New concerns respiratory dog illness could spread as families travel with pets for holiday

There are new concerns that a mystery dog illness could spread as many families travel with their pets for the holiday.

The respiratory illness is affecting dogs in several states nationwide and leaving owners, like Lauren Celaya, worried about their four-legged family members.

"Over the course of about two days, she continued to have that like dry hacking cough. And it just kind of progressed from there," said Celaya, who is from North Carolina.

Six weeks ago, Celaya noticed her German Shepherd Maddy showing signs of what she and her vet initially believed was typical kennel cough -- until it didn't go away.

"Unfortunately, it is extremely contagious. And our French Bulldog got it as well," Celaya said.

Similar cases are now popping up around the country. Kaleigh Gordon and Ryan Wilson, from New Hampshire, are also dealing with the mystery contagious respiratory disease with their 1-year-old Australian Shepherd Tobi.

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"You're like, you know, do we bring him to the emergency vet," Wilson asked.

"When he was coughing, it was he was like gagging because he was coughing up like phlegm," Gordon added.

Veterinarian Dr. Lindsey Ganzer, who has already treated 35 dogs with the mystery disease, said the first symptom of coughing can last for weeks.

"Starting with a cough [and] nasal discharge progressing to more of a wet cough, lethargy, fever, not wanting to eat," Dr. Ganzer described. "So you'll notice that their respiratory rate and effort are increased. Their gums might turn blue or purple."

Now, as 50 million Americans hit the road for the holidays, concerns about their own furry friends brought sharply into focus

One person even posted on Facebook wondering if boarding her pet is okay.

"Most important thing is to avoid any areas where there are a lot of dogs in that space. So avoid boarding them. Avoid doggie daycares, going to the groomer, going to dog parks," Dr. Ganzer suggested.

Another person questioned if cats are affected, too.

"Right now, we're only seeing it in dogs. Typically, bacteria and viruses don't necessarily spread from species to species," Dr. Ganzer said.

Perhaps the number one question so many want to be answered is how can they keep their fur babies safe.

"Definitely get seen by a veterinarian sooner rather than later. The earlier that treatment starts, the better chance they have of not progressing and developing into a pneumonia," Dr. Ganzer said.