Kennel cough, also known as canine infectious respiratory disease, formally canine infectious

tracheobronchitis Tracheobronchitis is inflammation of the trachea and bronchi. It is characterised by a cough, fever, and purulent (containing pus) sputum and is therefore suggestive of pneumonia. It is classified as a respiratory tract infection. Tracheobronchitis ...

, is an

upper respiratory infection An upper respiratory tract infection (URTI) is an illness caused by an acute infection, which involves the upper respiratory tract, including the human nose, nose, Paranasal sinus, sinuses, pharynx, larynx or trachea. This commonly includes nasal ...

affecting

dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...

s. There are multiple causative agents, the most common being the bacterium ''

Bordetella bronchiseptica ''Bordetella bronchiseptica'' is a small, gram-negative, rod-shaped bacterium of the genus ''Bordetella''. It can cause infectious bronchitis in dogs and other animals, but rarely infects humans. Closely related to '' B. pertussis''—the obl ...

'' (found in 78.7% of cases in Southern Germany), followed by canine

parainfluenza virus Human parainfluenza viruses (HPIVs) are the viruses that cause human parainfluenza. HPIVs are a paraphyletic group of four distinct single-stranded RNA viruses belonging to the ''Paramyxoviridae'' family. These viruses are closely associated wit ...

(37.7% of cases), and to a lesser extent

canine coronavirus Canine coronavirus (CCoV) is an enveloped, positive-sense, single-stranded RNA virus which is a member of the species ''Alphacoronavirus 1.'' It causes a highly contagious intestinal disease worldwide in dogs. The infecting virus enters its hos ...

(9.8% of cases). It is highly contagious; however, adult dogs may display immunity to reinfection even under constant exposure. Kennel cough is so named because the infection can spread quickly among dogs in the close quarters of a

kennel A kennel is a structure or shelter for dogs. Used in the plural, ''the kennels'', the term means any building, collection of buildings or a property in which dogs are housed, maintained, and (though not in all cases) bred. A kennel can be made o ...

animal shelter An animal shelter or pound is a place where stray, lost, abandoned or surrendered animals – mostly dogs and cats – are housed. The word "pound" has its origins in the animal pounds of agricultural communities, where stray livestock would ...

. Viral and bacterial causes of canine cough are spread through airborne droplets produced by sneezing and coughing. These agents also spread through contact with contaminated surfaces. Symptoms begin after a several day incubation period post-exposure, and in most cases will clear up on their own. However, in young puppies or immunocompromised animals, mixed or secondary infections can progress to lower respiratory infections such as

pneumonia Pneumonia is an inflammatory condition of the lung primarily affecting the small air sacs known as alveoli. Symptoms typically include some combination of productive or dry cough, chest pain, fever, and difficulty breathing. The severity ...

Symptoms

The

incubation period Incubation period (also known as the latent period or latency period) is the time elapsed between exposure to a pathogenic organism, a chemical, or radiation, and when symptoms and signs are first apparent. In a typical infectious disease, the i ...

is 5–7 days (with a range of 3–10). Symptoms can include a harsh, dry cough, retching, sneezing, snorting, gagging or vomiting in response to light pressing of the

trachea The trachea, also known as the windpipe, is a Cartilage, cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all air-breathing animals with lungs. The trachea extends ...

or after excitement or exercise. The presence of a

fever Fever, also referred to as pyrexia, is defined as having a body temperature, temperature above the human body temperature, normal range due to an increase in the body's temperature Human body temperature#Fever, set point. There is not a single ...

varies from case to case.

Types

Although kennel cough is considered to be a multifactorial infection, there are two main forms. The first is more mild and is caused by ''B. bronchiseptica'' and canine parainfluenza infections, without complications from

canine distemper Canine distemper virus (CDV) (sometimes termed footpad disease) is a viral disease that affects a wide variety of mammal families, including domestic and wild species of dogs, coyotes, foxes, pandas, wolves, ferrets, skunks, raccoons, and felin ...

virus (CDV) or canine

adenovirus Adenoviruses (members of the family ''Adenoviridae'') are medium-sized (90–100 nm), nonenveloped (without an outer lipid bilayer) viruses with an icosahedral nucleocapsid containing a double-stranded DNA genome. Their name derives from the ...

(CAV). This form occurs most regularly in autumn, and can be distinguished by symptoms such as a retching cough and vomiting. The second form has a more complex combination of causative organisms, including CDV and CAV. It typically occurs in dogs that have not been vaccinated and it is not seasonal. Symptoms are more severe than the first form, and may include

rhinitis Rhinitis, also known as coryza, is irritation and inflammation of the mucous membrane inside the nose. Common symptoms are a stuffy nose, runny nose, sneezing, and post-nasal drip. The inflammation is caused by viruses, bacteria, irritants o ...

conjunctivitis Conjunctivitis, also known as pink eye, is inflammation of the conjunctiva, outermost layer of the white part of the eye and the inner surface of the eyelid. It makes the eye appear pink or reddish. Pain, burning, scratchiness, or itchiness may ...

, and fever, in addition to a hacking cough.

Transmission

Viral infections such as canine

parainfluenza Human parainfluenza viruses (HPIVs) are the viruses that cause human parainfluenza. HPIVs are a paraphyletic group of four distinct single-stranded RNA viruses belonging to the '' Paramyxoviridae'' family. These viruses are closely associated wit ...

are only spread for roughly one week following recovery; however, respiratory infections involving ''B. bronchiseptica'' can be transmissible for several weeks longer. While there was early evidence to suggest that ''B. bronchiseptica'' could be shed for many months post-infection, a more recent report places detectable nasal and pharyngeal levels of ''B. bronchiseptica'' in 45.6% of all clinically healthy dogs. This has potentially expanded the vector from currently or recently infected dogs to half the dog population as carriers. To put the relative levels of shedding bacteria into perspective, a study analyzing the shedding kinetics of ''B. bronchiseptica'' presents the highest levels of bacterial shedding one week post-exposure, with an order of magnitude decrease in shedding observed every week. This projection places negligible levels of shedding to be expected six weeks post-exposure (or approximately five weeks post-onset of symptoms). Dogs which had been administered intranasal vaccine four weeks prior to virulent ''B. bronchiseptica'' challenge displayed little to no bacterial shedding within three weeks of exposure to the virulent strain.

Treatment and prevention

Antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of ...

s are given to treat any

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...

l infection present. Cough suppressants are used if the cough is not productive.

NSAID Non-steroidal anti-inflammatory drugs (NSAID) are members of a therapeutic drug class which reduces pain, decreases inflammation, decreases fever, and prevents blood clots. Side effects depend on the specific drug, its dose and duration of ...

s are often given to reduce fever and upper respiratory inflammation. Prevention is by

vaccinating Vaccination is the administration of a vaccine to help the immune system develop immunity from a disease. Vaccines contain a microorganism or virus in a weakened, live or killed state, or proteins or toxins from the organism. In stimulating ...

for canine

, distemper, parainfluenza, and ''

Bordetella ''Bordetella'' () is a genus of small (0.2 – 0.7 µm), gram-negative coccobacilli of the phylum Pseudomonadota. ''Bordetella'' species, with the exception of '' B. petrii'', are obligate aerobes, as well as highly fastidious, or difficult ...

''. In kennels, the best prevention is to keep all the cages disinfected. In some cases, such as "doggie daycares" or nontraditional playcare-type boarding environments, it is usually not a cleaning or disinfecting issue, but rather an airborne issue, as the dogs are in contact with each other's saliva and breath. Although most kennels require proof of vaccination, the vaccination is not a fail-safe preventative. Just like human

influenza Influenza, commonly known as "the flu", is an infectious disease caused by influenza viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These symptoms ...

, even after receiving the vaccination, a dog can still contract mutated strains or less severe cases.

Vaccines

To increase their effectiveness, vaccines should be administered as soon as possible after a dog enters a high-risk area, such as a shelter. 10 to 14 days are required for partial immunity to develop. Administration of ''B. bronchiseptica'' and canine parainfluenza vaccines may then be continued routinely, especially during outbreaks of kennel cough. There are several methods of administration, including

parenteral A route of administration in pharmacology and toxicology is the way by which a drug, fluid, poison, or other substance is taken into the body. Routes of administration are generally classified by the location at which the substance is applied. ...

and

intranasal Nasal administration, popularly known as snorting, is a route of administration in which drugs are insufflated through the nose. It can be a form of either topical administration or systemic administration, as the drugs thus locally delivere ...

. However, the intranasal method has been recommended when exposure is imminent, due to a more rapid and localized protection. Several intranasal vaccines have been developed that contain canine

in addition to ''B. bronchiseptica'' and canine parainfluenza virus antigens. Studies have thus far not been able to determine which formula of vaccination is the most efficient. Adverse effects of vaccinations are mild, but the most common effect observed up to 30 days after administration is nasal discharge. Vaccinations are not always effective. In one study it was found that 43.3% of all dogs in the study population with respiratory disease had in fact been vaccinated.

Complications

Dogs will typically recover from kennel cough within a few weeks. However, secondary infections could lead to complications that could do more harm than the disease itself. Several opportunistic invaders have been recovered from the respiratory tracts of dogs with kennel cough, including ''

Streptococcus ''Streptococcus'' is a genus of gram-positive ' (plural ) or spherical bacteria that belongs to the family Streptococcaceae, within the order Lactobacillales (lactic acid bacteria), in the phylum Bacillota. Cell division in streptococci occurs ...

'', ''

Pasteurella __NOTOC__ ''Pasteurella'' is a genus of Gram-negative, facultatively anaerobic bacteria. ''Pasteurella'' species are nonmotile and pleomorphic, and often exhibit bipolar staining ("safety pin" appearance). Most species are catalase- and oxidase-p ...

'', ''

Pseudomonas ''Pseudomonas'' is a genus of Gram-negative, Gammaproteobacteria, belonging to the family Pseudomonadaceae and containing 191 described species. The members of the genus demonstrate a great deal of metabolic diversity and consequently are able ...

'', and various

coliform Coliform bacteria are defined as either motile or non-motile Gram-negative non- spore forming Bacilli that possess β-galactosidase to produce acids and gases under their optimal growth temperature of 35-37°C. They can be aerobes or facultativ ...

bacteria. These bacteria have the potential to cause

sepsis Sepsis, formerly known as septicemia (septicaemia in British English) or blood poisoning, is a life-threatening condition that arises when the body's response to infection causes injury to its own tissues and organs. This initial stage is follo ...

, which drastically increase the severity of the disease. These complications are evident in

thoracic The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the crea ...

radiographic Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view the internal form of an object. Applications of radiography include medical radiography ("diagnostic" and "therapeut ...

examinations. Findings will be mild in animals affected only by kennel cough, while those with complications may have evidence of segmental

atelectasis Atelectasis is the collapse or closure of a lung resulting in reduced or absent gas exchange. It is usually unilateral, affecting part or all of one lung. It is a condition where the alveoli are deflated down to little or no volume, as distinct ...

and other severe side effects.

References

{{reflist, 30em

External links

Zoetis (formerly Pfizer Animal Health) Entry on Canine Infectious Tracheobronchitis - Kennel Cough

Dog diseases Infectious diseases Respiratory diseases