Difference between revisions of "Respiratory Viral Infections"

From WikiVet English
Jump to navigation Jump to search
Line 89: Line 89:
  
 
===[[Sheep Pulmonary Adenomatosis]]===
 
===[[Sheep Pulmonary Adenomatosis]]===
 
*See [[Lungs Hyperplastic and Neoplastic - Pathology#Sheep pulmonary adenomatosis (SPA/ Jaagsiekte)|neoplasia]]
 
  
 
==In Goats==
 
==In Goats==

Revision as of 12:14, 30 June 2010


WikiPathWikiPath Banner.png
()Map CARDIORESPIRATORY SYSTEM (Map)
RESPIRATORY SYSTEM INFLAMMATION



In general

  • Some viruses are thought to induce modifications of the pulmonary defences by:
    • Damaging the upper respiratory tract, thereby facilitating bacterial attachment and colonisation, with reduced mucociliary clearance
    • Decreasing surfactant levels by destroying Type 2 pneumonocytes
    • Impairing the phagocytic ability of alveolar macrophages


In Dogs

Canine Distemper Virus

Canine Parainfluenza - 2

Infectious canine tracheitis

Canine Adenovirus 1

Canine Adenovirus 2

Canine Herpesvirus 1

Canine Respiratory Coronavirus

In Cats

Feline viral rhinotracheitis

Feline Calicivirus

In Horses

Equine respiratory viruses Concept Map (Courtesy of B. Stanikova)

Equine rhinovirus

Equine influenza

Equine Rhinopneumonitis

Equine Viral Arteritis

Equine Adenovirus

African Horse Sickness

Hendra Virus

In Cattle

Infectious bovine rhinotracheitis (IBR)

Bovine Parainfluenza - 3

Bovine adenovirus

Bovine Respiratory Syncytial Virus

Bovine rhinovirus

In Sheep

Maedi - Visna

Parainfluenza -3


Sheep Pulmonary Adenomatosis

In Goats

Caprine Arthritis-Encephalitis (CAE)

  • Caused by retrovirus (lentivirus) similar to Maedi Visna in sheep described above
  • Two forms:
    • Non-suppurative leukoencephalomyelitis in young goats and kids
    • Chronic, non-suppurative arthritis-synovitis in adult goats
  • Also causes interstitial pneumonia which tends to be obscured by other clinical signs
  • Gross pathology:
    • Mainly caudal lobes
    • Lungs are firm, grey-pink with grey-white focal lesions on cut surface
  • Micro pathology:
    • Thickened alveolar wall
    • Lymphocyte infiltration and type II pneumocyte hyperplasia
  • Can be confused with or coexisting with Parasitic pneumonia


In Pigs

Inclusion body rhinitis

Inclusion body rhinitis (Image sourced from Bristol Biomed Image Archive with permission)
  • Herpesviridae, porcine cytomegalovirus
  • Disease of suckling piglets 1-5 wks of age
  • Clinical signs: those associated with acute/subacute rhinitis (ie: serous nasal discharge, progressing to catarrhal or purulent discharge with time and secondary bacterial infections; sneezing; pyrexia), fever in young piglets (3-8wks old)
  • May progress to sinusitis, otitis media or pneumonia
  • Morbitity high, mortality low
  • Gross pathology - catarrhal discharge becoming purulent (secondary infection)
  • Histology:
    • Large basophilic intranuclear inclusion bodies in the surface and subepithelium of nasal and sinus glandular epithelium with lymphocytic infiltration of the mucosa
    • Bursting of nucleus with cell necrosis and sloughing of necrotic epithelium
  • Can develop viraemic stage, with inclusions and focal necrotising lesions in other organs eg: renal tubular epithelium
    • Usually younger piglets, can die during this phase
  • Usually resolves if uncomplicated but rhinitis may persist if secondary infection is present
  • May persist in pulmonary macrophages


Swine influenza

Porcine reproductive and respiratory syndrome

  • The syndrome is caused by a small enveloped RNA virus which belongs to the new Arteriviridae group
  • Replicates in and destroys macrophages and endothelial cells causing vasculitis -> viraemia -> virus shedding (nasal secretions, faeces)
  • Clinical signs: respiratory and reproductive failure, weaned pigs, tachypnoea, eyelid oedema, conjunctivitis
  • Moderate to severe interstitial pneumonia in the cranial lobe
  • Superimposed bacterial infections are common
  • Infectious disease in swine that emerged 10 years ago
  • Today, PRRS is endemic in many if not all the pig-producing countries


Postweaning multisystemic wasting syndrome (PMWS)


Porcine respiratory coronavirus