My first experience with kennel cough was working in boarding kennels quite a few years ago in NZ. Vaccines were available but it was not required to vaccinate to board dogs at that time. We had a dog that had recently been in quarantine from overseas, she developed a cough, then dogs in nieghbouring pens developed a cough, it soon went through the entire kennels, effecting the dogs to differing degrees. Some just coughed when excited or exersing, others got a bit snotty and coughed up flem, while others had no problems. I likened it to the common cold in humans. We had three week old German Shepherd puppies at the house that contracted KC which was scary, also old dogs seemed to get knocked around by it, however everyone got over it. It was a big learning curve for me. Vaccines do not work against all strains and if a new strain arrives outbreaks will occur, I believe. Bit like swine flu.