Dog Flu Never Left Chicago: Don't Panic


Facts about the dog flu are now, arguably, being exaggerated in the media…at least that seems to be the case. Headlines in Chicago area media on TV and in print, “The dog flu is back!”

Well, it’s likely the dog flu never really went anywhere.

First identified generically as a respiratory illness affecting dogs back in March, it was soon determined to be a dog flu. Scientists discovered the dog flu in Chicago is H2N2, a strain from Asia (not H3N8, the strain of canine influenza previously seen in the U.S.).  In early summer, at it’s height, some veterinary clinics saw 20 coughing dogs a day. Cook County administrator for the Department of Animal and Rabies Control Dr. Donna Alexander pronounced “an epidemic.”

I was among those leading the charge to keep dogs away from other dogs – even seemingly healthy dogs. That means avoiding other dogs on walks, and no dog training classes, no boarding, no socializing with dogs at pet stores, no doggy care, no visiting dog parks. The Chicago Park District warned dogs about going to Dog Friendly Areas (Chicago dog parks). Some dog businesses closed, at least for a time.

After likely thousands of dogs were sickened in the Chicago area, and eight died, the flu disappeared as fast as it came.

But did it really disappear? Around this time, some Chicago area shelters suffered with cases of the flu. And in the environment was it smoldering ready to kindled again? Very possible.

Ben Dalziel, who is in a group at Princeton that studies how infectious disease spread. The same group studied the dog flu strain H3N8, and is now looking at H3N2. The group also studies the spread of human illness.

The H3N2 virus has popped up again – some clinics that saw 20 cases of canine influenza daily are now seeing a a few coughing dog a week. It seems, most clinics aren’t seeing any.

Some veterinarians are again warning dog owners to keep their dogs away from other dogs. However, other veterinarians suggest that advice is not warranted, at least not at this juncture. Indeed the current dog flu reports do seem very limited to specific regions, and even associated with one PetSmart store in the South Loop.

It’s all about risk/benefit. The question today….Is the risk of getting the flu enough to warrant the repercussions of dogs limiting their social lives? It may sound cute, but seriously many dogs enjoy social activities, and so do their owners. And several dog owner now report seeing behavior problems in dogs that weren’t able to be appropriately socialized when the dog flu was spreading.

Dalziel says, in the larger population, realistically, most dogs aren’t exposed, most dogs that get the flu do recover. He’s says he unsure whether the mass of dog flu cases in Chicago at this moment should prompt such  precautions to cut off canine socialization.

“Having said that, so little is understood about H3N2, it makes prediction of how much the virus will reemerge in a community nearly impossible,” Dalziel adds.

The good news is that dogs previously sickened by H3N2 may have immunity, or some immunity. The problem is no one knows exactly. And while thousands of dogs wee sickened, and that is a big number, most dogs in the metro area were not. Are thousands that did become ill enough to protect the larger population (an affect called herd immunity)? Dalziel says he can’t say.

Is the H3N2 virus now endemic in Chicago – just here to stay at some level, until a vaccine specifically for this virus saves the day? Again, Dalziel says he can’t say. “It’s just too early to know that.” But he adds that is possible.

In attempting to better understand H3N2, Dalziel and others are comparing that virus to H3N8.

H3N8 seems to more quickly dead-end in a community (even before the H3N8 vaccine became available). Though in some places, H3N2 never becomes a community problem. For example, while H3N2 has been identified in New Jersey, New York and Los Angeles, so far, no major outbreaks in those places. While Chicago and Atlanta had epidemics. In Chicago, the virus spread throughout the region, hitting many suburbs. In Atlanta, that hasn’t occurred (at least not yet). Why? Dalziel laughs and says, “I wish we did know those answers, that’s what we’re studying.”

Here’s a Map of H3N2 dog flu cases

Also, one TV report stressed how cats a prone to the virus as well as dogs. Yes, cats can get this virus. It’s important to note, which the TV report did not, so far, only one cat in America has test positive for H3N2.

Dr. Melissa Bourgeois, a specialist in microbiology and Senior Specialist for Drug Safety at Merck Animal Health pints out the symptoms to watch for:

  •  Coughing
  • Discharge from the nose and/or eyes
  • Not wanting to exercise
  • Not wanting to eat
  • Hard for dog owners to tell, but a fever is another symptom. More profoundly affected dogs may have difficulty breathing and sometimes even develop pneumonia, and that’s when the canine influenza virus may potentially become life threatening.

Learn more about the Canine Influenza Virus HERE.