Picoronaviruses and Calciviruses Flashcards
calcivirus general properties
- pos ss RNA
- cause acute dx may persist but dx will be acute
- non enveloped
calciviruses replication
- can come in w/ mrna that can be instantly translated
important picoronaviruses
- foot-and-moutn dx
- swine vesicular dx
- Seneca valley virus
- enterovirus encephalomyelitis of pigs
- avain encephalomyelitis
picoronaviruses general properties
- pos ss RNA
- cause acute dx may persist but dx will be acute
- non enveloped
- small virus
- 6 genera, many dnt cause significant dx
picoronavirus replicatoin
- can come in w/ mrna that can be instantly translated
important calciviruses
- vesicular exanthema of swine
- feline calcivirus
- rabbit hemorrhagic dx virus
foot and mouth dx general characteristics
- highly contagious
- 7 serovars w/ many serotypes and no cross-protection btwn them
- v stable
- REPORTABLE
foot-and-mount dx affects who
- cloven-hoofed animals (pigs, cows, sheep)
foot and mouth dx location
- scattered across world, places have this as endemic dx
- NOT in us
economic effects foot and mouth dx direct costs
- loss income farmers and producers
- costs to eradicate
- can cost billions
economic effects foot and mouth dx indirect costs
- meat export shut down
- livestock exports shutdown
- tourism
- consumer fear (although no actual risk ot us if we eat animals infected with this)
concerns regarding foot and mouth dx
- can be Brough into country on suitcase and this is endemic in countries on our watch list so need to be v careful
ways to handle foot and mouth
- slaughter all potential carrires
- South America control in face of endemic situation w/ vac and keep it contained this may be better way to go
foot and mouth dx transmission
- resp aerosols
- feeding of infected animal products
- mechanical transmission (boots, hands ect.)
- artificial insemination
- contaminated biologicals (hormones)
foot and mouth dx infects what
infects oral mucosa
epidemiological role sheep and goats foot and mouth dx
- maintanence
foot and mouth disease virus persists in what sheep and voats
- pharyngeal tissue (4-6 months)
epidemiological role pigs foot and mouth dx
- amplifiers
foot and mouth dx virus persists in what in pigs
no viral persistence
epidemiological role cattle foot and mouth dx
indicators
foot and mouth dx virus persists in what in cattle
pharyngeal tissue 6-24 months
foot in mouth dx virus pathogenesis
- aerosolized fmdv -> primary infection of pharyngeal epithelial tissues -> spread to regional lns -> viremia -> spread to secondary virus replication sites in cornfield epithelia -> skin, tongue, mouth -> vesiculation -> release large quantities of virus from vesicular fluid into saliva and envionrment
foot and mouth dx transmssibility
all will get infected in a population, this spreads v fast then virus = secreted 24hrs b4 signs start to appear
foot and mouth dx incubation length
short
foot and mouth morbidity and mortablity
- morbidity= 100% in susceptible pop
- mortality is low
foot and mouth dx recovery
recovery w/ development of neutralizing antibodies but impact on production animals = long lasting
foot and mouth dx virus excretion
- found in all secretions and excretions of infected animals (ruptured vesicles on feet, saliva/ nasal discharge, mouth vesicles, breath, desquamated skin, urine/ feces/ vaginal discharge/ aborted fetuses/ embryo washings, milk, semen)
foot and mouth dx general signs
- vesicles and erosions mouth, nares, muzzle/ snout, feet, teat
- excessive salivation (bc ulcers in mouth)
- lameness, reluctance to move (vesicles in interdigital space)
cattle foot and mouth dx addition signs
- drop in milk yield (before other signs)
- oral lesions -> drooling and salivation
- hoof lesions = in interdigital space
- teat lesions
pigs foot and mouth dx clinical signs
- lameness (usually severe on hard floors, less so on pasture)
- death in unweaned piglets bc myocarditis
sheep foot and mouth dx clinical signs
- mild
- lameness
- death young lambs bc myocarditis
- bc signs mild w/ hard to find lesions sheep aren’t animals that make you find foot and mouth but they are ones you check once you find in cows/ pigs ect.
drooling cattle means what
- can be foot and mouth but can be a lot of things so dont jump to that but do check for vesicles
pig foot and mouth necropsy
- piglets focal areas myocarditis -> tiger striping
diagnosis foot and mouth dx
- clinical signs
- virus isolation and id
- detection antigen or nucleic acid
- complement fixation
- ELISA and virus neutralization
- REPORTABLE
- LAB SAMPLES SENT UNDER SECURE CONDITIONS TO AUTHORIZED LAB
differential diagnosis vesicular dx pigs
- vesicular stomatitis
- swine vesicular dx
- Seneca valley virus
- foot rot
- chemical and thermal burns
differential diagnosis vesicular dx cattle
- foot and mouth dx
- vsv
- infectious bovine rhinotracheitis
- bovine viral d+
- malignant catarrhal fever
- blue tongue
prevention and control foot and mouth dx
- infected or suspected or known in contact animals slaughtered
- ring vac around infected farm (with correct serotype)
- strict control movement humans and animals from infected premises
- disinfection and decontamination
foot and mouth dx vac
- prevents dx not infeciton
- trade restrictions if vac used
- annual vac required
foot and mouth dx control govenerment
- usda import regulations
- state and federal planning and training exercises
swine vesicular dx cause
- an enterovirus
swine vesicular dx found where
- endemic in many countries in asia
- REPORTABLE DX
clinical signs swine vesicular dx
- indistinguishable from signs of food and mouth dx
swine vesicular dx general characteristics
- fecal oral spread
- very stable virus, potentially present in dried meat products
- picoronavirus
swine vesicular dx excreted when
- prior to appearance of clinical signs
swine vesicular dx control
- similar measures to foot and mouth
seneca valley virus what type
- picornavirus
seneca valley virus affects who
pigs
seneca valley virus sings
- clinical signs indistinguishable from those of foot and mouth
- acute lamnesness
- vesicular lesions on coronary barn and snouth
- associated with piglet neonatal death
seneca valley virus transmission
- direct via fecal oral and resp
seneca Vally virus found where
- us
- canada
seneca valley virus diagnosis
- rt pcr
- virus isolation
- ELISA
seneca valley virus control
- new dx so not much yet
- good idea to report just to be safe bc its new but not technically a reportable dx
reportable picoronaviruses
- foot and mouth dx
- swine vesicular dx
- enterovirus encephalomyelitis of pigs (teschen dx)
enterovirus encephalomyelitis of pigs type virus
- picoronavirus
enterovirus encephalomyeleitis of pigs causes what in who
- neuro dx in pigs mild in US
- teschen dx in Europe
Teichen dx vs enterovirus encephalomyelitis of pigs
- both caused by enterovirus of pigs
- enterovirus encephalomyelitis of pigs in us, cause mild dx: d+, pericarditis, occasional abortion
- teschen dx in Europe = serious neuro dx
porcine enterovirus spread
- endemic in almost all swine herds
porcine enterovirus vac
- rapidly mutating so hard to vac against
encephalomyelitis virus pathogenesis
- ingestion virus by susceptible host -> replicate in intestine ->
1. spread to regional ln -> viremia -> spread to cns -> clinical signs encephalomyelitis
2. excretion of large quantities of virus in feces -> persistence of virus in environment -> ingestion of virus by susceptible host
avian encephalomyelitis aka
epidemic tremor
avian encephalomyelitis what type virus
- picocornavirus
avain encephalomyelitis causes what in who
- neuro dx young chickens, pheasants, quail, and turkeys
avain encephalomyeleitis distribution
worldwide
avian encephalomyelitis morbidity/ mortality
- high morbidity and mortality when AE introduced into susceptible flock
avain encephalomyeleitis transmission
- fecal oral
- vertical transmission
avain encephalomyelitis clinical features
- dec egg production
- neurons dx young chicks 1-21 days old (ataxia ->can’t eat or drink; tremors of head and neck)
- embryos fail to hatch
avain encephalomyelitis diagnosis
- clinical signs
- direct if assays
- virus isolation in cell culture or chick embryos
avian encephalomyelitis must differentiate from
Newcastle
avian encephalomyelitis control
- removal of infected birds
- vac breeding stocks
avian encephalomyeleitis affects who
- dx of chicks not really affect adults
caliciviridae general characteristics
- non enveloped
- small viurses
- pos sense rna genome
caliciviridae genera
- vesiviruses (feline calisi)
- lagoviruses (rabbit hemorrhagic dx)
major cause respiratory dx in cats
feline calcivirus = responsible for 40% cases in upper respiratory tract dx (other main cause = feline herpes virus)
feline calcivirus general
- many diff strains differ in virulence
- calcivirus
- stable in humid environments
feline calcivirus morbidity vs mortality
- high morbidity and low mortality
- pt of feline resp dx complex
- one of most common viral pathogens of cats
feline calcivirus carriers
cats can become carriers of fcv
feline calcivirus distinguishing
virulent isolates can’t currently be distinguished from non-virulent isolates by any diagnostic test
feline calcivirus transmission
- must be cautions w/ hygiene bc very easy for kittens to pick this up can even come into office for vac and end up picking up this virus
- ## aerosol and fomites
clinical signs feline calcivirus transmission
- mild conjunctivitis
- sneezing- rhinitis
- ulceration of tongue palate and nasal philtrum
- rarely more severe dx pneumonia
- infected cats shed large amounts virus for up to 3 weeks
carriers of feline calcivirus
cats with chronic gingivostomatitis
diagnosis of feline calcivirus
- clinical presentation
- virus isolation
- direct immunofluorescence (only test in shelter if trying to control large group of animals)
feline calcivirus control
- vac protection from dx not infeciton; significant rate vac failure; vac animals can be chronic carriers
- isolation/ hygiene ect.
virulent systemic feline calcivirus general info
- rare dramatic consequence FCV infeciton
- high morbidity high mortality
virulent systemic feline calcivirus clinical signs
- high fever *
- facial and limb edema*
- oral ulcers
- nasal and ocular discharge
- skin sores/ ulcers (footpads)
- multiorgan dysfx*
- sudden death *
rabbit hemorrhagic dx virus type
- calcivirus
- REPORTABLE
- virus very stable in environment
rabbit hemorrhagic dx contagious
highly contagious
rabbit hemorrhagic dx -> what in who
- peracute hemorrhagic dx (rabbits drop dead)
- wild rabbits in US not susceptible (not susceptible in aus either)
- affects European and domestic rabbits
- affects rabbits older than 40-50 days
rabbit hemorrhagic dx geographic distribution
- endemic china, Korea, Europe, cuba, aus, nz
- sporadic outbreaks in us REPORTABLE
rabbit hemorrhagic dx clinical signs
- fever
- sudden death
- less common: neuro, dyspnea, bloody nasal discharge
- 5-10% infected rabbits: chronic dx, jaundice, death 1-2 weeks
- all die from this eventually*
rabbit hemorrhagic dx pathology
- hepatic necrosis
- splenomegeally
- hemorrhage (organs)
- petechia (serosal membranes)
rabbit hemorrhagic dx transmission
- direct contact
- fomites
- recovered rabbits may be carriers (most die)
- morbidity 30-80%
rabbit hemorrhagic dx diagnosis
- reportable
- clinical signs and post-mortem findings
- hemagglutination
- pcr
- electron microscopy
- CANT GROW IN LABORATORY
Rabbit hemorrhagic disease control
- import controls on rabbit meat
- during outbreak infected and in-contact animals = euth
- vaccination (protect against dx not infection; not in us)
