(RNA VIRUSES) Lesson 14: Caliciviridae Flashcards
General description of Caliciviridae
- cup-shaped depressions visible on
the surface of the virions in negative-contrast electron micrographs - Small, non-enveloped, single-stranded
RNA viruses with icosahedral symmetry - Replicate in the cytoplasm
- Stable in the environment
- associated with
a wide range of conditions including
respiratory disease, vesicular lesions, necrotizing hepatitis and gastroenteritis. - Transmission occurs directly or indirectly without vector involvement.
Caliciviruses derive their name from the
Latin word calix meaning
cup
Caliciviruses are visible on
the surface of the
virions
Caliciviruses replicate in the
cytoplasm
have been associated with
a wide range of conditions including
respiratory disease, vesicular lesions, necrotizing hepatitis and gastroenteritis
Caliciviruses
Caliciviruses have been associated with
a wide range of conditions including
respiratory disease
vesicular lesions
necrotizing hepatitis
gastroenteritis
Transmission of Caliciviruses
directly or indirectly without vector involvement
Mechanical transmission of rabbit haemorrhagic disease virus by
mosquitoes
and fleas
Mechanical transmission of this disease by mosquitoes
and fleas
rabbit haemorrhagic disease virus
Mechanical transmission of this disease by mosquitoes
and fleas
rabbit haemorrhagic disease virus
Natural disease not seen since 1956,
confined to USA.
Vesicular
exanthema of
swine (VES) virus
Acute,
contagious,
vesicular
disease,
clinically similar to foot-and-mouth disease.
Vesicular
exanthema of
swine (VES) virus
Believed to have resulted from feeding of
SMSV-infected sea lion and seal carcasses
in swil
Vesicular
exanthema of
swine (VES) virus
Causes VES when inoculated into pigs.
Cause of cutaneous vesicles and premature
parturition in pinnipeds
San Miguel sea
lion virus (SMSV)
Upper respiratory tract disease in cats,
occurs worldwide
Feline calicivirus
Geographical distribution of Feline calicivirus
Worldwide
Outbreaks with severe systemic form
occasionally described
Feline calicivirus
Acute, fatal disease of European rabbits.
Rabbit
haemorrhagic
disease virus
Physiological resistance in rabbits less than
two months of age
Rabbit
haemorrhagic
disease virus
Related but distinct from RHDV
European brown
hare syndrome
virus
Similar disease to RHD, hepatic necrosis
and diffuse generalized haemorrhaging.
High mortality rate.
European brown
hare syndrome
virus
Associated with diarrhoea on occasion
Canine calicivirus
an acute, highly contagious vesicular disease of pigs
Vesicular exanthema of swine (VES)
The disease was confined to the USA
Vesicular exanthema of swine (VES)
Geographical distribution of Vesicular exanthema of swine (VES)
USA
A vigorous eradication campaign, including the implementation of garbage
cooking laws, was successful. The last case was recorded in 1956 and the USA was declared free of the disease in 1959.
Vesicular exanthema of swine (VES)
a reservoir of the Vesicular exanthema of swine (VES) exists in __________
marine mammals
However, a reservoir of the virus exists in marine mammals (______________, was isolated from Californian sea lions showing signs of disease
including vesicles on the flippers and premature parturition).
San Miguel sea lion
virus [SMSV]
San Miguel sea lion
virus [SMSV], was isolated from
Californian sea lions
signs of disease of San Miguel sea lion
virus [SMSV]
vesicles on the flippers and premature parturition
Outbreak of this virus can arise through feeding meat from infected marine mammals
to pigs in uncooked swill. The virus then spread between pigs by direct and indirect contact.
Vesicular exanthema of swine (VES)
The incubation period for VES is about ________ hours and the course of the
disease approximately ______ weeks.
24–72 hours
one to two weeks
VES: Vesicles occur in the
oral cavity
tongue
lips
snout
interdigital spaces
coronary band
Affected pigs are pyrexic and acutely lame
Vesicular exanthema of swine (VES)
Affected pigs by VES are
pyrexic and acutely lame
VES: high morbidity low mortality
The disease is clinically indistinguishable from the other vesicular diseases of
pigs, namely foot-and-mouth disease, vesicular stomatitis and swine vesicular
disease
Vesicular exanthema of swine (VES)
VES: Samples rich in virus include
vesicular fluid and the overlying flap of epithelium
Diagnostic techniques of VES include
✓ ELISA and CFT for antigen detection
✓ immunoelectron microscopy and virus isolation in pig kidney cell lines
✓
identification by virus neutralization
✓ RT-PCR
for antigen detection
ELISA and CFT
virus isolation of Vesicular exanthema of swine (VES)
pig kidney cell lines
