(RNA VIRUSES) Lesson 19: Paramyxoviridae Flashcards
order Mononegavirales includes viruses within the ff families
Paramyxoviridae
Filoviridae
Bornaviridae
Rhabdoviridae
Families Paramyxoviridae, Filoviridae, Bornaviridae, and Rhabdoviridae are ancestrally related as reflected by their common characteristics such as:
ENUMERATE
✔ single- stranded genome of negative-sense RNA
✔ replication strategy and gene order
✔ virion morphology that includes an envelope
Genus under Filoviridae
Ebolavirus
Marburgvirus
OIE emerging dse under Family Filoviridae (Genus Ebolavirus)
Zaire ebolavirus
species under Family Filoviridae (Genus Marburgvirus)
Lake Victoria marburgvirus
Genera under Family Paramyxoviridae
Henipavirus
Avulavirus
Respirovirus
Rubulavirus
Morbillivirus
OIE listed dse under Family Paramyxoviridae
1) APMV-1 - Avian paramyxovirus type 1 (Newcastle disease virus)
2) Nipah virus
3) Peste-des-petits-ruminants virus
4) Rinderpest virus
OIE emerging dse under Family Paramyxoviridae (Genus Henipavirus)
Hendra virus
How many serotypes are there in Family Paramyxoviridae (Genus Avulavirus)
11 serotypes
Newcastle disease virus also known as
APMV-1 (Avian paramyxovirus type 1)
OIE listed dse under Family Paramyxoviridae (Genus Morbillivirus)
1) Peste-des-petits-ruminants virus
2) Rinderpest virus
Viruses in this family cause a number of serious respiratory and/or systemic diseases of humans, animals, and birds.
Paramyxoviridae
General description of Paramyxoviridae
✔ cause a number of serious respiratory and/or systemic
diseases of humans, animals, and bird
✔ virions are enveloped, pleomorphic (filamentous or spherical; approximately 150
nm or more in diameter)
✔ contain a genome of linear, negative-sense, single- stranded RNA
✔ viral nucleocapsid (ND virus) has helical symmetry (herringbone pattern) and is
approximately 13–18 nm in diameter
✔ Paramyxoviridae are monotypic
pattern of the helical symmetry of the Paramyxoviridae nucleocapsid
herringbone pattern
glycoproteins present at the surface or spikes of the Paramyxoviridae
✔ Fusion protein
✔ Hemagglutinin
✔ Neuraminidase
Antigenic property of Genus Avulavirus
✔
Fusion (F) protein
✔ Haemagglutinin (HA)
protein
✔ Neuraminadase (NA)
protein
Antigenic property of Genus Morbillivirus
✔
Fusion (F) protein
✔ Haemagglutinin (HA)
protein
Antigenic property of Genus Pneumovirus
✓ Fusion (F) protein
network of rbc’s and viruses formed due to HA protein
Hemagglutination
In hemagglutination, network of rbc’s and viruses formed due to what protein?
Haemagglutinin (HA) protein
occurs when virus detaches from rbc’s due to neuraminadase (NA)
protein enzymes by breaking the contact of rbc and HA protein
Elution
Elution occurs when virus detaches from rbc’s due to ____________ enzymes by breaking the contact of rbc and HA protein
neuraminadase (NA)
protein
Paramyxoviridae are monotypic.
What does monotypic mean?
antibodies against one virus strain can neutralize all strains of the same species
is a highly contagious disease
of chickens that is characterized by respiratory distress, diarrhea, and neurological signs (tremors, wing or leg paresis, torticollis, circling, spasms), drop in egg production
Newcastle disease (ND)
Newcastle Disease is caused by what virus?
Avian paramyxovirus type 1 (APMV-1) or
Newcastle disease virus
First identified in Java, Indonesia (1926), and later in New Castle England
(1927)
Newcastle Disease
Other names of Newcastle Disease
✓ Ranikhet Disease
✓ Pseudofowl Pest, Avian
✓ Pneumoencephalitis
Severity of the Newcastle Disease is dependent upon the following
(1) age and immune status of
the birds
(2) the virulence of the strain of ND virus
are responsible for Avian paramyxovirus type 1 (APMV-1) or
Newcastle disease virus attachment to host cell and infection
✓ Fusion (F) proteins
✓ Hemagglutinin and Neuraminidase (HN)
Newcastle disease (ND) is characterized by
respiratory distress
diarrhea
neurological signs
drop in egg production
Three Strain/Pathotype of Newcastle Disease
Lentogenic (Avirulent)
Mesogenic (Moderately virulent)
Velogenic (Highly virulent)
Virulence of Lentogenic (Avirulent)
Low
Virulence of Mesogenic (Moderately virulent)
Moderate
Virulence of Velogenic
(Highly virulent)
High
Mortality of Lentogenic (Avirulent)
Negligible
Mortality of Mesogenic (Moderately virulent)
Upto 10%
Mortality of Velogenic (Highly virulent)
Upto 90%
Disease of Lentogenic (Avirulent)
Mild signs
Disease of Velogenic (Highly virulent)
Severe
Disease of Mesogenic (Moderately virulent)
Moderate
Forms of Newcastle Disease
a) Viscerotropic velogenic (Doyle’s form)
b) Neurotropic velogenic (Beach’s form)
c) Mesogenic form (Beaudette’s form)
d) Lentogenic form (Hitchner’s form)
high mortality, haemorrhagic
lesions in git, also called Asiatic or exotic ND
Viscerotropic velogenic (Doyle’s form)
Viscerotropic velogenic (Doyle’s form) also called
Asiatic or exotic ND
high mortality, respiratory &
neurological
Neurotropic velogenic (Beach’s form)
low mortality, respiratory &
neurological disease
Mesogenic form (Beaudette’s form)
mild respiratory disease
Lentogenic form (Hitchner’s form)
infects chickens, guinea fowls, turkeys, and a large number of species of domestic and wild birds
Newcastle disease virus
geographical distribution of Newcastle disease virus
worldwide
are less susceptible but may act as carriers to Newcastle disease virus
Sea birds
how Newcastle disease virus Cause minor zoonosis?
Infection in poultry handlers occurs when exposed to infected birds or live viral vaccines which may develop a self-limiting conjunctivitis
Infection of Newcastle disease virus in poultry handlers occurs when exposed to
infected birds or live viral vaccines
minor zoonosis of Newcastle disease virus may develop a
self-limiting conjunctivitis
is the most common route for transmission of NDV
Aerosol respiratory infection
NDV Infected birds begin to shed virus 2–3 days after exposure from their respiratory tracts and continue to shed virus for several
NDV is also readily spread by?
fomites
only this Strain/Pathotype of NDV produce gross lesions, but are not
pathognomonic, such as swelling of head, petechiae on the mucosa of proventriculus, ulceration of peyers patches, edema of interstitial tissue of neck
velogenic strains
NDV is now best accomplished using the ff Laboratory Diagnosis
a) PCR
b) sequence and/or nucleic acid hybridization analysis
lab diagnosis of NDV: use to distinguish whether the virus is a velogenic field strain or a live vaccine strain, and to differentiate it from avian influenza
sequence and/or nucleic acid hybridization analysis
Samples to be collected in NDV infected animal
Dead (post-mortem)
a) Spleen, lung, kidney
b) Intestine, Heart, brain, liver
live (antemortem)
a) Oro-nasal swab
b) Cloacal swab
c) Serum (antibody titer)
Laboratory tests for NDV
a) HA/HI test
b) RT-PCR
c) DNA sequencing
d) histological staining
e) nucleic acid hybridization
Cultivation of NDV can be done by inoculating to
a) embryonated chicken eggs (allantoic inoculation)
b) cell cultures with respiratory exudate or tissue suspensions
(spleen, lung, or brain)
death of embryo is observed within 24 hours with hemorrhages throughout the body, presence of NDV is confirmed by what lab tests
a) HA and HI test
b) RT-PCR
Control and Prevention of Newcastle Disease
Sanitary management
Medical prophylaxis
Vaccine strains under Lentogenic Pathotype for NDV
F (live attenuated)
Hitchner’s B1 (live attenuated)
La Sota (live attenuated or Inactivated)
V4
Vaccine strains under Mesogenic Pathotype for NDV
Mukteshwar (R2B) (live attenuated)
Roakin
Komarov (K)
live attenuated vaccine strains under Lentogenic Pathotype for NDV
F (live attenuated)
Hitchner’s B1 (live attenuated)
live attenuated or Inactivated vaccine strains under Lentogenic Pathotype for NDV
La Sota
live attenuated vaccine strains under Mesogenic Pathotype for NDV
Mukteshwar (R2B)