Nidoviridales Flashcards
What does nidus mean?
nidus = nest (reffering to the nested set of subgenomic mRNA synthesis for the structural proteins)
Morphology
+ssRNA genome, helical capsid, enveloped & big
Resistance
good pH resistance (pH3-9), but heat labile
Replication strategy
Baltimore IV
Host specific?
yes, in vitro as well
CPEs
not characteristic (cell roundng & lysis)
Torovirus
zoonoses (gastroenteritis)
HA
varies (HEV)
Antigenic properties
- relatively good antigens
- cross-reactions within genera - serogroups (IF, ELISA)
Diagnosis
- direct
- indirect
direct:
-isolation (difficult) + IF
-clinical signs, IF, IEM
indirect:
-ELISA, IF (cross-reactions), VN, HAI
Genus:
-Coronavirus
(alpha-, beta- and gammacoronavirus)
-Torovirus
(-Arteriviridae - arteritis)
Alphacoronavirus:
What is TGE, who and how does it affect?
TGE = Porchine transmissible gastroenteritis virus
affect piglets - severe enteritis, diarrhea
+respiratory form
Alphacoronavirus:
What is ED?
Ed = Porchine epidemic diarrhea virus
Alphacoronavirus:
What is FIP, who and how does it affect?
FIP = Feline infectious peritonitis virus
it is an immunocomplex disease which comes in a
-wet form: ascites, peritonitis
-dry form: nephriris, uremia
Other examlpes of alphacoronaviruses
- CCV = canine coronavirus - enteritis, diarrhea
- human enteric coronavirus
Betacoronavirus:
What is BCV?
BCV = Bovine coronavirus - winter dysentery, calf diarrhea
Betacoronavirus:
What is HEV?
HEV = Porchine hemagglutinating encephalomyelitis virus
Betacoronavirus:
What is SARS?
-natural host?
SARS = Severe acute respiratory syndrome virus
human pneumonia-> decreased surfacant production
- atelectasia
Natural host: palm civet cat, bats
Other examlpes of betacoronaviruses
- MHV = Mouse hepetitis virus
- Canine respiratory coronavirus - kennel cought syndrome
- Human respiratory coronavirus
Gammacoronavirus:
What is IB?
IB = Avian infectious bronchitis
- > chichen: respiratory symptomes
- > hens: egg deformaties
- nephropathogen strains - nephrititis, gout
What does Turkey bluecomb disease cause?
enteritis, diarrhea, exiccosis, cyanosis
Other examlpes of gammacoronaviruses
Duck, Goose, Pigeon, Pheasant coronaviruses
Torovirus:
What does torus mean?
Torus = base of a column
Torovirus:
What is Berne virus?
Berne virus = foal gastroenteritis
Torovirus:
What is Breda virus?
Breda virus = calf gastroenteritis
Other examlpes of Toroviruses
Chichen, swine, human gastroenteritis
Arteriviridae:
morphology
+ssRNA genome, icosahedral capsid, enveloped, medium size
Arteriviridae:
resistance
weak (37°C, pH 6-8)
Arteriviridae:
replication
Baltimore IV, subgenomic mRNA synthesis
Arteriviridae:
CPEs
not characteristic
Arteriviridae:
transmission
aerogen, sexual
Arteriviridae:
antigenic properties
good antigens, no cross-reactions
Arteriviridae:
diagnosis
-direct
-indirect
- Direct: clinical signs, isolation (difficult), histopathology, IF, RT-PCR
- Indirect: VN, ELISA
Arteriviridae:
Genus
Arterivirus
Arteriviridae:
what does EAV mean, and what does it cause?
EAV = equine arteritis virus
- arteritis - edema, abortion, respiratory symptoms
- stallions may become persistently infected - carry the virus in the genital tract, shed the virus by the semen
Arteriviridae:
What does PRRS (SIRS) mean?
PRRS = prochine respiratory and reproductive syndrome
(SIRS = swine infertility and respiratory syndrome)
-> early abortion - infertility
-> respiratory symptoms - cyanosis (blue ear)
