B&B RNA Viruses Flashcards
All (-) RNA viruses have
helical capsid
Which (+) RNA virus does not have an icosahedral capsid?
Corona (helical)
All helical RNA viruses are
enveloped
RNA viruses that are icosahedral can be
enveloped or naked
Which RNA virus is not ss?
Reovirus (ds)
Which RNA viruses do not replicate in cytoplasm?
Influenza and Retroviruses
Which RNA viruses are not linear?
BAD: Bunya, Arena and Delta (HDV)
Which RNA viruses have a segmented genome?
BOAR: Bunya, Orthomyxo, Arena, Reo
Caliciviruses
Non-enveloped, (+) ssRNA, linear, icosahedral
Norovirus (Norwalk Virus)
Viral gastroenteritis
2-3 days
Not inflammatory: no blood, mucus or fecal leukocytes
Hepeviruses
Non-enveloped, (+) ssRNA, linear, icosahedral
Hep E
Reoviruses
REO: Respiratory Enteric Orphan viruses
Non-enveloped, dsRNA, icosahedral
11 segments, linear
Contain RNA-dependent RNA polymerase
Coltivirus
Reovirus
Colorado Tick Fever
Fever, chills, myalgias, HA
Self-limited
Rotavirus
Reovirus
Gastroenteritis in kids
No blood, mucus, few/no fecal leukocytes
Live, attenuated vaccine given prior 6mo
Picornaviruses
PERCH: Poliovirus Echovirus Rhinovirus Coxsackie Virus Hep A
Picornaviruses
Non-enveloped, (+) ssRNA, linear, icosahedral
Synthesize large polyprotein that is cleaved to viral proteins
Which Picornavirus is not an enterovirus (fecal-oral transmission)?
Rhinovirus (Common Cold)
- Cannot survive in stomach (acid-labile)
- Transmitted directly via respiratory droplets
Inactivated Polio Vaccine
Salk
Injected so generates systemic antibody response (mostly IgG)
Live Polio Vaccine
Sabin
Local IgA antibody response
Echovirus
Picornavirus
Aseptic (viral) meningitis
90% of viral meningitis is caused by
Coxackie and Echoviruses
Hep A
Picornavirus
Non-enveloped
Which Coxsackie causes aseptic meningitis?
Both A & B
Hand, foot and mouth syndrome
Coxsackie A
Kids
Sore throat, oral vesicles
Rash: small lesions on hands, feet, buttocks
Herpangina
Coxsackie A Kids High fever, seizures Mouth blisters No rash Summer
Myocarditis, Pericarditis
Coxsackie B
Naked RNA Viruses
Calici (Norwalk)
Hepe (HEV)
Reo (Rota, Colti)
Picorna (PERCH)
Coronavirus
Enveloped, linear
only (+)ssRNA with helical capsid
Corona virus is a cause of
common cold
most common is rhinovirus
Which virus causes SARS?
Corona virus SARS: Up to one week prodome Fever, malaise, HA, Myalgias Cough, dyspnea Sometimes progressing to respiratory failure
Retroviruses
Enveloped, ssRNA, linear
Reverse Transcriptase
DNA replicates in nucleus
How is Human T-lymphotropic virus (HTLV) similar to HIV?
2 identical strands of (+) RNA
Enters CD4 T cells
Reverse transcribed to DNA
DNA product integrated into host cell genome
How is HTLV different from HIV?
T-cells proliferate and transform (rather than dying)
T-cell leukemia-lymphoma (Non-Hodgkins lymphoma)