Cross Species Top 10 Reportable Diseases - Part 2 Flashcards
what diseases are involved in equine arboviral encephalomyelitis?
west nile virus, eastern equine encephalomyelitis, western equine encephalomyelitis, & venezuelan equine encephalitis
what is the classic case presentation of west nile virus in horses?
through out the USA & canada - fever, fasciculations of the face/neck, hyperesthesia, & colic
altered mentation, cranial nerve abnormalities, ataxia/paresis/paralysis
what is the classic case presentation of eastern equine encephalomyelitis?
east of the mississippi river & eastern canada - forebrain signs including head pressing/circling/seizures
highly pathogenic in horses with a mortality of 50-90%
what is the classic case presentation of western equine encephalomyelitis?
west of the mississippi river & western canada - characteristic head droop, less pathogenic/less active than the others
what is the classic case presentation of venezuelan equine encephalomyelitis?
altered mentation, cranial nerve abnormalities, ataxia/paresis/paralysis
highly pathogenic in horses - mortality of 50-90%
how are equine arboviral encephalomyelitis diseases diagnosed?
CSF fluid analysis
IgM capture ELISA for WNV
how are equine arboviral encephalomyelitis diseases treated?
supportive care - prevention includes vaccination & minimizing mosquito exposure
which of the equine arboviral encephalomyelitis diseases is the horse not a dead end host?
VEE - horses are viremic
T/F: equine arboviral encephalomyelitis diseases are pathogenic to humans
true
T/F: if a horse is recumbent due to an equine arboviral encephalomyelitis disease, it makes for a poor prognosis
true
how are equine arboviral encephalomyelitis diseases spread?
primarily spread by mosquitos during the summer transition season or the mosquito to bird to rodent cycle
what are the main differentials you should consider for equine arboviral encephalomyelitis diseases?
rabies
equine protozoal myeloencephalitis
neuroborreliosis
the stance & head droop this horse is displaying is typical for what equine arboviral encephalomyelitis disease?
WEE
what clinical signs are seen with rabies that make you consider it as a differential for equine arboviral encephalomyelitis diseases?
behavioral changes, progressive flaccid paralysis, distress/agitation, rolling (mistaken for colic), & self-inflicted wounds
what clinical signs are seen with EPM that make you consider it as a differential for equine arboviral encephalomyelitis diseases? what is the definitive host?
sarcocystis neurona, in north, south, & central america - ataxia, cranial nerve deficits, asymmetric muscle atrophy especially in the gluteal muscles
host - opossum, horses are infected orally from feed contaminated with opossum feces
what clinical signs are seen with neuroborreliosis that make you consider it as a differential for equine arboviral encephalomyelitis diseases? how is it treated?
borrelia burgdorferi from an infected tick that is most common in the northeast & upper midwest - neck stiffness, ataxia, vestibular deficits
treated with tetracyclines
what is another name for ornithosis?
chlamydiosis
what is the classic case presentation of chlamydiosis?
any parrot species, most frequent in cockatiels & budgies (possible in any species of bird, especially pigeons/doves) at any age - causes depression, anorexia, green/yellow diarrhea/urates, & sometimes conjunctivitis & upper respiratory signs in cockatiels
what is the etiology of chlamydiosis?
chlamydia psittaci
how is chlamydiosis diagnosed from a dead bird?
histopathology with the machiavello stain to demonstrate elementary bodies in hepatocytes or other cells
how is chlamydiosis diagnosed from a live bird?
blood, choanal/cloacal swab for serology/PCR
elevated WBC count, +/- elevated liver enzymes
radiographs - splenomegaly +/- hepatomegaly
how is chlamydiosis transmitted?
directly - aerosol or fecal/oral
why is chlamydiosis reportable?
zoonotic disease that causes flu-like symptoms in humans (parrot fever or psittacosis)
what is the prognosis of chlamydiosis?
good if caught early
how is chlamydiosis treated?
doxycycline (or tetracyclines, chloramphenicol) for 6 weeks & supportive care
what is the classic case presentation of avian newcastle disease?
affects ALL avian species - acute, highly contagious disease causing respiratory & neurologic signs (sometimes diarrhea) with virulence varying
high mortality with virulent forms - if confirmed in your country, trade restrictions are in place
what is the classic case presentation of highly pathogenic avian influenza/fowl plague?
low pathogenic - respiratory signs
high pathogenic - sudden death forms
HPAI: cyanosis, head edema, hemorrhages, greenish diarrhea, & high mortality!!!
ZOONOTIC!!
what is the mortality of salmonella pullorum?
nearly 100% mortality in young chickens & turkeys (2-3 weeks old) - in adult chickens, can see high mortality but no clinical signs
T/F: salmonella pullorum has been mostly eliminated from commercial flocks in north america
true
what is the classic case presentation of bovine johne’s disease?
alert with no fever, chronic intermittent diarrhea that is loose then pea soup like then watery, appetite starts off fine, milk production decreases with protein levels
weight loss, debilitation, emaciation, & submandibular & ventral edema
what is the number one sign of johne’s disease in sheep/goats?
weight loss
what is the classic case presentation of johne’s disease in sheep/goats?
weight loss, weakness, diarrhea isn’t common, wool break (sheds easily), submandibular edema without ventral edema, & decreased milk production
what is the etiology of johne’s disease?
mycobacterium avium subspecies paratuberculosis
what is seen on necropsy of a cow with johne’s?
thickened, corrugated intestines especially in the terminal ileum
enlarged edematous lymph nodes
what is seen on necropsy of sheep/goats with johne’s?
foci of caseation with calcification of the intestinal wall & lymph nodes
enlarged distal mesenteric lymph nodes
how is johne’s disease diagnosed?
culture is done for m. paratuberculosis from feces or a post mortem specimen - culture takes weeks & need to use a USDA approved lab
herd testing isn’t useful - wastes resources unless management is good
what treatment is used for johne’s disease?
no treatment - cull clinically affected animals
how is johne’s disease transmitted?
mostly fecal/oral - also colostrum, milk, intrauterine
when does shedding of johne’s disease begin?
begins prior to the onset of clinical signs
what is the number one mode of transmission of johne’s disease?
silent shedder cows
why is johne’s hard to deal with?
survives over a year in soil & even longer in water - isn’t killed by pasteurization either
T/F: johne’s disease is reportable in sheep & goats in all US states & reportable for cattle in some of them
true
what are the 3 forms of rabies?
- cerebral - furious
- brainstem - dumb
- paralytic - subset of dumb
what is the classic case presentation of the cerebral/furious form of rabies?
aggression, restlessness, howling, bellowing in cattle, excessive salivation, seizures, & tenesmus
what is the classic case presentation of the brainstem/dumb form of rabies?
somnolence, stupor, ataxia, opisthotonus, dropped jaw, dysphagia, excessive drooling, facial paralysis, & hypalgesia (decreased sensitivity to pain)
what is the classic case presentation of the paralytic form of rabies?
subset of the dumb form - ascending flaccid paralysis, monoparesis/plegia, truncal, limb, & perineal hyporeflexia/hypalgesia, priapism, urinary incontinence, self-mutilation, & profuse salivation
what is the etiology of rabies?
genus lyssavirus, family rhabdoviridae
how is rabies diagnosed?
direct/indirect fluorescent antibody stain of the brainstem & cerebellum shipped COLD!!
histopathology - variable, mononuclear infiltration, perivascular cuffing, lymphocytic foci, babes nodules (tight groups of glial cells), & negri bodies (intracytoplasmic inclusions - NOT PATHOGNOMONIC)
immunohistochemistry is more sensitive than histopathology
what does worldwide rabies prevention focus on?
focuses on controlling rabies in dogs - dog registration, stray control, reduction of contact between susceptible dogs through leash laws, dog movement control, & quarantine, mass immunization, & notification of suspected cases & euthanasia of dogs with clinical signs or dogs bitten by a rapid animal
what prevention of rabies is used in north america?
pet vaccination to limit virus circulation to wild reservoirs such as raccoons, bats, skunks, & foxes
1950’s pet vaccination laws resulted in a huge decrease in human rabies deaths from 100s to 1-2/year
minimizing pet-wildlife contact - not leaving pet food outside at night
how is rabies transmitted?
usually through saliva - bite wound
virus passes through neurons in a retrograde fashion causing initial hyperactivity of neurons with hyperesthesia/tremors & later neuronal death with flaccid paresis/hypalgesia
what animals are most commonly affected by rabies in canada?
raccoons, foxes, skunks, & bats
when is world rabies day?
september 28th lol
what is the SINGLE BEST REFERENCE on rabies for veterinarians?
compendium for rabies prevention and control, 2016
T/F: rabid dogs, mostly in africa, asia, & latin america, cause 99% of human rabies deaths worldwide
true
