Enteroviruses Flashcards
Viral meningitis is most common in
Summer
What is the most common viral syndrome
Aseptic Meningitis
What are the symptoms of aseptic meningitis
Headache
Neck stiffness
Photophobia
Vomiting
Encephalitis is a disease of the grey or white matter?
Grey matter
What are symptoms of encephalitis ( different to aseptic meningitis) ?
Focal neurological signs
fever
drowsiness
confusion
convulsions
Causes of encephalitis
HSV1
Enteroviruses
Rabies
Arboviruses
Polioviruses target x and cause Y
Directly infect motor neurone in the spinal cord (anterior horn -> LMN weakness) and cause -> Acute flaccid paralysis
CSF results in Viral meningitis
- normal glucose
- normal protein levels
- elevated WCC milder than bacterial
List the 4 groups of Enteroviruses
puppies can excite nerves
- Polioviruses
- Coxsackie Viruses
- Echovirus
- Numbered enteroviruses
Polio and echoviruses are both
…..
family …
description
Enteroviruses
Family picornaviridae
Small, enveloped, ssRNA viruses
- spherical, symmetrical with external capsized composed of 4 viral proteins
What environment are enteroviruses suited to and why?
GIT - they are adapted to replicate in an acidic environment
When do enteroviruses peak?
Summer/ Autumn
When does coxsackie peak?
Summer/ Autumn
When does echovirus peak?
Summer/ Autumn
How are enteroviruses transmitted?
Faecal oral route
Who is most commonly effected by enteroviruses?
Children
What lab tests should be done for diagnosing an enterovirus?
Blood sample - if negative, does not rule out infection
Check stool
Check CSF if meningitis suspected
Which polio vaccine is now used and why?
IPV instead of Oral polio vaccine aka Sabin vaccine
because the Sabin vaccine was a live attenuated vaccine that caused an immune reaction.
Sabin vaccine produces IgA in the gut
When is a blood sample useful for diagnosis?
In neonates
90days
Where does replication of rhinovirus occur?
Epithelial cells in the resp tract at pH of 7
Bacteria, viruses, fungi or parasites are most common cause of meningitis
Viruses
Viral causes of acute flaccid paralysis
Polio 1,2,3
Enteroviruses
How do most enteroviruses manifest in the host
Asymptomatic
Difference between Enteroviruses and rhinoviruses?
EV are acid stable pH2
How long are enteroviruses shed for in the host?
1-3 weeks in URT
up to 8 weeks in faeces
What proportion of enteroviruses reach the RES and then cause major viraemia?
4-8% get to RES
1-2% cause major viraemia
Where do polioviruses replicate?
In gut associated lymphoid tissues
Polio targets the anterior horn of grey matter in spinal cord, T or F?
True
What proportion of polio infection results in paralysis?
Less than 1%
Which polio vaccine is associated with causing polio?
Oral polio virus ( live attenuated )
What is the immune response to the inactivated polio vaccine?
IgG in blood
What vaccine is available for enteroviruses?
No vaccine
Use of Pleconaril?
Used against rhinoviruses and enteroviruses in vitro
What type of antivirals are tried for enteroviruses?
Capsid inhibitors
- pocapavir
- pleconaril
Which usually has a better outcome, viral or bacterial meningitis?
Viral -
