Cross Species Top 10 Reportable Diseases - Part 1 Flashcards
what species are affected by foot-and-mouth disease? what species are not?
affected - cattle, goats, sheep, & pigs
not affected - HORSES!!!!!
what is the classic case presentation of an animal with foot-and-mouth disease?
painful vesicles/erosions on tongue/muzzle/gums/teats/between claws/coronary bands, high fever, drooling thick sticky saliva with lip smacking, lameness, abortions, & fast spread between animals
T/F: situation determines what diagnostic test to use for potential cases of foot-and-mouth disease
true
what is the etiology of foot-and-mouth disease?
aphthovirus of the picornaviradae family with 7 serotypes
what tests are used to diagnose foot-and-mouth disease? what samples are submitted?
tests - ELISA, PCR, virus isolation, electron microscopy, or complement fixation
samples - vesicular fluid, epithelium, exudates, pharyngeal/esophageal fluid, milk, semen, & blood
approved labs do initial testing & special reference labs do confirmatory testing
what treatment is used for foot-and-mouth disease?
NONE - kill all affected/in contact
what preventative measures are used for foot-and-mouth disease?
euthanize all positive & in contact animals - bury or burn carcasses
maintain strict movement/entry requirements
quarantine +/- vaccination - killed vaccine provides 4-6 months immunity
thorough disinfection of premises/equipment - disinfectant with a pH less than 6 or greater than 9
what is the prognosis for animals with foot-and-mouth disease?
good for infected individuals
poor for overall herd health & economic outcome
guarded in neonates & nursing animals
_______-___-______ disease is one of the most contagious animal diseases known & is reportable worldwide due to its severe economic impact & production losses
foot-and-mouth
if you see these ulcers on a cow’s tongue that has signs of lameness, heavy drooling, and a high fever, what should you test for?
foot-and-mouth
what disease is the ‘evil twin’ to foot-and-mouth disease?
vesicular stomatitis
what species are affected by vesicular stomatitis? what environment & age group is more commonly implicated?
CATTLE & HORSES - occasionally swine, camelids, & rare in sheep/goats
warm humid areas in the western hemisphere - adult animals over 1 year of age
what is the classic case presentation of an animal with vesicular stomatitis?
fever, salivation, difficulty eating, vesicles/erosions/ulcers on mouth/lips/teats/coronary band, hyperemic skin or raised blanched areas in the mouth, variable morbidity with low mortality
what is the etiology of vesicular stomatitis?
rhabdoviridae family genus vesiculovirus with 2 serotypes - new jersey & indiana
how is vesicular stomatitis transmitted?
transmission by insects (sand/black flies, mosquitos) or direct contact with saliva, epithelium, exudates, or fomites
how is vesicular stomatitis diagnosed?
ELISA most common - used to identify the viral antigen or antibody
what treatment is used for vesicular stomatitis?
symptomatic care - soft feed, bedding, analgesia, & +/- antibiotics
what preventative measures are used for vesicular stomatitis?
QUARANTINE FARM!!! isolate affected animals, sanitation/disinfection, insect control, & vaccines
T/F: mortality from vesicular stomatitis is rare, but economic losses are significant
true
for an animal with vesicular stomatitis, what other diseases cannot be distinguished from it by clinical signs alone?
foot-and-mouth, swine vesicular disease, or vesicular exanthema of swine
what are the 8 big rule outs for vesicular diseases?
- bluetongue
- bovine papular stomatitis
- bovine viral diarrhea virus
- foot-and-mouth disease
- infectious bovine rhinotracheitis
- malignant catarrhal fever
- rinderpest
- vesicular stomatitis
T/F: pigs are the only animals affected by classical swine fever
true
what factors cause a varying severity of classical swine fever?
age - young animals are most severe with high mortality
immune status of the herd
strain of the virus
what is seen in the classic case presentation of the acute form of classical swine fever?
high fever > 105°F, anorexia, constipation followed by diarrhea, cyanosis, erythema, skin hemorrhages, staggering, incoordination, posterior paresis, seizures, & death within 1-3 weeks
some cases are asymptomatic and are inapparent carriers
what are some things that should make you suspect classical swine fever?
septicemia, high fever, incoordination, diarrhea, & death
history of feeding garbage, new/returning animals to the herd
NO response to treatment
cases on a nearby farm
what is seen on necropsy that is supportive of classical swine fever?
widespread hemorrhages
turkey egg kidneys with pinpoint hemorrhages
necrotic foci on the intestinal mucosa, larynx, & epiglottis
what test is used for surveillance of classical swine fever?
RT-PCR
what treatment is used for classical swine fever?
NONE! do not treat positive pigs!!!!
reportable - notify federal & state veterinarians!!!! quarantine farm until definitive diagnosis is made, & isolate suspected CSF-animals
how is classical swine fever prevented?
NEVER feed pigs undercooked garbage (swill) or pork products
quarantine newly purchased or returning animals for a minimum of 30 days
what are the main sources of infection for classical swine fever?
carrier pigs & feeding garbage
T/F: classical swine fever is DISTINGUISHABLE from african swine fever
false - clinically INDISTINGUISHABLE
if you see the pictured lesion on necropsy of a pig, what disease should you suspect?
classical swine fever
what is the morbidity/mortality of the acute form of classical swine fever?
100% morbidity/mortality
what is the ‘evil twin’ of classical swine fever?
african swine fever
what is the natural host of african swine fever? what clinical signs do they exhibit?
wart hogs - no clinical signs
how does african swine fever affect domestic pigs?
close contact between domestic pigs & wart hogs through infected ticks
what is the etiology of classical swine fever?
RNA pestivirus of family flaviviridae
what is the classical case presentation of african swine fever?
acute form - ear tip hyperemia, scleral hemorrhage, skin cyanosis, hemorrhagic intestines, high fever >105°F, 100% mortality
what is the etiology of african swine fever?
DNA virus genus asfivirus - only member of the family asfarviridae
how is a field diagnosis of african swine fever made? what samples are taken? where are they sent?
history & clinical signs - if suspected, report immediately
samples sent only to authorized state diagnostic lab via secure shipping
tonsils are the best sample - other options include kidney, spleen, lymph nodes, & whole EDTA blood
what diagnostic test can detect the onset of african swine fever prior to clinical signs?
PCR on tonsil scrapings
what is the treatment of african swine fever?
none - quarantine farm
slaughter all, burn, or bury carcasses
what is seen on necropsy of african swine fever?
a whole lot of hemorrhage
what prevention is used for african swine fever?
strict biosecurity & sanitation protocols
importation restrictions on pigs/pork products
never feeding pigs undercooked garbage (swill) or pork products
what is the vector that causes african swine fever leading to devastating economic impact?
soft ticks that inhabit wart hog burrows
what is the classic presentation of bovine spongiform encephalopathy?
animal older than 2 years old with an insidious onset of abnormal behaviors - aggression, apprehension, ataxia, tremors, low head carriage, weight loss, & reduced milk yield
what is the etiology of BSE?
transmissible spongiform encephalopathy that is caused by a misfolded version of a normal cell prion proteins
how is BSE tested for with surveillance screening? what about further definitive testing?
surveillance - ELISA test
definitive - send to a national veterinary services lab approved for confirmation
where can you find a list of approved labs where testing for BSE can be done?
national animal health laboratory network
what treatment is used for BSE?
none - euthanized
what prevention is used for BSE?
do not feed animal tissues/products to cattle
incineration of infected carcasses is the best method to destroy prions
test all downer cows for BSE
take great care in handling tissues
T/F: BSE is ALWAYS fatal
true
unlike scrapie, what clinical sign isn’t seen in BSE?
pruritus
how is BSE spread?
spread by ingestion - no genetic susceptibility is required
is BSE zoonotic? how?
YES!!!
linked to variant form of creutzfeldt-jakob disease in humans
how would you describe this histopathology lesion taken from a cow with BSE?
vacuolar/spongy appearance of gray matter
what is the best tissue sample that can be submitted for diagnosing BSE in a cow?
obex of the brain
what is the common signalment of animal affected by scrapie?
adult sheep > 2 years, black faced breeds in USA
seen in goats rarely
what is the classic case presentation of a sheep with scrapie?
pruritus - sheep rub their skin constantly, wool is scraped off, hypersensitivity reactions
progressive neurologic signs - head tremors, ataxia, bunny hopping, prancing, nibbling at legs & air
behavior changes - separation from the flock, hyperexcitable
weight loss with normal appetite
dead within weeks to months once clinical signs are present
what is the etiology of scrapie?
misfolded versions of normal cellular proteins - prions (PrPSC)
how is scrapie diagnosed? what test is the gold standard? what samples are taken? what tests are used for screening?
must detect prion proteins in tissues
IHC is gold standard - looking for vacuoles & plaques
samples - brain tissue most often obex & for atypical scrapie, the cerebellum, lymphoid tissue biopsy of the 3rd eyelid
western blot when tissues are autolyzed
ELISA for screening - brain & lymphatic tissue
how is scrapie treated?
no treatment - euthanasia
how is scrapie prevented?
great care in handling & transporting tissues
breed only genetically resistant sheep, do not feed ruminant proteins to sheep, maintain closed herd, euthanize positive sheep, & follow the eradicate scrape guidelines & US mandatory scrapie eradication program
carcasses - incineration or alkaline digestion
what is the incubation period of scrapie?
2-5 years
T/F: because prions are a normal cellular protein, there is no immune response in scrapie
true
what animals are affected by chronic wasting disease?
white tailed deer, mule deer, & elk
what is the classic case presentation of chronic wasting disease?
white tailed deer, mule deer, or elk - in adults older than 16 months
aspiration pneumonia due to esophageal dysfunction, weight loss, neurologic signs, behavior changes
what is the etiology of CWD? how is it diagnosed? what samples are taken for deer & elk?
misfolded versions of normal cellular prion proteins (PrPCWD)
detect the prions - ELISA for screening & confirmed with IHC or western blot
deer samples - brainstem/obex, lymphoid tissue, & retropharyngeal lymph nodes
elk samples - brainstem/obex & lymphoid tissues
what treatment is used for CWD?
none - euthanize
what prevention is used for CWD?
quarantine animals, test & cull animals, & disposal using incineration or approved disinfectants
T/F: for CWD, cooking doesn’t destroy prions from CWD
true
T/F: horizontal transmission plays a role through direct contact of an infected animal & the environment in CWD
true
what are the 3 types of EIA? which is the most common?
- inapparent - most common, no clinical signs
- acute - fever, lethargy, thrombocytopenia
- chronic - recurrent episodes of fever, anemia, weight loss, ventral edema, & petechiation
what is the etiology of EIA?
lentivirus from the retroviridae family
how is EIA diagnosed? how must testing be done?
coggins test - AGID or ELISA
must be performed at a USDA-approved lab & submitted by a licensed & federally accredited veterinarian
what treatment is used for EIA?
none - euthanize
what prevention is used for EIA?
euthanizing positive animals, regular testing, insect control
what are your options for a horse if they test positive for EIA?
can either live isolated at least 200 yards away from other horses or euthanized
what mandatory testing is required for EIA in horses?
all horses moved interstate or sold within a state must have tested negative for EIA within the last 12 months of the sale/move
how is EIA transmitted?
transmitted by biting insects or blood transfer
