infect dz prev equine (Mallicote) Flashcards
1
Q
Vaccination guidelines
A
- vaccinate all the horses at the same time
- consider seasonal incidence of diseases
- follow manufacturer’s recommendations
- storage
- handling
- administration
2
Q
Record
A
administration and any reaction
-manufacturer warranty
3
Q
Vaccine efficacy
A
- Depends on type of vaccine and route of administration
- Individual response to vaccination may be affected by
- stress
- illness
- nutrition
- concurrent medications
- presence of colostral antibodies
4
Q
Vaccination of foals
A
- Foals usually require 3
- begin at 6 months old
- 6 weeks later give booster
- more shots 2 months later
- exceptions
- maternal interference
5
Q
Vaccine Titers
A
- no research to establish protective titers or challenge duration of immunity
- prolonging intervals may leave horses at risk of disease
- horses aren’t good at mounting immune responses
6
Q
Core vaccines def
A
prevent life-threatening dz
7
Q
Risk based vaccines
A
minimize or eliminate diseases that affect performance or herd health
8
Q
The core vaccines
A
- Tetanus
- Encephalidities
- EEE, WEE, West Nile virus
- Rabies
9
Q
Tetanus
about
A
- Clostridium tetani
- Neurologic disease
- present in intestines, manure, soil
- spores can exist for years in soil
- spores enter horse through wounds, lacerations, umbilicus
10
Q
Tetanus
Clinical signs
A
- stiff gait, facial muscle spasm, third eyelid prolapse
- Sawhorse stance
- Excessive response to external stimuli
- noise, touch
- Recumbency
11
Q
Tetanus
TX
A
- Sedatives, muscle relaxants
- tetanus antitoxin
- Penicillin or metronidazole
12
Q
Tetanus
Prevention
A
- Not contagious
- mortality: 80%
- All horses should be vaccinated annually
- tetanus toicoid vaccine, safe and good protection
- tetanus antitoxin for previously unvaccinated horses or neonates
- risk serum sickness
- Booster if open wound or sx procedure > 6 months since vaccine
13
Q
Tetanus
prevention foals
A
- begin at 6 months old if foal received colostrum from vaccinated mare
- first dose 4-6 mo
- booster 4-6 weeks later
- then @ 10-12 months
14
Q
Viral encephalomyelitis
A
- Diseases
- Eastern Equine Encephalomyelitis (alphavirus)
- more common than western
- Wester Equine Encephalomyelitis (alphavirus)
- Venezuelan Equine Encephalomyelitis (alphavirus)
- foreign animal dz
- West Nile Virus (flavivirus)
- seen first in 2001
- Eastern Equine Encephalomyelitis (alphavirus)
- Arboviruses
15
Q
Life cycle and host status of viral encephalomyelitises
A
- life cycle involves birds and mosquitos
- dead end hosts involves people and horses
16
Q
Mortality of viral encephalomyelitises
A
- EEE: 75-90%
- WEE: 19-50%
- VEE: 40-90%
- WNV: 30-35%
17
Q
WNV
CS
A
- muscle fasciculations: head/neck
- fever
- weakness/ataxia
- flaccid paralysis
- changes in mentation
- cranial nerve deficits
18
Q
EEE
Clinical signs
A
- neuro signs 5 days after exposure
- death 2-3 days later
- low grade fever first
- viremia for 2 days
- fever (up to 106 deg F)
- during viral proliferation
19
Q
EEE
Behavoir change
A
- irritable
- somnolent
- self-mutilation
- hyperesthesia
- hyperexcitable
- dec food/water consumpt
20
Q
EEE
Neuro signs
A
- dementia
- head-pressing
- leaning against wall
- compulsive walking
- blindness
- progressing to seizures
21
Q
Reportability encephalitis
A
- In Florida reportable
- can be a sign of increased risk
- public health dep does good surveillance of arboviruses
22
Q
summary encephalomyelitis
A
- EEE mortality: 75-95%
- EEE-cerebral cortex
- WNV mortality: 30-33%
- WNV - mind-hind Brain/Spinal cord
- vaccination = prevention
23
Q
EEE vaccination
A
- In Florida booster EEE/WEE every 4-6 months
- Naive horses
- 2 vaccinations 3-4 weeks apart
- Time to booster
- 1 month prior to peak mosquito season
24
Q
West Nile - vaccination
A
- Depends on vaccine used
- fort dodge innovator/Boehringer Ingelheim: 2 times a year
- merial recombitec - 1 time a year
- intervet PreveNile - 1 time a year
25
Q
EEE/WNV
vaccination Broodmares and foals
A
- Broodmares
- 30-60 days prior to foaling
- Foals
- begin vaccination series at 3-4 months
- maternal antibody interference
- subclinical exposure
- need 3 vaccines as foals
- begin vaccination series at 3-4 months
26
Q
Rabies
A
- Exposure of horses to potentially infected wildlife
- most common reservoir in FL is Racoons
- Horses = contact between people and wildlife
27
Q
Rabies public health concerns
A
- fatality is 100% in humans and animals
- cost of post-exposure treatment
- money, time, personnell
- number of people exposed
28
Q
Rabies
CS
A
- Rabies can look like anything
- incubation 2-9 weeks
- dumb form
- furious form
- ascending paralysis
29
Q
Rabies Vaccination
A
- Annual vaccine - Killed vax IM
- Foals
- begin at 6 months
- boost 4-6 weeks later
- boost at 10-12 mos
*DDX for the rabies case was EEE (but signs progressed too quickly-one day)
30
Q
Risk based vaccines
(Common)
A
- Influenza
- Equine herpesvirus (Rhinopneumonitis)
- Strangles
31
Q
Equine Influenza (about)
A
- Incubation period: 1-3 days
- Susceptible population < 3 years old
- Stressful conditions/travel
32
Q
Influenza
Clinical signs
A
- High fever (1-5 days)
- Cough (several weeks) and nasal d/c
- lethargy, depression
- reduced appetite
- muscle soreness
*rest is essential: 1 week off per day of fever (risk for secondary bact infections)
33
Q
Equine Influenza
vaccination
A
- vaccinate every 6-12 months (young traveling horses, show horses, sale horses, horses in training)
- decreases viral shedding
- 3 vaccine types
- traditional inactivated IM
- Modified live cold-adapted IN
- Canarypox vector vaccine IM
34
Q
Influenza
vaccination of foals and broodmares
A
- Broodmares
- give IM vaccine in last 30 days pregnancy
- vaccinate foals at 6 months of age
*Mallicote is ok with pushing flu and rhino to 7/8 months (prolonged immunity from dam)
35
Q
EHV
A
- EHV 1
- abortion, neonatal death, neurologic dz, respiratory dz
- fever and nasal d/c prior to neuro signs
- abortion, neonatal death, neurologic dz, respiratory dz
- EHV 4
- respiratory dz
*aka: rhinopneumonitis
36
Q
Equine herpesvirus - respiratory CS
A
- Nearly identical to influenza
- incubation time 2-10 days
- shed virus for 2-3 weeks
- most common in weanlings and yearlings
37
Q
How is EHV transmitted?
A
- respiratory route
- contaminated equiptment
- many horse carriers with no evidence of clinical signs
- stress can recrudesce
38
Q
Prevention of respiratory EHV
A
- vaccination decreases shedding of virus and severity of clinical signs
- Foals and weanlings
- start between 4-6 months
- vaccinate 4 weeks later
- third dose at 10-12 months
- start between 4-6 months
- Yearlings
- every 6 months
39
Q
EHV abortion
A
- typically occurs 7-9 months gestation
40
Q
Vaccination of Broodmares EHV
A
- Pregnant mares
- booster at 5, 7, 9 months pregnancy to prevent abortion
- Vaccinate 30 days prior to foaling for colostral immunity
- EHV 1
- EHV 4
41
Q
EHV 1 Neurological dz
A
- usually happens after resp signs
- dog sitting common
- considered contagious
- ‘neurotropic’ strain has high mortality
- can look like anything
- vaccination does not prevent dz
- MLV vaccine may minimize clinical dz and reduce viral shedding
42
Q
Control of outbreaks - EHV
A
- Iso all new arrivals for 21 days
- disinfect transport vans
- Iso horses with fever: check 2x a day
- keep aborted material away from herd
- lost of virus in aborted material
- isolate mare
43
Q
Strangles
A
- streptococcus equi equi
- reportable dz in Florida
- variable between states
44
Q
Strangles
CS
A
- Fever (102-105)
- lymph node enlargement and abscessation
- purulent nasal discharge
- respiratory distress
- retropharyngeal lymph node enlargement
45
Q
Transmission strangles
A
- Transmission: ingestion or inhalation of infected d/c
- horse to horse contact
- fomites (humans)
- highly contagious
- High morbidity, low mortality
46
Q
Incubation of strangles
A
- incubation period 3-14 days
- isolate horses with a fever asap
- shedding of bacteria does not begin until 1-2 days after pyrexia onset
- Use PCR and culture of pharynx/GP to detect disease
47
Q
Strangles infectious for
A
- at least 4 weeks after clinical signs resolve
- nasal d/c
- guttural pouch is clear
- more testing may indicate sooner safe period but expensive
- after guttural pouch samples are negative
48
Q
Confirming strangles
A
- Nasal/pharyngeal culture
- supposedly gold standard
- PCR: nasal swab or nasal flush/guttural pouches (90$)
- recent outbreaks: three neg PCR to be released from quarantine
- ideal to sample back of airway instead of just nasal swab
- Serology for SeM protein
- helpful for confirming purpura or bastard strangles
- weak positive - repeat in 7-14 days
- mod positive - exposure in last 2-3 weeks and/or infection in last 6 mo to 2 yrs
- high positive - complications of S. equi infections or recent vaccination
49
Q
Hygiene in strangles outbreak
A
- protective clothing
- gloves, booties
- foot baths
- disinfect stables/transport vehicles
- rest pastures - 4 weeks (may be excessively long)
50
Q
Strangles vaccination
A
- not perfect, adverse side-effects
- use on farms previosly effected
- farms with young stock
- sale/show stables
51
Q
Types of strangles vaccines
A
- M-protein based given IM
- strepguard
- strepvaxII (2-3 initial series)
- Need to booster 1-2 times a year
- Can cause abscesses at injection site and purpura
- Start vaccination at 4-6 months of age
52
Q
Strangles IN vaccine
A
- Pinnacle IN (3 initial vaccines)
-
may be more effective
- won’t induce colostral immunity
- can cause abscesses
- start vaccination at 6-9 months of age
- Do this last or only
*Pinnacle will pay for testing if horse is sick after vaccine
53
Q
Strangles vaccine risks
A
- immune mediated purpura hemorrhagica
- mild form of the dz
- abscess formation
- no vaccination in face of dz => purpura hemorrhagica
54
Q
Regionally used vaccine
A
- Botulism
- KY, PA-broodmares
- Potomac Horse Fever
- Equine Viral Arteritis (EVA)
- Rotavirus
- Endemic farms
55
Q
Botulism
A
- Toxicoinfectious botulism
- shaker foal syndrome
- forage poisoning (round bale with rotten middle)
- Toxin blocks transmission of impulses in nerves
- weakness, dysphagia, death
- flaccid paralysis
- Most horses affected by types B and C
- Endemic areas
- kentucky, mid-Atlantic seaboard states
*very regional dz
56
Q
Botulism vaccination
A
- Equine vaccine for type B toxoid
- no cross protection
- type C toxoid not approved for horses
- Vaccination recommended in pregnant mares in endemic areas
- prevent disease in foals
- give last trimester
57
Q
Potomac Horse Fever
A
- Neorickettsia risticii (parasites in fresh water snails and mayflies)
- endemic to eastern US and CA
- seasonal: July-September
- Transmission through trematode parasites of fresh water snails
- horses eat caddis flies
58
Q
Potomac Horse Fever
CS
TX
A
- Clinical signs
- severe diarrhea, fever (102-107 deg F)
- Laminitis (secondary)
- Treatment
- oxytetracycline, supportive care
59
Q
PHF vaccination
A
- questionable efficacy
- lack of seroconversion
- vaccine is only 1 strain (multiple strains exist)
- Initial series: 2 doses 3-4 weeks apart
- Booster every 6-12 months
- Appears to lessen severity of disease
60
Q
Equine Viral Arteritis
A
- Abortion is main concern
- Transmission: respiratory / semen
- Diagnosis - EVA titers and virus iso
*ventral and limb edema, respiratory signs, vasculitis (causes the abortion)
61
Q
EVA Vaccination
A
- Used to control EVA outbreaks, to prevent transmission from carrier stallions to unaffected broodmares
- Seroconversion caused by vaccination may interfere with requirements for export of semen or stallions
- document negative blood test before vaccination
- Vaccine: modified life, approved for use in stallions and open mares
- Vaccinate colts 6-12 months of age
- seronegative mares if bred to infected stallion
62
Q
Rotavirus
A
- Coronavirus
- Most common cause of infectious diarrhea in foals
- CS
- profuse watery diarrhea, fever, lethargy
- highly contagious
63
Q
Rotavirus
TX
Prevention
A
- TX
- Supportive care
- Prevention
- vaccination of pregnant mares before foaling in endemic herds may provide some protection
64
Q
Lyme disease
A
- some practitioners use canine lyme vaccine in endemic areas
- some evidence of seroconversion
- off label
- DX and TX are challenging
65
Q
Leptospirosis
A
- associated with recurrent uveitis, kidney infections, abortion
- no evidence if vaccine will help/hurt in cases of ERU (equine recurrent uveitis)
- not currently labeled for pregnant mares
66
Q
Equine Infectious Anemia
A
- Retrovirus
- transmitted by biting flies or blood contaminated needles
- flies don’t harbor will be on mouthparts
- Acute:
- fever, depression, petechiation
- Chronic:
- icterus, anemia, dependent edema
67
Q
EIA control
A
- Coggins test (AGID) or ELISA
- control program instituted after test developed in 70s
- some asymptomatic carriers remain
- Need negative test q 6-12 months
- travel, show, heath certificates
- reportable in all states
- positives tests require euthanasia
68
Q
Piroplasmosis
A
- Tickborne
- Theileria equi (formerly Babesia equi)
- Babesia caballi
- Transmission
- tick-borne disease (Dermacentor nitens)
- mechanical vector transission
- US considered non-endemic
- no tick vectors except southern texas
- treated as FAD
- International events quarantine horses from endemic areas
69
Q
Piroplasmosis
CS
DX
A
- CS (mild or severe)
- chronic: weak, dec appetite
- Acute: fever, anemia, jaundice, hemogobinuria
- DX: cELISA
- all imports must be tested
