Title: Kennel cough

{{short description|Upper respiratory infection affecting dogs}}
[[File:Bordetella bronchiseptica.jpg|thumb|A scanning electron micrograph (SEM) depicting a number of Gram-negative ''[[Bordetella bronchiseptica]]'' bacteria.]]
[[File:Parainfluenza virus TEM PHIL 271 lores.jpg|thumb|Transmission electron micrograph of parainfluenza virus. Two intact particles and free filamentous nucleocapsid.]]

'''Kennel cough''' (also &quot;canine infectious respiratory disease&quot; (CIRD), &quot;canine infectious respiratory disease complex&quot; (CIRDC) or &quot;canine infectious [[tracheobronchitis]]&quot; (CIT)) is an [[upper respiratory infection]] affecting [[dog]]s.&lt;ref&gt;{{cite web |last=Crawford |first=Cynda |title=Media Briefing on Canine Influenza |url=https://www.cdc.gov/media/transcripts/t050926.htm |publisher=Media Relations, [[Centers for Disease Control and Prevention]] |date=September 26, 2005 |access-date=2012-01-24 |archive-url=https://web.archive.org/web/20111015221601/http://www.cdc.gov/media/transcripts/t050926.htm |archive-date=October 15, 2011 |url-status=live }}&lt;/ref&gt; There are multiple causative agents, the most common being the bacterium ''[[Bordetella bronchiseptica]]'' (found in 78.7% of cases in Southern Germany), followed by [[canine parainfluenza virus]] (CPIV; 37.7% of cases), and to a lesser extent [[canine coronavirus]] (9.8% of cases).&lt;ref name=Schulz_2014/&gt; It is highly contagious;&lt;ref name=Ettinger_1995&gt;{{cite book |author1=Ettinger, Stephen J. |author2=Feldman, Edward C. |title=Textbook of Veterinary Internal Medicine |edition=4th |publisher=W.B. Saunders Company |year=1995 |isbn=0-7216-6795-3}}&lt;/ref&gt; however, adult dogs may display immunity to reinfection even under constant exposure.&lt;ref name=Bemis_1977&gt;{{cite journal |last1=Bemis |first1=DA |last2=Carmichael |first2=LE |last3=Appel |first3=MJ |title=Naturally occurring respiratory disease in a kennel caused by ''Bordetella bronchiseptica'' |journal=The Cornell Veterinarian |date=April 1977 |volume=67 |issue=2 |pages=282–293 |pmid=870289}}&lt;/ref&gt; Kennel cough is so named because the infection can spread quickly among dogs in the close quarters of a [[kennel]] or [[animal shelter]].

Viral and bacterial causes of canine cough are [[droplet-borne infection|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,&lt;ref name=Ettinger_1995/&gt; 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]].&lt;ref name=&quot;Sherding G. 2006&quot; /&gt;

==Symptoms==
The [[incubation period]] is 5–7 days (with a range of 3–10).&lt;ref name=&quot;Sherding G. 2006&quot;&gt;{{cite book|last1=Sherding G.|first1=Robert|title=Saunders Manual of Small Animal Practice|year=2006|publisher=W.B. Saunders|location=Saint Louis|isbn=9780721604220|pages=151–153|edition=Third|doi=10.1016/B0-72-160422-6/50014-0}}&lt;/ref&gt; Symptoms can include a harsh, dry cough, retching, sneezing, snorting, gagging or vomiting in response to light pressing of the [[Vertebrate trachea|trachea]] or after excitement or exercise. The presence of a [[fever]] varies from case to case.{{citation needed|date=September 2020}}

===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]] virus (CDV) or [[canine mastadenovirus A]] (formerly canine adenovirus-1). 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]], [[conjunctivitis]], and fever, in addition to a hacking cough.&lt;ref name= Thrusfield_1991&gt;{{cite journal|last1=Thrusfield|first1= M|last2=Aitken|first2=C|last3=Muirhead|first3=R|title= A Field Investigation of Kennel Cough: Incubation Period and Clinical Signs|journal= Journal of Small Animal Practice|date= 1991|doi=10.1111/j.1748-5827.1991.tb00550.x|volume=32|issue= 5|pages=215–220}}&lt;/ref&gt;

==Transmission==
Viral infections such as canine [[parainfluenza]] or [[Canine coronavirus#Canine respiratory coronavirus|Canine respiratory coronavirus]] are only spread for roughly one week following recovery;&lt;ref name=&quot;Sherding G. 2006&quot; /&gt; however, respiratory infections involving ''B. bronchiseptica'' can be transmissible for several weeks longer.&lt;ref name=Bemis_1977/&gt; While there was early evidence to suggest that ''B. bronchiseptica'' could be shed for many months post-infection,&lt;ref name=Bemis_1977/&gt; a more recent report places detectable nasal and [[Pharynx|pharyngeal]] levels of ''B. bronchiseptica'' in 45.6% of all clinically healthy dogs.&lt;ref name=Schulz_2014/&gt; 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.&lt;ref name=Iemura_2009&gt;{{cite journal|last1=Iemura|first1=R|last2=Tsukatani|first2=R|last3=Micallef|first3=MJ|last4=Taneno|first4=A|title=Simultaneous analysis of the nasal shedding kinetics of field and vaccine strains of Bordetella bronchiseptica|journal=The Veterinary Record|date=26 December 2009|volume=165|issue=25|pages=747–751|pmid=20023279}}&lt;/ref&gt;  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.&lt;ref name=Iemura_2009/&gt;

==Treatment and prevention==
{{See also|DA2PPC Vaccine}}
[[Antibiotic]]s are given to treat any [[bacteria]]l infection present. [[Cough medicine|Cough suppressants]] are used if the cough is not productive. [[NSAID]]s are often given to reduce fever and upper respiratory inflammation. Prevention is by [[vaccination|vaccinating]] for canine [[Adenoviridae#Animals|adenovirus]], [[Canine distemper|distemper]], parainfluenza, and ''[[Bordetella]]''.  In kennels, the best prevention is to keep all the cages disinfected. In some cases, such as &quot;doggie daycares&quot; 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]], even after receiving the vaccination, a dog can still contract mutated strains or less severe cases.{{citation needed|date=September 2020}}

In 2024, reports of a “mysterious” canine respiratory disease was reported on the east coast of the United States that could not be identified as one of the dozen known respiratory diseases. This new organism has caused thousands of dogs to become ill and has been fatal to some. Symptoms include runny eyes, sneezing and coughing but should not be confused with kennel cough. &lt;ref&gt;{{Cite web |date=2025-10-29 |title=Revival Animal Health |url=https://www.revivalanimal.com/learning-center/kennel-cough-or-something-new-understanding-the-emerging-dog-respiratory-virus |access-date=2025-12-24 |website=Revival Animal Health |language=en}}&lt;/ref&gt;

==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.&lt;ref name=edinboro_2004&gt;{{cite journal|last1=Edinboro|first1=C|last2=Ward|first2=M|last3=Glickman|first3=L|title=A Placebo-controlled Trial of Two Intranasal Vaccines to Prevent Tracheobronchitis (kennel Cough) in Dogs Entering a Humane Shelter|journal= Preventive Veterinary Medicine|date=February 2004|volume=62|issue=2|pages=89–99|doi=10.1016/j.prevetmed.2003.10.001|pmid=15156996|pmc=7126306}}&lt;/ref&gt; 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]] and [[nasal vaccine|intranasal]].&lt;ref name=thrusfield_1989&gt;{{cite journal|last1=Thrusfield|first1=M|last2=Aitken|first2=C|last3=Muirhead|first3=R|title= A Field Investigation of Kennel Cough: Efficacy of Vaccination|journal= Journal of Small Animal Practice|year= 1989|doi=10.1111/j.1748-5827.1989.tb01471.x|volume=30|issue=10|pages=550–560}}&lt;/ref&gt; 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 [[adenovirus]] 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.&lt;ref name=edinboro_2004/&gt; 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.&lt;ref name=Schulz_2014&gt;{{cite journal|last1=Schulz|first1=B|last2=Kurz|first2=S|last3=Balzer|first3=H|last4=Hartmann|first4=K|title= Detection of Respiratory Viruses and Bordetella Bronchiseptica in Dogs with Acute Respiratory Tract Infections|journal= The Veterinary Journal|date= September 2014|doi=10.1016/j.tvjl.2014.04.019|volume=201|issue=3|pages=365–369|pmid=24980809|pmc=7110455}}&lt;/ref&gt;

==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.&lt;ref name= Schulz_2014/&gt; Several opportunistic invaders have been recovered from the respiratory tracts of dogs with kennel cough, including ''[[Streptococcus]]'', ''[[Pasteurella]]'', ''[[Pseudomonas]]'', and various [[coliform]] bacteria. These bacteria have the potential to cause [[pneumonia]] or [[sepsis]], which drastically increase the severity of the disease. These complications are evident in [[thoracic]] [[radiographic]] examinations. Findings will be mild in animals affected only by kennel cough, while those with complications may have evidence of segmental [[atelectasis]] (collapsed lung) and other severe side effects.&lt;ref name=Greene_2006&gt;{{cite book|last1=Greene|first1=Craig E|title=Infectious Diseases in Dogs and Cats|year=2006|location=St Louis|chapter= 6|edition= third}}&lt;/ref&gt;

==See also==
{{Portal|Dogs}}
* [[Atypical Canine Infectious Respiratory Disease Complex]]
* [[Bronchitis]]
* [[Canine influenza]]
* [[Rhinotracheitis]]

==References==
{{reflist|30em}}

==External links==
* [https://online.zoetis.com/gb/en/conditions/pages/kennelcough.aspx Zoetis (formerly Pfizer Animal Health) Entry on Canine Infectious Tracheobronchitis - Kennel Cough] {{Webarchive|url=https://web.archive.org/web/20130922012430/https://online.zoetis.com/GB/EN/Conditions/Pages/KennelCough.aspx |date=2013-09-22 }}
* [http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/121619.htm Merck Veterinary Manual Entry on Canine Cough] {{Webarchive|url=https://web.archive.org/web/20090302000120/http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/121619.htm |date=2009-03-02 }}

[[Category:Dog diseases]]
[[Category:Infectious diseases]]
[[Category:Respiratory diseases]]