Author, Donkey, Bureaucrats, Administrators
53,803
edits
Changes
Jump to navigation
Jump to search
no edit summary
Caused by ''[[Streptococcus equi subsp. equi]]''
*Epidemiology
**[[Respiratory Bacterial Infections - Pathology#Strangles|Strangles]] is a highly infectious disease of horses caused by ''Streptococcus equi'' subsp. ''equi''
**[[Respiratory Bacterial Infections - Pathology#In Horses|upper respiratory tract disease of horses]] with fever and abscessation of regional lymph nodes
**Cause rhinitis, [[Nasopharynx Inflammatory - Pathology|pharyngitis]], lymphadenitis and [[Muscles Inflammatory - Pathology#Abscesses|myositis]]
**Outbreaks in groups of young horses
**Transmitted via purulent exudate discharging from upper respiratory tract or from lymph nodes
**Chronic, carrier state can occur with bacteria im the guttural pouch
**A mild, atypical form can occur
**''S. equi'' shed for 4 weeks beyond clinical resolution
*Clinical signs
**Incubation period 3 to 6 days
**Fever, depression, anorexia
**Purulent nasal discharge
**Swollen, painful regional lymph nodes, especially submandibular
**Abscessation and rupture of lymph nodes
**Guttural pouch empyema
**100% morbidity; 5% mortality
**Death can occur from pneumonia, breathing difficulties from swollen lymph nodes or [[Muscles Degenerative - Pathology#Ischaemia|purpura haemorrhagica]](an immune-mediated disease)
**Bastard strangle may occasionally occur, with abscessaation in many organs of the body
**''S. equi'' may be involved in [[Bacterial skin infections - Pathology#Systemic bacterial infections|cutaneous lesions]]
*Diagnosis
**Clinical signs and history
**Mucoid colonies with beta-haemolysis
**Sugar fermentation allows differentiation of ''S. equi'' from ''S. zooepidemicus'' and ''S. equisimilis''
**PCR to detect asymptomatic carriers
*Treatment and control
**Penicillin administration to in-contact animals
**Isolation of affected animals
**Quarantne in-coming animals
**Avoid overcrowding and mixing different age groups
**Disinfection of equipment
*Gross pathology
**Initial bilateral nasal discharge, serous becoming purulent
**Catarrhal conjunctivitis may be present
*Less frequently, complications can occur as follows :
**Purulent inflammation may extent to [[Guttural Pouches Inflammatory - Pathology|guttural pouches]] or [[Lungs Inflammatory - Pathology#Infectious causes of pneumonia|lungs]], [[Paranasal Sinuses Inflammatory - Pathology#Infectious causes of sinusitis|sinusitis]]
**Bacteraemia with metastatic abscesses - most often to the mesenteric and mediastinal lymph nodes, less frequently, other organs such as [[Liver - Anatomy & Physiology|liver]], kidney and brain can be involved - '''Bastard strangles'''
**Retropharyngeal abscesses can rupture onto the skin of neck or into the [[Guttural Pouches Inflammatory - Pathology|guttural pouch]] resulting in '''guttural pouch empyema or chondroid formation''' - carrier state
**[[Muscles Degenerative - Pathology#Ischaemia|'''Purpura haemorrhagica''']]: an acute vasculitis causing urticaria and extensive oedema of ventrum, head and distal limbs
**[[Larynx Degenerative - Pathology#Laryngeal hemiplegia|Laryngeal hemiplegia]] due to enlarged retropharyngeal lymph nodes
**Compression of cranial nerves
*Interview with Professors Josh Slater and Ken Smith providing an interesting insight into the pathogenesis, prevalence and possible prevention of ''Streptococcus equi'' infections in horses - listen to [http://www.rvc.ac.uk/Review/Podcasts/RVC_Podcast_12.m4a Strangles podcast]
[[Category:Respiratory_Bacterial_Infections]]
[[Category:Respiratory_Disorders_-_Horse]]
[[Category:To_Do_-_Respiratory]]