RNA Viruses - Positive Sense - Picornaviridae Flashcards
Which Sketchy image represents an overview of the Picornaviridae family?
Which Sketchy image represents Poliovirius?
Of what family is this virus a member?
Picornaviridae
Which Sketchy image represents Coxsackievirus (A and B)?
Of what family is this virus a member?
Picornaviridae
Which Sketchy image represents Rhinovirus?
Of what family is this virus a member?
Picornaviridae
Which Sketchy image represents the Hepatitis A virus?
Of what family is this virus a member?
Picornaviridae
Identify as many of the marked points in this image as you can.
Note: this is an overview of the Picornaviridae family.
Identify as many of the marked points in this image as you can.
Note: this is Poliovirus.
Identify as many of the marked points in this image as you can.
Note: this is Coxsackievirus (A and B).
Identify as many of the marked points in this image as you can.
Note: this is Rhinovirus.
Identify as many of the marked points in this image as you can.
Note: this is the Hepatitis A virus.
Name the main viruses of the Picornaviridae family.
Hepatitis A virus,
enteroviruses (e.g. poliovirus, coxsackievirus A and B, echovirus),
and Rhinovirus
Hepatitis A virus is a(n) _______ virus that is a member of the _______viridae family.
Hepatitis A virus is an RNA virus that is a member of the _Picorna_viridae family.
Poliovirus is a(n) _______ enterovirus that is a member of the _______viridae family.
Hepatitis A virus is an RNA enterovirus that is a member of the _Picorna_viridae family.
The Coxsackie A and B viruses are _______ enteroviruses that are members of the _______viridae family.
The Coxsackie A and B viruses are RNA enteroviruses that are members of the _Picorna_viridae family.
Echovirus is a(n) _______ enterovirus that is a member of the _______viridae family.
Echovirus is an RNA enterovirus that is a member of the _Picorna_viridae family.
Rhinovirus is a(n) _______ virus that is a member of the _______viridae family.
Rhinovirus is an RNA virus that is a member of the _Picorna_viridae family.
Picornaviruses (e.g. hepatitis A virus, poliovirus, coxsackievirus A and B, echovirus, Rhinovirus) are _______ (RNA/DNA), _______ (naked/enveloped) viruses.
Picornaviruses (e.g. hepatitis A virus, poliovirus, coxsackievirus A and B, echovirus, Rhinovirus) are RNA, naked viruses.
Picornaviruses (e.g. hepatitis A virus, poliovirus, coxsackievirus A and B, echovirus, Rhinovirus) are _______-sense RNA viruses.
Picornaviruses (e.g. hepatitis A virus, poliovirus, coxsackievirus A and B, echovirus, Rhinovirus) are positive-sense RNA viruses.
How are most members of the Picornaviridae family transmitted?
The fecal-oral route
Which member of the Picornaviridae family is not transmitted via the fecal-oral route?
Rhinovirus
(transmitted via respiratory droplets)
What viral proteins do picornaviruses (e.g. hepatitis A virus, poliovirus, coxsackievirus A and B, echovirus, Rhinovirus) need to carry into host cells?
Viral proteases only
(host ribosomes used for translation)
The whole genome of picornaviruses (e.g. hepatitis A virus, poliovirus, coxsackievirus A and B, echovirus, rhinovirus) is translated into one long __________ that is cleaved by host and viral ___________.
The whole genome of picornaviruses (e.g. hepatitis A virus, poliovirus, coxsackievirus A and B, echovirus, rhinovirus) is translated into one long polyprotein that is cleaved by host and viral proteases.
Hepatitis A virus can cause ______itis, ______itis, and __________megaly.
Hepatitis A virus can cause hepatitis, gastroenteritis, and hepatosplenomegaly.
_____________ are the number one cause of aseptic meningitis.
Enteroviruses are the number one cause of aseptic meningitis.
Describe the CSF findings in a patient with aseptic meningitis:
CSF glucose — _______
CSF organisms — _______
CSF protein — _______
Describe the CSF findings in a patient with aseptic meningitis:
CSF glucose — normal (‘no sugar added’)
CSF organisms — none (‘no organisms’)
CSF protein — elevated (‘source of protein’)
_________ _________ (caused by viruses such as enteroviruses [e.g. poliovirus, coxsackievirus A and B, and echovirus]) is a self-limited inflammation of the meninges in which a virus, not bacteria, is the causative agent.
Aseptic meningitis (caused by viruses such as enteroviruses [e.g. poliovirus, coxsackievirus A and B, and echovirus]) is a self-limited inflammation of the meninges in which a virus, not bacteria, is the causative agent.
Viral meningitis caused by enteroviruses (e.g. poliovirus, coxsackievirus A and B, and echovirus) most commonly what age group?
Children
A patient presents with meningitis. CSF analysis shows normal glucose levels, elevated protein, and no organisms.
Assuming a viral cause, what is this presentation called?
Aseptic meningitis
Rhinovirus infection affects the _______ _______ tract and is spread via respiratory droplets.
Rhinovirus infection affects the upper respiratory tract and is spread via respiratory droplets.
Poliovirus is a _________-sense ______ virus in the Picornaviridae family.
Poliovirus is a positive-sense RNA virus in the Picornaviridae family.
Is poliovirus naked or enveloped?
Naked
Poliovirus is acid-________.
Poliovirus is acid-stable (allowing it to enter the gut and replicate in the Peyer’s patches).
Where does replication of poliovirus occur?
The gut mucosa (e.g. Peyer’s patches)
What is the main cell type affected by poliovirus?
Motor neurons of the spinal cord anterior horn
The paralysis seen in poliovirus infection is typically __________.
The paralysis seen in poliovirus infection is typically asymmetric.
The muscle weakness caused by poliovirus is associated with ___________ failure.
The muscle weakness caused by poliovirus is associated with respiratory failure.
Poliovirus is a potential cause of _________ meningitis.
Poliovirus is a potential cause of aseptic meningitis.
The Salk vaccine is an inactivated (killed) vaccine administered by injection to prevent polio. What antibodies are produced in response?
IgG
The Sabin vaccine is a live-attenuated vaccine administered PO to prevent polio. What antibodies are produced in response?
IgG
+
IgA
IgG production is stimulated by which poliovirus vaccine(s)?
Salk and Sabin
IgA production is stimulated by which poliovirus vaccine(s)?
Sabin only
(administered PO)
Coxsackieviruses A and B are both ________-sense _____ viruses in the Picornaviridae family.
Coxsackieviruses A and B are both positive-sense RNA viruses in the Picornaviridae family.
Are coxsackieviruses naked or enveloped?
Naked
What is the main clinical presentation of coxsackie A virus?
‘Hand, foot, and mouth disease’
(a red, vesicular rash in the mouth, on the fingers and palms of the hands, and the soles of the feet)
A patient presents with a red, vesicular rash in the mouth, on the fingers and palms of the hands, and the soles of the feet. VDRL and RPR tests both come back negative.
What etiology do you suspect?
Coxsackievirus A
Which coxsackievirus can cause aseptic meningitis?
Coxsackie A virus
Coxsackieviruses commonly affect ____________ during ________ months.
Coxsackieviruses commonly affect young children during summer months.
What is the main sequalae of coxsackievirus B infection?
Myopericarditis leading to dilated cardiomyopathy
Coxsackievirus B causes ___________ disease (also known as the devil’s grip or epidemic __________), which is characterized by severe, unilateral pleuritic pain in the lower chest.
Coxsackievirus B causes Bornholm disease (also known as the devil’s grip or epidemic pleurodynia), which is characterized by severe, unilateral pleuritic pain in the lower chest.
A patient presents with severe, unilateral pleuritic pain in the lower chest.
What viral infection may be involved?
Coxsackievirus B
(Note: this presentation is Bornholm’s disease / the “devil’s grip” / epidemic pleurodynia.)
Via what two mechanisms can rhinovirus be transmitted?
Respiratory droplets;
fomites
Why isn’t rhinovirus transmitted via the fecal-oral route?
It is acid-labile
Rhinovirus can only enter host cells after binding what on the host cell surface?
ICAM-1
Rhinovirus grows best at ___°C.
Rhinovirus grows best at 33°C (e.g. in the air-cooled respiratory tract).
True/False.
Rhinovirus only infects cells of the upper respiratory tract.
True.
Why is there no vaccine for rhinovirus (i.e. why haven’t we eliminated the main cause of the common cold)?
There are 100+ rhinovirus serotypes
Hepatitis A virus is a __________-sense ______ virus in the Picornaviridae family.
Hepatitis A virus is a positive-sense RNA virus in the Picornaviridae family.
What are the three main sequalae of infection with hepatitis A virus?
(2 ‘-itis’ and 1 ‘-megaly’)
Hepatitis, gastroenteritis, and hepatosplenomegaly
Hepatitis A virus is acid-________.
Hepatitis A virus is acid-stable.
Is hepatitis A virus naked or enveloped?
Naked
How is hepatitis A virus transmitted?
The fecal-oral route
Name four ways by which water contaminated with hepatitis A virus can be purified.
- Chlorination
- Bleach
- UV irradiation
- Boiling
Contaminated __________ and/or __________ are common sources of hepatitis A virus in high-income countries.
Contaminated water and/or shellfish are common sources of hepatitis A virus in high-income countries.
Hepatitis A virus infection is commonly seen in travelers in areas where HAV is ___________.
Hepatitis A virus infection is commonly seen in travelers in areas where HAV is endemic.
How does hepatitis A virus infection typically present (in either children or adults)?
Nausea/vomiting
+
abdominal pain
How does hepatitis A virus infection present differently in children/infants and adults?
Children/infants — more likely to be anicteric;
adults — more likely to be icteric
Smokers with hepatitis _____ often develop an aversion to smoking.
Smokers with hepatitis A often develop an aversion to smoking.
The duration of hepatitis A symptoms typically last how long?
1 month
(self-limiting)
How often do individuals develop chronic hepatitis A infection or become carriers for the virus?
Never!
(It is just about always a self-limiting course of one month of S/Sy.)
The hepatitis A vaccine is a(n) ____________ vaccine.
The hepatitis A vaccine is a killed vaccine.
A patient presents with nausea, vomiting, and abdominal discomfort. He notes that he recently visited an oyster bar. He notes a darkening of his urine, and physical examination reveals a slight yellowing of his skin and sclerae. Lab results indicate markedly elevated ALT and AST with ALT > AST.
What is the likely diagnosis?
Hepatitis A infection
