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Flashcards in Dog Respiratory tract infection Deck (27)
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NAme of respiratory tract infection in dogs

Infectious Tracheobronchitis
Kennel cough
CIRD -canine infectious respiratory disease


What causes Infectious Tracheobronchitis/ Kennel couch/ CIRD/ canine infectious respiratory disease

List of organisms that cause the above
 Bordetella bronchiseptica
 Canine parainfluenza virus
 Canine adenoviruses-1 and –2
 Canine herpesvirus
 Canine distemper virus
 More recently: canine respiratory coronavirus, equine influenza, strep.sp.


What is virus classification based on?

– The genome (RNA or DNA)
– Number and sense of RNA/DNA strands
– Morphology
– Genome sequence similarity
– Ecology


Canine parainfluenza virus

 Most common virus isolated from cases of kennel cough
 Paramyxovirus (same family as distemper)
 Virus excreted in oronasal secretions
 CPiV alone causes mild resp signs - cough and serous nasal discharge
 Virus multiplies in epithelial and lymphoid cells of respiratory tract
 Live attenuated vaccines available
 We don’t know too much about it


CAnine adenovirus 1 and 2

 CAV-1, systemic disease and can also cause Upper Resp TD, canine hepatitis (b;ue eye)
 CAV-2, respiratory disease
 Vaccines available – contain CAV-2 to vaccinate against both 1 and 2


CAnine herpes virus

 In puppies less than 2 wks of age virus generalises, fading puppy syndrome
 In older puppies and adults the virus is restricted to external mucous membranes – Upper Resp Tract and genital tract
 Clinical signs restricted to mild nasal serous discharge
 FPS  bigger deal, basically dying puppy
 There are vaccines you can give to botch to pass antibodies on and protect. But we don’t routinely vaccinate adult dogs against


Equine influenza virus

 Been in horses for 40 years
 H3 N8
 Causes typical flu
 Bit like people -vaccine, but virus evolves
 Cough 10-14 days
 Fever, nasal discharge
 Occasional death
 Antigenic shift
 Vaccine with periodic updates
 Competing horses have to be vaccinated


Resp disease in dogs equine influenza

 Upper respiratory tract disease
 10% inapparent infection
 80% mild “kennel cough”
 nasal discharge and cough (10-21 days )
 5-8% pneumonia and death
 high fever, dyspnoea, lung consolidation
 Incubation period 2-5 days
 Shedding period 7-10 days


Canine Influenza in the UK

 Outbreak of respiratory disease in foxhounds in Essex in September 2002
 Lung samples tested positive for H3N8
 Some dogs in the kennel are still antibody positive but low levels suggest virus is no longer present
 The AHT has done a serosurvey of 300 dog samples
 suggests the virus is not prevalent in the UK


Bordetella Bronchiseptica

Note, BB is probably the most typical organism to think of when thinking about kennel cough but kennel cough/ CIRD/ CRD are syndromes caused by MANY different organisms, not just BB!
 Gram negative small coccobacillus
 Same family as Bordetella pertussis
 Cause of respiratory disease in a wide range of host species


PAthogenesis Bordetella Bronchiseptica

Attaches to upper respiratory tract cilia
• Cause cilia stasis
 Stops mucociliary clearance
 Bacteria then colonise in the respiratory tract, causing disease

Incubation period – 6 days
 Attaches to ciliated epithelium
 Replicates and produces virulence factors
 Ciliostasis – releases toxins causing this


Clinical signs Bordetella Bronchiseptica

 Coughing (hacking)
 Nasal discharge
 Bronchopneumonia


Diagnosis Bordetella Bronchiseptica

 History and clinical signs
 Nasal/oropharyngeal swabs – v specific
 Transtracheal wash
 Bronchoalveolar lavage
 Charcoal Amies transport swabs – v specific
 Culture on selective agar – charcoal cephalexin


Treatment Bordetella Bronchiseptica

 Systemic antibacterials if clinically necessary
 BSAVA suggests that antibiotics are only indicated if clinical signs persist for greater than 10 days and/or the dog is systemically unwell
 Antitussives
 clearance of bacteria?
 Bronchodilators
 Expectorants


Antibacterial Sensitivities Bordetella Bronchiseptica

 Where necessary, Protect me guidelines suggest doxycycline or potentiated amoxycillin as the first choice antibiotics.
 Where cases fail to resolve, or if the lower respiratory tract is involved, culture and sensitivity and further investigations such as broncho-alveolar lavage may be indicated.


Carriers Bordetella Bronchiseptica

 Most animals actue infection, some bacteria shed for longer periods of time
 Prolonged shedding in clinically recovered animals (at least 3 months). Particularly important if multi dog household
 Epidemiological significance?
 Elimination following antibacterial therapy?


Interspecies Transmission: Bordetella Bronchiseptica

 Risk factors for Bb infection in cats – contact with dogs with respiratory disease
 Molecular typing – epidemiological links between isolates from dogs and cats


Vaccination Bordetella Bronchiseptica

 Avirulent live intranasal vaccine
 Efficacy – local and systemic protection
 Short duration of immunity
 Careful use where owner is immunocompromised


Zoonotic Risk of Bordetella Bronchiseptica

 Infection of a human from a rabbit previously reported
 Infection from dogs?
 Infection from vaccination (rare) – live vaccine so possible
 Also lot of vaccine is sneezes out
 Immunocompromised owners
– Some medics say all pets should be vaccinated to minimise human risk from field infection
– Some researchers say live vaccines should not be used.
– Where immunocompromised humans are in contact with dogs, the low but predictable risk of vaccination must be carefully weighed against the less predictable risk of clinical infection. Appropriate advice, including recommending at-risk owners contact their medical practitioner, should be offered.
– Humans have been known to end up with bronchiseptima due to BB assumed from pet


Control Bordetella Bronchiseptica in Boarding Kennels

 Vaccinated dogs
 Isolate affected dogs
 Adequate hygiene
 Prevent contact between animals
 Ventilation


Control Bordetella Bronchiseptica in Rescue kennels:

 Vaccination
 Isolate affected animals
 Batch incoming animals
 Adequate hygiene
 Ventilation

 Distemper and adenovirus are part of core vaccine every dog should get
 Parainfluenza is optional but often included in core vaccine
 Bb and herpes are additional you have to choose if going to get


PAthogenic fungi dogs

 Ringworm – most common
 Mycotic abortion
 Nasal aspergillosis dogs
 Nasal mycosis
 Cryptococcus in cats
 Malassezia in dogs


 Nasal aspergillosis dogs

 Chronic nasal discharge
 Young dogs
 Dolicocephalic breeds
 Aspergillus – penicillin
 Immunocompromised individuals


Nasal aspergillosis dogs clincical signs

 Chronic nasal discharge
 Haemorrhage
 Depigmentation of the nose
 Pain around muzzle
 Pain on eating


Nasal aspergillosis dogs differential diagnosis and diagnosis

Diff diagnosis:
 Nasal tumour
 Idiopathic rhinitis
 Foreign body
 Trauma

 Radiography
 Serology
 Fungal culture
 Exclusion of other diseases


Nasal aspergillosis dogs treatment

 Systemic antifungals
 Topical antifungals
 Surgery to remove affected turbinates


What to rememebr when testing dogs for resp disease?

Often animals will test negative for everything. This is because it is being caused by a pathogen we don’t get know about