Equine Vaccines

Factors for assessing risk

• Anticipated exposure/seasonality

• Environ. factors

• Geographic factors

• Signalment

• Overall health status of patient

Methods of giving vx in horses

IM or IN

Where are IM vx given?

Cervical is most common

What muscles should be avoided for IM injections?

Gluteal mm.

Alternate sites for IM injections

Pectorals, Semimembranosus/Semitendinosus mm.

Safety concerns for giving vx

• PE factors (fever?)

• Outbreak situation?

• Titers?

• Treatment of reactions

What do titers show in relation to vx?

Shows whether the horse already has some immune response to the disease, which can help determine how necessary the vx is (weigh cost and health benefits)

Efficacy concerns for vx

• Proper storage & admin.

• No vx is 100% effective

Common clinical signs of vx reactions

• Fever

• Neck stiffness/soreness

• Lethargy

• Anorexia

• Injection site abscess

Extreme clinical signs of vx reactions

Urticaria, abscess, myonecrosis

Myonecrosis

Clostridial disease which can be associated with vx in rare cases

Core vaccines

Protect from diseases that are endemic to a region, with potential public health significance, required by law

Core vx in horses

• EEE

• WEE

• Tetanus

• Rabies

• West Nile Virus

What type fo pathogen are EEE & WEE?

Viruses

What family are EEE & WEE in>

Togavirsu

Vector for EEE & WEE

Mosquitoes

What species amplifies EEE & WEE?

Birds

Clinical signs fo EEE & WEE

Neuro disease

• Fever

• Lethargy

  • “sleeping sickness”

• Mentation changes

• Blindness

• Recumbency

• Can be fatal

Is full recovery common from EEE/WEE?

No - rare

EEE/WEE vx

Killed vx given IM usually in a combo

Frequency of EEE/WEE vx

Annual, or every 6 mo. in high mosquito areas

What type fo pathogen is tetanus?

Bacteria - gram + & anaerobic

What is the specific pathogen for tetanus?

Clostridium tetani

Where is the tetanus pathogen found?

In the soil

Clinical signs of tetanus

Neuro disease

• STIFFNESS

• Sawhorse stance

• Lockjaw

• 3rd eyelid prolapse

• Hyper responsiveness (sound & light)

• Recumbency

• Resp. failure

• Death

What clinical sign of tetanus indicates a worse prognosis?

Recumbency

2 forms of tetanus vx

toxoid & antitoxin

Which vx type is the core vx for tetanus?

toxoid

Tetanus toxoid vx

Inactivated toxin (killed) given IM annually

When shoudl tetanus toxoid vx be boostered?

At times of wounds or surgery if not given in last 6 mo.

Purpose of tetanus antitoxin vx

Immediate protection for unvaccinated horses or treatment of disease

Action of tetanus antitoxin

Binds to neurotoxin

Risk of tetanus antitoxin

Risk of fatal liver disease (Theiler’s disease)

Rabies pathogen

virus - rhabdovirus

Is rabies zoonotic?

Yes

Is rabies reportable?

Yes

Incidence of rabies in horses

Reflects incidence in wildlife

Clinical signs of rabies

Neuro disease

• The great pretender - looks like a lot of different things

• Encephalitis

• Twitching

• Hypersensitivity

• Lose sense of feet & limbs

• Behavioral changes - obtundation or aggression

• Weakness, ataxia, shifting lameness

• Colic

• Hydrophobia

• 100% mortality

Rabies vx

Killed vx administered IM annually

Do horses require a certification to registration for rabies vx?

No

Who can give a rabies vx for horses?

Must be given by a DVM

West nile pathogen

Virus - flavivirus

West nile incidence in US

endemic (first diagnosed in ‘99)

What is west nile transmitted by?

mosquitoes

What species are carriers for west nile?

birds

What are species that are incidental hosts for west nile?

humans and horses

Clinical signs of west nile

Neuro disease

• Fever

• Lethargy

• Anorexia

• Facial (muzzle) and neck twitches

• Weakness, ataxia

• Paralysis/recumbency

Mortality rate for west nile

25-35%

Vx options for west nile

innovater/prestige; recombitek

Innovator/prestige west nile vx

Killed virus vx given IM annually, or every 6 months in high mosquito areas (TX)

Recombitek west nile vx

Major combo vx for core vx

Core EQ innovator (zoetis)

Core combo vx is ____ reaction free

99.7%

How is the core combo vx given?

IM

What is important to ask for when looking at vx hx?

Speific product/vx (there are multiple “3-way”/”4-way”, etc. vxs for horses)

3 most commonly given risk based vacines

• Influenza

• Rhinopneumonitis (equine herpes)

• Strangles

What other RBV should be given specifically in TX?

VEE

Other RBVs that can be given based on risk factors

• Potomac horse fever

• Rotavirus

• Botulism

• Equine viral

VEE

Same family and similar clinical signs to EEE/WEE

Is VEE reportable?

No

Is VEE a core vx?

No

Flu and Rhino pathogen

Viruses

Flu and Rhino incidence

Very common and highly contagious

Flu & Rhino transmission

aerosol - coughing, snorting, nasal discharge, shared water

Length of infection for flu & rhino

7 days to several weeks

Clinical signs of flu & rhino

URT

• Fever

• Cough

• nasal discharge

• lethargy

• anorexia

Prognosis for flu & rhino

good prognosis

Types of equine herpesvirus

• Respiratory - 1 & 4

• Reproductive - 1 & 4

• Neurological - 1

Clinical signs of neurological equine herpesvirus

• incoordination

• weakness

• urine dribbling

• 
  

Flu/rhino vx

Killed given IM or modified live given IN

How frequently is recommended for flu/rhino vx in high risk horses

every 3-6 months

hihg risk horses for flu/rhino

• Young horses

  • Travel/shows

EHV schedule for pregnant mares

Pneumabort vx given 5, 7, 9 months gestation (some people also give at 3 months)

Do teh flu/rhino vx protect against the neuro form?

No

Strangles pathogen

Highly contagious bacteria

Strangles transmission

Strangles vx

Killed given IM or modified live given IN

Some boarding facilities require what non-core vx?

strangles

When to avoid giving strangles vx?

• Outbreak

• IN same day as other IM vx due to aerosol live particles causing abscesses

Equine vx schedule

No standard vx schedule, follow AAEP guidelines