Strangles

Question 1

What age horse can stangles affect?

Answer 1

All foals, weanlings and adults

Question 2

Outline the characteristics of S. equi equi

Answer 2

G+ve
Not commensal
Highly infectious
Equine specific

Question 3

How is strangles transmitted?

Answer 3

Contact with nasal secretions/LN discharge

Contact with asymptomatic carriers

Question 4

How long does recovery from strangles take?

Answer 4

2-3 weeks

Question 5

How long does nasal shedding continue after strangles disease?

Answer 5

2-3 weeks

Question 6

How can strangles present clinically?

Answer 6

Acute
Atypical
Complications

Question 7

What are the clinical signs of acute/classic strangles?

Answer 7

Pyrexia, depression, inappetence
LN abscess
Dyspnoea/dysphagia 
Mucopurulent nasal discharge
Cough

Question 8

What are the clinical signs of atypical strangles?

Answer 8

Mild URT inflam
Slight nasal discharge
Cough Pyrexia
Limited lympadenopathy

Question 9

Why is atypical strangles potentially v dangerous?

Answer 9

Doesn’t look like normal strangles and is therefore not identified and isolation protocols put in place

Question 10

What are the possible complication of strangles?

Answer 10

Pupura haemorrhagica (bleeds from capillaries => red spots and oedema), anaemia

Abdominal abscess

GP empyema and chondroids

Horner’s sydrome, CNS abscess

Mammary gland abscess, agalactia

Tracheal compression

Myopathy

Question 11

How is strangles diagnosed?

Answer 11

Clinical signs

Increased WBC, fibrin

Isolation/detection of S equi from LN/nasopharynx/GP

Question 12

What is the most sensitive diagnostic test for strangles?

Answer 12

PCR

Question 13

What is the most sensitive sample to take for diagnosis of strangles?

Answer 13

GP lavage

Question 14

How are horses that have been exposure to strangles treated?

Answer 14

Penicillin until isolated from infected horse

Question 15

How are horses with early clinical signs of strangles treated?

Answer 15

Penicillin

Nursing, anti-pyretics, soft food

Question 16

How are horses with LN abscesses in strangles treated?

Answer 16

Poulticing and drainage of abscess

Nursing, anti-pyretics, soft food

Question 17

What are the most common complications of strangles?

Answer 17

GP empyema and chondroids

Abdominal abcesses

Question 18

How are abdominal abscesses in strangles cases diagnosed?

Answer 18

US

Rectal

Question 19

How are abdominal abscesses in strangles cases treated?

Answer 19

Long term ABs

Penicillin/TM/Rifampin

Question 20

How are GP empyema/chondroids diagnosed and treated?

Answer 20

Endoscopy/Rads
Drainage via pharyngeal openings
Surgical drainage
ABs

Question 21

How are carriers of strangles treated?

Answer 21

Endoscopic GP lavage
Topical AB (benzylpenicillin) in GP
Repeat lavage and PCR 2 weeks later

Question 22

How are strangles outbreaks managed?

Answer 22

Isolate premise
Isolate horses until 4 weeks after signs
No sharing of staff/equipment with infected horses
Detect and treat asympomatic carriers

Question 23

What methods of disinfectants are used in the management of strangles?

Answer 23

Phenolics for equipment

Iodophores or chlorhex for staff

Question 24

Is vaccination against strangles available?

Answer 24

Yes

Question 25

What are the DDx for strangles in foals and weanlings?

Answer 25

Rhodococcus equi | Parascaris equorum

Question 26

How is R equi transmitted?

Answer 26

Inhalation of soil/faeces

Question 27

Outline the pathophysiology of Rhooccus equi pneumona

Answer 27

Inhalation of contaminated dust => destruction of alveolar macrophages => pyogranulomatous response => bronchopneumonia with widespread abcesses

Question 28

What age horses does R equi affect?

Answer 28

Foals 1-6m

Question 29

What are the clinical signs of R equi pneumonia?

Answer 29

Anorexia, depression, pyrexic Dyspnoea, tachypnoea Cough

Question 30

How is R equi pneumonia diagnosed?

Answer 30

Increased fibrin and neutrophils Tracheal wash US, radiographs PME

Question 31

What other systems is commonly affected by R equi other than resp?

Answer 31

GIT

Question 32

What pathology can occur with intestinal R equi?

Answer 32

Ulcerative enterocolitis Mesenteric lympadenitis Abscess formation Peritonitis

Question 33

What are the clinical signs of R equi intestinal form?

Answer 33

Depression, pyrexic Diarrhoea Colic Weight loss, poor growth

Question 34

How is intestinal R equi diagnosed?

Answer 34

Hx and CS Increased neutrophils, fibrin, thrombosis PME

Question 35

How is R equi treated?

Answer 35

Clarithromycin or axthromycin AND rifampin | Treat until radiographic resolution of lesions and CBC and fibrinogen are normal 4-12 weeks

Question 36

How is R equi prevented with management?

Answer 36

``` Increased ventilation, dust free Avoid dirty pasture and overcrowding Rotate pasture to avoid grass destruction Collect manure Isolate sick foals ```

Question 37

How is R equi prevent by drugs?

Answer 37

Prophylatic hyperimmune plasma transfusion

Question 38

Is a vaccination available for R equi?

Answer 38

No

Question 39

How is parascaris equorum diagnosed and treated?

Answer 39

Faecal egg count | Anthelmintics

Question 40

What are the DDx for strangles in adults?

Answer 40

EVA | Equine rhinitis virus

Question 41

What kind of virus is EVA?

Answer 41

RNA arterivirus (NOTIFIABLE)

Question 42

How is EVA transmitted?

Answer 42

Venereal from stallions Contact with aborted foetus Direct contact with resp droplets

Question 43

What are the clinical signs of EVA?

Answer 43

``` No signs Pyrexia, anorexia Oedema Lacrimation, conjuctivitis Nasal discharge Coughing Abortions, stillbirth ```

Question 44

How is EVA diagnosed?

Answer 44

PCR of blood/nasal swabs/semen

Question 45

How is EVA treated?

Answer 45

Symptomatic only

Question 46

Is there a vaccination for EVA?

Answer 46

Yes - aterivac | Requires pre vaccination blood test to prove non-carrier status

Question 47

What should be done after a positive EVA test result?

Answer 47

``` Notifiable Stop all breeding Isolate and treat case Screen all horses on premise Test semen from all stallions Clean and disinfect Monitor semen +ve stallions for persistence and shedding ```

Question 48

What is EIPH?

Answer 48

Exercise-induced pulmonary haemorrhage

Question 49

Why does EIPH occur in the caudodorsal lung lobes?

Answer 49

Higher blood flow Displacement of diaphragm causes lower alveolar pressure Greatest mechanical forces in lungs

Question 50

What are the clinical signs of EIPH?

Answer 50

``` No signs Poor performance Sudden exercise limitation Epistaxis Atrial fibrillation ```

Question 51

How is EIPH diagnosed?

Answer 51

Endoscopy BAL Radiography

Question 52

How is EIPH treated?

Answer 52

Alter training to reduce episodes Dust free environment Furosemide Vasodilators