We recently wrote to our dog owners regarding the spread of canine influenza within Lower Manhattan. We wanted to follow up by speaking more about respiratory infections in dogs. Dr. Kristin Lester of our Seaport Animal Hospital expands upon this:
There you are, lying in bed, dreaming of taking little Fifi to the dog park the next day when through the darkness you hear the first muffled sounds of your beloved one starting to cough… Is this merely a nightmare? Or could it be… the dreaded Kennel Cough?!? You’ve heard about this disease, but wonder what it is, how it is transmitted, and what to do about it. The good news is that we are here to help arm you with information and take care of Fifi, so you both can rest peacefully.
Infectious tracheobronchitis, also known as Canine Contagious Cough Complex or “kennel cough,” is caused by a collection of highly contagious respiratory pathogens, not just Bordetella. In fact, multiple infectious organisms may be involved in a single case, including Bordetella bronchiseptica, parainfluenza virus, adenovirus type 2, distemper virus, influenza virus, herpesvirus, mycoplasma canis, respiratory coronavirus, pneumovirus, and canine reovirus. Bordetella bronchiseptica can also infect cats, rabbits and pigs. Rarely, kennel cough can be spread to humans; however there have only been a handful of cases and it is typically only a risk with severely immunocompromised people. Canine influenza, an uncommon contributor to kennel cough syndrome, typically causes much more severe disease with fever and pneumonia, but can start with the classic signs of coughing.
Kennel cough can occur year-round and the incubation period, time it takes from exposure to onset of symptoms, is 2 to 14 days. Dogs typically only show clinical signs for 1-2 weeks, but infected animals can continue to shed the organism via respiratory secretions for up to 3 months. Young, stressed, crowded or debilitated animals are more susceptible than adults. Furthermore, compromised respiratory health secondary to heavy dust, cigarette smoke, cold temperature and/or poor ventilation can also make animals more prone to infection. Infection is spread via animal-to-animal contact, aerosolized respiratory secretions or inanimate objects that get “blessed” by an infected animal. A single sneeze from Fifi can cover up to 20 feet from her cute pink nose!
Clinical signs in dogs typically include an acute-onset, non-productive, dry, hacking cough, with coughing fits occasionally ending in a terminal retch (that white foamy material that is brought up at the end of a hack). In addition to a cough, cats can develop sneezing and discharge from the nose and eyes. While typically limited to the upper respiratory tract, kennel cough can occasionally spread to the lower airways resulting in pneumonia. Uncomplicated upper respiratory cases typically do not entail a fever, poor appetite or significant lethargy, so these are important signs for which to watch when monitoring for progression to pneumonia.
If your dog or cat is coughing, it is important to bring them in to be evaluated by your veterinarian. Often times, the diagnosis of kennel cough can be made based on history and physical exam. Depending on exam findings, severity of signs or chronicity, your veterinarian may recommend chest x-rays to screen for complicating pneumonia and/or obtaining respiratory samples for infectious disease confirmatory tests to identify the exact combination of involved infectious agents to help guide therapy and gauge prognosis. The treatment for kennel cough often involves a course of antibiotics +/- other supportive care as needed based on severity and symptoms. Antibiotics will not help if the infectious agents are purely viral, but they will help prevent or treat secondary infection. As stated, it’s often times a combination of multiple infectious agents in a single case of kennel cough!
Vaccination is available for a number of the kennel cough organisms (Bordetella bronchiseptica, canine adenovirus type 2, canine parainfluenza virus, canine distemper, and canine influenza), but not all can be prevented. The canine influenza vaccination is especially recommended for dogs that travel to dog shows, race tracks or other high density areas, or if there is a documented case in the area. It is important to note that vaccination is NOT useful in a dog already incubating kennel cough. If you plan on boarding your dog and more than 6 months have passed since the last Bordetella vaccination, ideally booster that vaccine at least 5 days prior to boarding. As for canine influenza, if your dog has never had that vaccine, the initial vaccine MUST be followed by a booster in 3-4 weeks to provide any protection, and even so, protective immunity does not develop until at least 7-10 days after the SECOND vaccination. Furthermore, it may not fully prevent infection, but often times it can lessen the clinical signs and duration associated with disease. Recovering dogs that contracted kennel cough are typically immune to reinfection for 6-12 months afterward (assuming the same pathogens are involved with the repeat exposure).
If there is an outbreak in your area, but your dog is not yet showing symptoms, there are a couple things that may help keep Fifi healthy. First, ensure that the Bordetella vaccination is up to date (every 6 months), but remember that the vaccination will not help if your dog is already incubating the disease. Avoid contact as much as possible with potential sources of infection and ensure that your dog is otherwise as healthy as possible (not stressed or sick from something else) and ready to fight off the invading pathogen if exposed. If you notice anything out of the ordinary, including but not limited to coughing, lethargy, decreased appetite, fever, etc, please bring Fifi in to be examined sooner rather than later to minimize the risk of serious disease developing.
My sincere wishes for the health and happiness of all your furry family members. Until next we meet, keep well and enjoy the rest of your summer.