Kennel Cough in Dogs: Signs, Care, and Prevention

Causes and how it spreads

Kennel cough is caused by a group of germs, and a dog is often infected with more than one at a time. The most common are the bacterium Bordetella bronchiseptica, canine parainfluenza virus, and canine adenovirus type 2. Canine influenza, canine herpesvirus, and mycoplasma can also play a part.

Viruses damage the lining of the airways, which makes it easier for bacteria to settle in. The inflammation can also reach the voice box, so some dogs sound hoarse or bark differently for a while. Stress, crowding, poor air flow, and irritants such as smoke, dust, or chemical fumes can make the illness worse.

The germs travel in droplets when a dog coughs or sneezes. They also pass through nose-to-nose contact and shared items such as water bowls, toys, and leashes. Hands and clothing can carry them from one dog to another. Bordetella can survive in the environment for at least 10 days.

Signs usually start 2 to 10 days after exposure, and dogs can pass the infection on before they start to cough. How long a dog stays contagious depends on the germ. Some dogs keep shedding germs for two weeks or more after they recover. A dog with Bordetella may stay contagious for up to eight weeks after the cough is gone, and sometimes longer.

The risk is highest where many dogs meet, including shelters, boarding kennels, daycare, grooming salons, dog parks, and vet waiting rooms.

Why newly adopted dogs often cough

Rescued dogs often spend time in shelters, foster homes, or transport alongside other dogs. Moving to a new home is stressful too, and stress can lower the body's defenses. Because signs take days to appear, a dog can pick up an infection before adoption and start coughing only after arriving home.

At Paw Squadron, every animal gets a checkup, treatment, vaccinations, and a microchip before adoption. Vaccines lower the risk and usually make the illness milder. No vaccine protects against every germ in this group, so a cough in the first days at home can still happen. If it does, call your vet and share the dog's vaccination record and recent history.

If you already have other dogs, many vets recommend keeping a newly adopted dog apart from them for about two weeks, even when the new dog seems healthy. This gives a hidden infection time to show before it can spread.

Signs to watch for

Many dogs with kennel cough stay bright and keep eating. Owners usually notice some of these signs.

• A harsh, dry cough that often sounds like a goose honk
• Gagging or retching after a coughing fit, which can look like vomiting or like something is stuck in the throat
• Coughing when the collar presses on the neck, or after excitement or exercise
• A hoarse or changed bark
• Sneezing, runny eyes, or a mild runny nose
• Mild tiredness or a smaller appetite

The cough is usually worst in the first few days and then slowly eases. Most dogs recover within one to two weeks, although a milder cough can linger for up to about three weeks.

When it is an emergency

Kennel cough can turn into pneumonia, and swelling in the throat can make breathing hard. Contact a vet right away if your dog breathes fast or with visible effort while resting, makes a loud or high-pitched noise when breathing in, or has bluish gums. A wet cough, fever, thick yellow or green discharge from the nose, refusing food, or unusual weakness can mean the infection has reached the lungs.

Some dogs need a vet check sooner. These include puppies, older dogs, dogs with heart or lung disease, and flat-faced breeds such as pugs and bulldogs, whose airways are already narrow. See your vet as well if the cough keeps your dog from resting or has not improved after about two weeks.

In a young or unvaccinated dog, a cough with fever and discharge from the eyes and nose can also be an early sign of distemper, a much more serious disease. Your vet can check for it.

How vets diagnose and treat it

Vets usually recognize kennel cough from the typical cough and a recent history of contact with other dogs. The exam includes listening to the chest and taking the dog's temperature. If pneumonia is possible, or if the cough does not fit the usual pattern, the vet may take chest X-rays. These also help rule out other causes of a honking cough, such as a collapsing windpipe, heart disease, or something stuck in the airway. Swab tests can identify the exact germs, which is useful in a severe case or a shelter outbreak.

Mild cases often need only rest and time while the body clears the infection. Antibiotics are not needed in every case, and vets usually keep them for dogs with signs of bacterial infection or pneumonia. If the cough is so strong that the dog cannot rest, the vet may prescribe a medicine to calm it, although these medicines are avoided when pneumonia is present. Dogs with pneumonia or breathing trouble may need hospital care with fluids and oxygen.

Human cough and cold medicines are best avoided unless your vet approves them. Some contain ingredients that are toxic to dogs, such as the sweetener xylitol.

Caring for a coughing dog at home

Home care is about comfort, rest, and keeping the infection from spreading. These steps are commonly recommended, and your vet can adjust them for your dog.

• Keep your dog away from other dogs, including parks, daycare, grooming, and busy walking routes. Ask your vet how long. Many recommend at least two weeks, and ideally until the cough is fully gone.
• Walk your dog on a harness instead of a collar so nothing presses on the windpipe.
• Keep walks short and calm, and avoid rough play and excitement that set off coughing fits.
• Keep the air clean. Do not smoke near your dog, and avoid dust, sprays, and strong fumes.
• Moist air can soothe the airway. Some vets suggest sitting with your dog in a steamy bathroom for a few minutes.
• Offer fresh water, and soft food if swallowing seems uncomfortable.
• Wash bowls, toys, and bedding, and wash your hands after handling the dog.

Call the clinic before your visit and say that your dog may have a contagious cough. The staff can then plan how to keep your dog away from other patients.

Other pets and people

Other dogs in the home are at the highest risk. Keep them apart from the coughing dog where you can, and ask your vet whether their vaccinations are up to date. Cats can also be infected with Bordetella, especially in crowded settings, so watch a household cat for sneezing or coughing.

The risk to healthy people is very low. Bordetella has occasionally caused illness in people, usually those with a weakened immune system. If someone in your home falls into that group, it is sensible to ask their doctor for advice and to be careful with hand washing.

How to prevent it

Vaccines are the main tool. The core vaccine recommended for all dogs covers canine adenovirus, and parainfluenza is often included in the same combination shot. The Bordetella vaccine, often called the kennel cough vaccine, comes as drops in the nose, a liquid given by mouth, or an injection. It is usually recommended for dogs that board, go to daycare or grooming, visit dog parks, or live with many other dogs. In some countries a canine influenza vaccine is also available.

These vaccines lower the chance of illness, make it milder, and reduce the risk of pneumonia. They do not fully prevent infection, so a vaccinated dog can still cough. Protection takes some time to build, so talk to your vet well before a kennel stay or a group class.

Everyday habits help too. Keep your dog away from dogs that are coughing, avoid shared water bowls in public places, and keep your home well aired and smoke free. A calm routine also lowers stress, which helps a newly adopted dog settle in and stay healthy.

If you are thinking about adopting, the Adoptions page shows the dogs looking for homes, and our FAQ answers common questions. For any cough in your own dog, your vet is the best person to ask.