US dogs suffer mystery respiratory illness: What we know so far

The mystery disease is causing dogs to experience symptoms that resemble other known respiratory illnesses, such as kennel cough and canine influenza.  (Image credit: Westend61 via Getty Images)

Dogs across the U.S. are getting sick with an unexplained respiratory illness. 

As of Monday (Nov. 27), at least 14 states, including Oregon, New Hampshire, Colorado and Massachusetts, have reported cases of pet dogs of different breeds developing symptoms including cough, runny nose, lethargy and a loss of appetite. In Oregon, for example, more than 200 cases have been reported since mid-August. However, the first cases of the outbreak are believed to have been reported in New Hampshire as early as last year, an expert told Live Science.