is the hallmark of that problem.

Virtually all dogs are susceptible to canine flu, but certainly those that congregate with other dogs are more so. Dogs who compete in shows or sporting events, go to grooming parlors, are boarded or who play at parks are at greater risk. Naturally, veterinarians, shelter staff and kennel operators are vigilant about detecting and preventing cases of flu.

Canine flu vaccines which protect against single strains of the virus have been available for years. Vaccine manufacturers have hastened production of products which now offer protection against both strains of canine flu. Individual owners should contact their veterinarians to decide if a pets’ lifestyle warrants the need for vaccination.