Strep equi and PH

What is strangless?

A beta-hemolytic, gram-positive cocci that is host adapted and highly contagious

Primary bacterial pathogen

T/F strangles is a primary bacterial pathogen?

True

How is strep equi transmitted?

Direct contact in fomites

Common between young horses or a carrier anima

What are the C/S of Strep. equi?

Submandibular lymphadenopathy

Also biphasic fever, mucoid nasal discharge, reluctant to swallow, depression, extended head and neck

What lymph nodes can rupture in to the guttural pouch without us being able to tell externally?

Retropharyngeal

What should you do if you have guttural pouch empyema?

Need to flush it out as much as you can to prevent chondroid formation and persistent shedding

What is the best way to diagnose atypical stranles?

PCR (3x more sensitive than culture)

Where can horses get metastatic abscesses S. equi?

Abdominal or cranial

How do you test for metastatic abscess of S. equi?

SeM testing for IgG titer of 1:800ish or much higher

How do you treat S. equi subsp. equi?

Isolation

Warm, dry environment

Drainage of abscesses when possible with a hot pack

NSAID / flunixin meglumine as needed

If you are draining the guttural pouch abscesses what should you add?

3% penicillin gel but only if it is a persistent case

What is the biggest complication when there is trauma to the guttural pouch?

Dysphagia (hemorrhage is possible, but we can usually avoid vessels easily)

What are indications to give penicillin during Strep. equi infection?

Dyspnea, persistent fever, initial fever spike, purpura, myositis

What are the disadvantages of giving penicillin for Strep, equi?

Prolonged morbidity

Immunologic response

What is a common myth about giving penicillin during Strangles infections?

Will cause metastatic strangles

What causes fatal strangles (10% of cases)?

Metastatic disease

Purpura

Upper airway obstruction

How can you prevent strangles?

IM vaccine

What can happen after giving the Strangles vaccine?

Injection reaction

Sterile abscess

Purpura

When should you not give the Strangles?

If titers are >1,600

Why should you always have a tracheotomy kit ready?

Just in case the horse loses its airway during strangles

Why should you culture and PCR at 3-4 weeks post strangles treatment?

Convalescence is possible

What vaccine is best for strangles?

Live-attenuated intranasal vaccine

How do you prevent strangles other than vaccination?

Quarantine incoming horses for 21 days

Obtain 3 negative nasal swab cultures and PCR during quarantine

Guttural pouch lavage sample for PCR

How do you manage a strangles outbreak/

Isolate affected horses

Discontinue traffic on farm

Temp all horses BID

DIsinfect premises

Nasopharyngeal culture and PCR before release

What is strangles survival in the environment?

Not long unless it is cool and perfect conditions

What is purpura hemorrhagic?

Immune-mediated aseptic vasculitis (Type 3)

What does purpura hemorrhagica cause?

Immune complex deposition in vasculature

Neutrophilic vasculitis

High IgA to M protein ratio

What are the C/S of purpura hemorrhagica?

Painful limb swellings

DIscoloration of nose

Swelling of nares

Edema

Severe disease

What makes purpura hemorrhagic more common?

Having a high titer before getting the disease

How do you treat purpura hemorrhagica?

Local therapy with hydroRx, sweat and support bandages

Corticosteroids

Antibiotics

Dimethyl sulfoxide

NSAIDs