Difference between revisions of "Feline Herpesvirus 1"

From WikiVet English
Jump to navigation Jump to search
(13 intermediate revisions by 3 users not shown)
Line 1: Line 1:
−
{{OpenPagesTop}}
+
{{unfinished}}
−
== Introduction  ==
 
  
−
Feline Herpes virus ('''FHV-1''') causes an upper respiratory tract infection: '''Feline Viral Rhinotracheitis'''.
+
rarely causes skin infections
 +
====Pathogenesis====
 +
*Upper respiratory tract infection: Feline Viral Rhinotracheitis
 +
**Viruses and bacteria are involved in the complex
 +
** The most frequent aetiologic agent is FHV-1, and less frequently feline calicivirus and/or ''[[Chlamydophila psittaci]]''
 +
**All three agents infect URT respiratory epithelium, although FHV-1 has the highest affinity for this epithelium
 +
***Feline calicivirus more frequently infects the oral mucosa -> ulcerative stomatitis
 +
***C.psittaci more frequently infects the conjunctival epithelium -> chronic conjunctivitis
 +
**Infection of the respiratory epithelium by FHV-1 results in a typical neutrophilic rhinitis with intraepitheial intranuclear eosinophilic inclusion bodies, with expected clinical signs
 +
**Resolution of clinical signs usually occurs by 7-14 days
 +
**FHV-1 remains '''latent''' in the trigeminal ganglion, and can reactivate at times of stress: Can infect the cornea -> ulcerative keratitis
 +
**Occasional mortality in kitten or immunocompromised animals usually associated with secondary bacterial infection
 +
*Erosions can affect the bronchi, resulting in '''interstitial pneumonia'''
 +
*Most common cause of '''keratitis''' and '''corneal ulcers''' in cat and '''gummy eyes''' in kittens
 +
**Rupture is a particular risk
  
−
Viruses and bacteria are involved in the complex, with the most frequent aetiologic agent being FHV-1, and less frequently [[Feline Calicivirus|feline calicivirus]] and/or ''[[Chlamydophila psittaci]]''. All three agents infect URT respiratory epithelium, although FHV-1 has the highest affinity for this epithelium. Feline calicivirus more frequently infects the oral mucosa -> ulcerative stomatitis and ''C. felis'' more frequently infects the conjunctival epithelium -> chronic conjunctivitis. All three together will result in the disease complex 'cat flu'.
+
====Epidemiology====
 +
*Widespread
 +
*Serious infection
 +
*Latent infection can be reactivated on boarding
  
−
Infection of the respiratory epithelium by FHV-1 results in a typical neutrophilic rhinitis with intraepithelial intranuclear eosinophilic inclusion bodies, with expected clinical signs. Resolution of these clinical signs usually occurs by 7-14 days, however, FHV-1 remains '''latent''' in the trigeminal ganglion, and can reactivate at times of stress. It can infect the cornea - ulcerative keratitis. FHV- 1 is the most common cause of keratitis and corneal ulcers in cats and gummy eyes in kittens.
+
====Diagnosis====
 +
*'''Nasal swabs''' on first week of infection can be cultured for virus isolation
  
−
Occasional mortality can occur in the kitten or immunocompromised animals usually associated with secondary bacterial infections.
+
====Treatment====
 +
For keratitis with corneal ulcers:
 +
*Subcut omega interferon
 +
*Topical trifluorothymidine (thymidine analogue) on eyes
  
−
The virus is widespread and common. It can cause serious infections as well as latent infections which can be reactivated on boarding or at other periods of stress.
+
====Control====
 +
*Killed and live '''vaccines''' are available
 +
**Live vaccines have provoked symptoms in immunosuppressed kittens and are no longer used in the UK
  
−
== Clinical Signs  ==
+
===Feline viral rhinotracheitis===
  
−
Upper respiratory tract signs such as [[rhinitis]], [[tracheitis]] and [[sinusitis]] as well as keratitis and [[Corneal Ulceration - Dogs and Cats|corneal ulcers]]. The corneal ulcers intially have a '''dendritic''' appearence, which is considered pathognomic. In combination with other agents, will cause 'cat flu' which will include sneezing, coughing, gummy eyes, nasal discharge, dyspnoea and conjunctivitis.
+
*Caused by a [[Herpesviridae|herpesvirus]]
 +
*Tends to be more [[Nasal Cavity Inflammatory - Pathology#Infectious causes of rhinitis|rhinitis]] than [[Trachea Inflammatory - Pathology#Infectious causes of tracheitis|tracheitis]], may extend to [[Paranasal Sinuses Inflammatory - Pathology#Infectious causes of sinusitis|sinusitis]]
 +
*Feline herpesvirus -1
 +
**One of the causes of Feline viral rhinotracheitis
 +
***Viruses and bacteria are involved in the complex. The most frequent aetiologic agent is [[Herpesviridae|FHV-1]], and less frequently [[Caliciviridae|feline calicivirus]] and/or ''[[Chlamydophila psittaci]]'' (NB: previously called ''Chlamydia psittaci'' var felis)
 +
*All three agents infect URT respiratory epithelium, although FHV-1 has the highest affinity for this epithelium
 +
*Feline calicivirus more frequently infects the oral mucosa -> ulcerative stomatitis
 +
*''C.psittaci'' more frequently infects the conjunctival epithelium -> chronic conjunctivitis
 +
*Infection of the respiratory epithelium by FHV-1 results in a typical neutrophilic rhinitis with intraepitheial intranuclear eosinophilic [[Degenerations and Infiltrations - Pathology#Cellular Inclusions|inclusion bodies]]
 +
*Uncomplicated cases resolve in 2-3 weeks
 +
*FHV-1 remains latent in the trigeminal ganglion, and can reactivate at times of stress
 +
*Can infect the cornea -> ulcerative keratitis
 +
*Mortality may be high in young kittens, debilitated and immune-suppressed animals, usually associated with secondary bacterial infection.
  
−
== Diagnosis  ==
+
[[Category:Herpesviridae]][[Category:To_Do_-_Clinical/Viruses]][[Category:Cat]]
−
 
+
[[Category:Respiratory_Viral_Infections]]
−
Clinical signs and history are usually used as a presumptive diagnosis prior to definitive diagnosis via laboratory tests.
 
−
 
 
−
'''Nasal swabs''' on first week of infection can be cultured for virus isolation, plus a swab of the eye.
 
−
 
 
−
== Treatment  ==
 
−
 
 
−
For keratitis with corneal ulcers treat with subcutaneous omega interferon and give topical trifluorothymidine (thymidine analogue) on eyes.
 
−
 
 
−
== Control  ==
 
−
 
 
−
Killed and live '''[[vaccines]]''' are available. Live vaccines have provoked symptoms in immunosuppressed kittens and are no longer used in the UK.
 
−
 
 
−
== References  ==
 
−
 
 
−
Bridger, J and Ruseel, P, (2007) Virology Study Guide, Royal Veterinary College
 
−
 
 
−
Ettinger, S.J. and Feldman, E. C. (2000) Textbook of Veterinary Internal Medicine Diseases of the Dog and Cat Volume 2 (Fifth Edition), W.B. Saunders Company
 
−
 
 
−
Ettinger, S.J, Feldman, E.C. (2005) Textbook of Veterinary Internal Medicine (6th edition, volume 2), W.B. Saunders Company
 
−
 
 
−
Merck & Co (2008) The Merck Veterinary Manual (Eighth Edition), Merial
 
−
 
 
−
{{Learning
 
−
|powerpoints = [[E-Lecture:Feline Herpesvirus-1]]
 
−
|Vetstream = [https://www.vetstream.com/felis/Content/Disease/dis60212 Feline herpesvirus disease]
 
−
}}
 
−
 
 
−
 
 
−
{{review}}
 
−
 
 
−
{{OpenPages}}
 
−
 
 
−
[[Category:Herpesviridae]] [[Category:Expert_Review - Small Animal]] [[Category:Cat_Viruses]] [[Category:Respiratory_Diseases_-_Cat]] [[Category:Respiratory_Viral_Infections]]
 
−
[[Category:Hepatitis, Viral]]
 

Revision as of 12:20, 30 July 2010



rarely causes skin infections

Pathogenesis

  • Upper respiratory tract infection: Feline Viral Rhinotracheitis
    • Viruses and bacteria are involved in the complex
    • The most frequent aetiologic agent is FHV-1, and less frequently feline calicivirus and/or Chlamydophila psittaci
    • All three agents infect URT respiratory epithelium, although FHV-1 has the highest affinity for this epithelium
      • Feline calicivirus more frequently infects the oral mucosa -> ulcerative stomatitis
      • C.psittaci more frequently infects the conjunctival epithelium -> chronic conjunctivitis
    • Infection of the respiratory epithelium by FHV-1 results in a typical neutrophilic rhinitis with intraepitheial intranuclear eosinophilic inclusion bodies, with expected clinical signs
    • Resolution of clinical signs usually occurs by 7-14 days
    • FHV-1 remains latent in the trigeminal ganglion, and can reactivate at times of stress: Can infect the cornea -> ulcerative keratitis
    • Occasional mortality in kitten or immunocompromised animals usually associated with secondary bacterial infection
  • Erosions can affect the bronchi, resulting in interstitial pneumonia
  • Most common cause of keratitis and corneal ulcers in cat and gummy eyes in kittens
    • Rupture is a particular risk

Epidemiology

  • Widespread
  • Serious infection
  • Latent infection can be reactivated on boarding

Diagnosis

  • Nasal swabs on first week of infection can be cultured for virus isolation

Treatment

For keratitis with corneal ulcers:

  • Subcut omega interferon
  • Topical trifluorothymidine (thymidine analogue) on eyes

Control

  • Killed and live vaccines are available
    • Live vaccines have provoked symptoms in immunosuppressed kittens and are no longer used in the UK

Feline viral rhinotracheitis

  • Caused by a herpesvirus
  • Tends to be more rhinitis than tracheitis, may extend to sinusitis
  • Feline herpesvirus -1
    • One of the causes of Feline viral rhinotracheitis
  • All three agents infect URT respiratory epithelium, although FHV-1 has the highest affinity for this epithelium
  • Feline calicivirus more frequently infects the oral mucosa -> ulcerative stomatitis
  • C.psittaci more frequently infects the conjunctival epithelium -> chronic conjunctivitis
  • Infection of the respiratory epithelium by FHV-1 results in a typical neutrophilic rhinitis with intraepitheial intranuclear eosinophilic inclusion bodies
  • Uncomplicated cases resolve in 2-3 weeks
  • FHV-1 remains latent in the trigeminal ganglion, and can reactivate at times of stress
  • Can infect the cornea -> ulcerative keratitis
  • Mortality may be high in young kittens, debilitated and immune-suppressed animals, usually associated with secondary bacterial infection.