As we continue down the road of re-emerging dog diseases, our next stop is with the bacteria most-commonly associated with kennel cough: Bordetella bronchiseptica. This bacteria was seen regularly before vaccines were developed but decreased during the 90’s and early 2000’s. It had also been somewhat overshadowed by other respiratory pathogens, especially the various flu various that have mutated to infect dogs. While theories for its return have been linked to both anti-vaccination support and increases in coyotes & foxes in the wild, all we know is that it is definitely making a comeback.
Bordetella is a bacteria that is spread through aerosolized respiratory secretions much like COVID. So, the smaller the space, the greater the chance of transmission. Kennels were the most common places for infection and the reason for Bordetella being called the kennel-cough bacteria. However, as more people are grooming their dogs, we have seen much higher rates of infection from these smaller facilities with a lot more air blowing around. In the normal dog airways, the surfaces are covered with microscopic fingers called cilia. These are constantly pushing material attached to the surfaces up & out of the respiratory tract. The nastiest aspect of Bordetella is that it has evolved to attach to this cilia and render it useless. So, not only are the bacteria plugging up the respiratory tract, but it’s preventing the tract from removing other pathogens and general schmutz as well. So, there are often other things causing concurrent problems. This is what we no longer call Bordetella the “kennel cough” pathogen; it usually has friends along with it.
Dogs will usually start coughing within a matter of days, but it can take up to 2 weeks to start seeing signs. This is why kennels and groomers have such issues preventing this. The cough is typically worse right when dogs wake up and when they get excited or active. Most of these infections will resolve on their own without needing treatment beyond cough suppressants at bedtime. However, young and/or unvaccinated dogs can cough for almost 2 months with the potential to development into a full-blown pneumonia. Antibiotics will be necessary in these patients.
Vaccines have been available and proven safe for decades. The older forms were squirted into the nose to create what’s called local immunity. This is very effective and decreases chances for vaccine reactions. That said, dogs hate having things shoved up their noses. Injectable vaccines are more recently available, but we tend to reserve these for aggressive patients as prevention of the disease is not as high as with the nasal form. The newest and most commonly used vaccine is an oral form. It seems to provide the same level of prevention as the nasal form without the sneezing and general discomfort. Even if your dog doesn’t board or go to the groomer, the prevalence of Bordetella is high enough that this low-risk vaccine should be part of every dog’s vaccine program.