Download RNA Viruses of Animals

RNA Viruses
of Animals
Viral Classification
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Taxonomy
 Order (-viridae)
 Family (-viridae)
 Subfamily (-virinae)
 Genus (-virus)
 Species
Group
 III (ds)
 IV (+ss)
 V (-ss)
RNA Virions
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Cytoplasm:
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Replication
Biosynthesis
Helical capsid
Most enveloped
with spikes
NA
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Double sense
Single sense (+ / -)
2 single sense (+)
Viral Entry into Cells
Group III: dsRNA
Reoviridae
REOVIRIDAE
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REO=Respiratory
Enteric Orphan Virus
Non-enveloped
Icosahedral
RNA ds
Segmented
Human Diseases
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Rotavirus
Coltivirus
Rotavirus
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World wide infection
Fecal-oral spread
Incubation: 1-3 days
Diarrhea
Children
Diagnosis
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ELISA
Latex Agglutination
Prevention
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Hygiene
Water sanitation
Coltivirus
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Colorado Tick
Fever
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Disease
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•
•
•
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Acute
Myalgia
Photophobia
Rash
Hemorrhage
Tick vector
Rodent reservoir
RNA ss (+); (-); & retro-
Group IV: +ssRNA
nonenveloped
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Picornavirus
Rhinovirus
 Enterovirus
 Hepatovirus
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Calicivirus
 Astrovirus
 Hepevirus
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Hepevirus
(formerly calcivirus)
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+ss RNA
nonenveloped
Icosahedral
Fecal-oral
Domestic pig
reservoir
Developing
countries/sanitation
Hepatitis E
(enteric hepatitis)
ASTROVIRIDAE
Astro = Star
 Nonenveloped
 +ssRNA
 7 Human Serotypes
 Diarrhea
 Treatment
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Supportive
CALICIVIRIDAE
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Calicus
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Cup shaped
Indentations
Non-enveloped
Icosahedral
Linear ss + RNA
Human Diseases
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Norwalk Virus
(Norovirus)
Calicivirus
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Norwalk Virus
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Summer diarrhea
Epidemic
Gastroenteritis
V/D
Institutions
ID virus in stool
90% of viral
diarrheas
PICORNAVIRIDAE
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Pico = small
Nonenveloped
Icosahedral
RNA + ss
Human Diseases
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Enterovirus
• Polio
• Coxsackie A , B
• ECHO
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Rhinovirus
Hepatovirus
Rhinovirus
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Common cold virus:
50%
Transmission: inhalation
Incubation: 1-3 days
Symptoms
 Sore throat
 Mucopurulent nasal
discharge
Complications
 predispose to
secondary bacterial
infections
Hepatovirus: Hepatitis A
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Infectious Hepatitis
Milder disease than
Hepatitis B
No chronic form
Fecal-oral
Incubation: 2-5 weeks
Virus excreted in stool
Resistant to
disinfection
Dx: IgM
Enterovirus
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Disease Groups
Poliovirus
 Coxsackie A, B
 Echovirus
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Fecal-oral
 Cytolytic
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GI mucosa
 Lymphatic tissue
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Echovirus
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ECHO=
 Enteric
 Cytopathic
 Human Orphan
Fecal-oral route
Disease
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Meningitis
Paralysis
URTI
Myocarditis
Fever
Rashes
Orchitis
Coxsackie A and B
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Fecal-oral
Disease
 Coxsackie A
• Skin Rashes
• Herpangina
• Mouth
• Pharynx
• Hand/Foot/Mouth
• Conjunctivitis
• +/- DM Type I cause
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Coxsackie B
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Myocarditis
Meningitis
URTI
Paralysis
Poliomyelitis
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3 serotypes (Type 1 disease)
Transmission: fecal-oral
Throat ->LN->Ileum->Blood-> CNS
Phases
 Asymptomatic: 90%
 Minor Polio
 Non-paralytic
 Paralytic: 2-3%, causes 75% of paralysis
Dx: virus in feces, secretions
Prevention: Vaccine
 Salk (IPV, killed)
 Sabin (OPV, modified live)
Poliovirus
Bulbar
Poliomyelitis
Post Polio syndrome
Group IV:+ssRNA
enveloped
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Togavirus
Flavivirus
Coronavirus
CORONAVIRIDAE
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Corona = crown
Enveloped
Helical
Linear RNA + ss
Respiratory droplet
Human Diseases
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Common cold
(20%)
SARS
Severe Acute Respiratory
Syndrome (SARS)
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Respiratory Droplet
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Direct
Indirect
2-10 day incubation
Cough->Pneumonia
Stable in environment
for days
Dx: PCR
Tx: supportive
Prevention
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avoid contact
disinfect
TOGAVIRIDAE
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Toga = coat
Spiked envelope
Icosahedral
Linear ss+RNA
~Arthropod vector
Human diseases
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Encephalitis
• (VEE, WEE, EEE)
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Rubella
Encephalitis: VEE, WEE, EEE
all
Rodent: VEE
Togavirus: Rubella
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Rubella
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German Measles
Respiratory Droplet
2-3 week incubation
Rash: 3 days
• Facial
• Spreads to body
• Changes hourly
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Complications
• Adults
• Arthritis
• Encephalitis
• Congenital defects
• Nervous
• Heart
• Blindness
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Prevention: MMR
Rubivirus
FLAVIVIRIDAE
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Flavus = yellow
Enveloped
Helical
Linear RNA ss +
Human Diseases
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Hepatitis
Encephalitis
Hemorrhagic Fever
Flavivirus
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Hepatitis C
• HCV
• Non A non B
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Endemic
Parental
• Blood
• Needles
• Organs
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6-8 week incubation
Mild form
Chronic
• Cancer
• Liver failure
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Dx:IgG, PCR
Tx: Interferon
Flaviviridae
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Hepatitis
 Yellow Fever
• Liver / GI
• Kidneys
• Heart
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Hepatitis G
• Acute
• Persistent
• Co-infection with
Hepatitis C
• Parental: blood
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Encephalitis
 Japanese Complex
 Russian
spring/summer
 St. Louis
• Acute
• Inflammatory
• Vector: mosquito
• 4-21 days
incubation
Flavivirus Encephalitis
Flavivirus
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West Nile Virus
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Acute
Febrile
Hemorrhagic
Vector: mosquito
3-14 days
incubation
Dx: IgM, ELISA
Tx: Supportive
Flavivirus: Dengue Fever
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Tropical
Aedes mosquito
Disease syndromes
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Breakbone fever
• Rash
• Myalgia
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Hemorrhagic fever
• Reinfection
• Hyperimmune
response
Group V: -ssRNA
enveloped, segmented
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Bunyvirus
Orthomyxovirus
Arenavirus
ARENAVIRIDAE
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Arenosus = sand (ribosomes)
Enveloped
Helical
Segmented linear ss- RNA
Rodent reservoir
Human Disease
 Hemorrhagic fever
• Old world
• Lassa
• Sabia
• Junin
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Lymphocytic
choriomenigitis (LCM)
• New world arenavirus
Arenavirus
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Hepatitis D
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Delta Agent
Defective
Incomplete ss RNA
• Viroid
• Co-infection with HepB
• Satellite virus
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Enveloped
Body fluid spread
BUNYAVIRIDAE
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Named after location
of first viral isolation
Spiked, enveloped
Helical
Circular ss-RNA
Human Disease
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Arborvirus
• Encephalitis
• Respiratory
• Hemorrhagic Fever
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Rodent
• Hanta Virus
Bunyavirus
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Hanta virus
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Adult Respiratory
Disease
1-3 weeks incubation
Transmission: deer
mice
Symptoms
• SOB
• N/V
• pain
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Tx: supportive
Prevention: rodent
control, disinfect
ORTHOMYXOVIRIDAE
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Myxo = mucus
Spiked envelope
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HA
• hemaggluttinin
• attach
• Antigen number
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NA
• neuraminidase
• through mucus
• antigen number
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Helical capsid
8 Segmented linear ssRNA
Human Diseases
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Influenza A
Influenza B
-ssRNA
Orthomyxovirus
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Influenza
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Range of symptoms from
mild to severe
Droplet
• Direct
• Indirect
1-3 days incubation
Reservoir: Humans
Treatments
• Vaccination
• Drugs
Complications
• Recombinant due to
segmented RNA
• Secondary bacterial
infections
• Viral super infection with
Adenovirus
Influenza Treatments
Inhibit Neuraminidase
Relenza (IN)
Tamiflu (PO)
Antigenic drift: HA/NA mutations
Antigenic shift: genetic reassortment
Influenza Pandemics
Group V: -ssRNA
enveloped, nonsegmented
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Paramyxovirus
 Morbillivirus
 Parainfluenza
 Rubella
 RSV
 Nipahavirus
Rhabdovirus
Filovirus
PARAMYXOVIRIDAE
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Similar to
Orthomyxoviruses
Spiked Envelope
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HA
NA
Fusion (F protein)
Helical
Segmented linear ss –
RNA
Human Diseases
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Respiratory
Epithelial
Paramyxovirus : Respiratory
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Parainfluenza
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4 types (HPIV)
Pediatric infection
Symptoms
• Fever
• Coryza
• Barking cough
(Croup)
• Airway obstruction
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Droplet
Tx: supportive
Paramyxovirus :Respiratory
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Respiratory Syncytial
Virus (RSV)
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Infants
Pneumonia
• lower airways
• Alveoli damaged
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Symptoms
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•
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Cold like
Fever
Coryza
Cough
Wheeze
Dsypnea
Droplet
Tx: supportive
Paramyxovirus: Epithelial
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Mumps
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Glandular (Parotiditis)
Droplet transmission
21 day incubation
Inflammation
Complications
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Encephalitis
Orchitis
Nephritis
Pancreatitis
Arthritis
IgM
Tx: symptomatic
Prevention: MMR
Rubulavirus
Mumps Pathogenesis
Paramyxovirus: Epithelial
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Measles (Rubeola)
 Epithelial mucosal
linings
• Skin -> rash
• Respiratory
• GI
 Complications
• Panencephalitis
• Conjunctivitis
 Droplet transmission
 10-12 days incubation
 Desquamation
 Highly infectious
 Tx: symptomatic
 Prevention: MMR
Morbillivirus
RHABDOVIRIDAE
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Rhabdo = rod like
Spiked, enveloped
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Hemagglutin
Helical
-ssRNA
Human Disease
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Vesicular Stomatitis
Rabies
Rhabdovirus
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Lyssa virus
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Rabies
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Encephalitis
Direct
3-8 weeks incubation
Replication
• Local
• CNS
• Salivary
• Reservoir
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Tx: IgG
Prevention: vaccination
Bats
K-9 / coyotes / foxes
Racoons
Skunks
• Clinical
• Furious
• Dumb
FILOVIRIDAE
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Filo = filamentous
Spiked, enveloped
Helical
Linear ss – RNA
Pleomorphic shape
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Filament, branched,
U-shape, Circular
Gp epithelial receptors
Human Disease
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Acute Hemorrhagic
fevers
• Marburg Virus
• Ebola Virus
Marburg
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Fruit bat/green monkey
Africa (Germany isolated
Body fluid spread
3-9 day incubation
Course
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Rash
Gi inflammation
Liver failure
Pancreatitis
Hemorrhageshock
MODSDeath
Ebola virus
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Africa
Direct contact
Acute hemorrhagic
fever
4-16 day incubation
Symptoms
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Fever
V/D
Rash
Hemorrhage from all
open body cavities
Death due to shock from
fluid and blood loss
RETROVIRIDAE
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Retro = reverse
RNA dependent DNA polymerase (RT)
Spiked envelope
polyhedral
2 linear +ssRNA (diploid virus)
Enzymes
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Reverse transcriptase
Protease
Integrase
Human Diseases
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Deltaretrovirus HTLV: leukemia
Lentivirus HIV: AIDS
Retroviridae
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Human T-Lymphocytic
Virus (HTLV-1)
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Adult T cell Leukemia
Aggressive Tumor
Latent
Infiltrates
• Skin
• brain
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Transmission
• Horizontal
• Blood
• Sexual Intercourse
• Vertical
• Breast milk
Retroviridae
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Human T-Lymphocytic
Virus (HTLV-2)
 B-Lymphocytes
 Hairy cell leukemia
• Slow growing
• Middle aged men
• Type of CLL
 Signs
• Bruising/bleeding
• Swollen LN
• Fatigue
• Fevers
Human Immunodeficiency Virus
Ecological Groups
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Arboviruses
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Arthropod borne
viruses
Transmitted by
•
•
•
•
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Insects
Mites
Ticks
Lice
Viral Families
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•
•
•
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Togavirus
Bunyaviridae
Rhabdovirus (some)
Arenavirus (some)
Reovirus (some)
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Oncoviruses
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Cancer causing
DNA related
Viral Families
•
•
•
•
•
Papovirus
Adenovirus
Parvovirus
Herpesvirus
Retrovirus
Zoonoses
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Disease that humans can acquire from
animals
Viral examples
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Marburg (monkeys)
Pox (cow pox, pseudo-cowpox, monkey pox)
Rabies (warm blooded mammals)
Influenza A
Lassa (rodents, bats)
Hanta virus: pulmonary (rodents)
Viral Vaccines
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Live / Attenuated
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Measles
Mumps
Rubella
Polio (oral)
Yellow Fever
VZV
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Killed / Viral
Protein
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Hepatitis A
Hepatitis B
Rabies
Polio (Salk)
Antiviral Chemotherapy
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Inhibits Viral DNA-dependent DNA polymerase
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Inhibits DNA replication and transcription
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Smallpox
Inhibits reverse transcriptase
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Influenza A
Inhibits translation of late mRNA
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Herpes
Interferes with penetration or viral uncoating
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Herpes
Aids
Inhibits Protein synthesis
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Genital Warts
Questions?