Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
82 Cards in this Set
- Front
- Back
|
Paramyxoviridae
naked or enveloped? |
enveloped
|
|
|
Paramyxoviridae
describe nucleocapsid |
enveloped, helical
|
|
|
Paramyxoviridae
shape? |
pleomorphic (156-300 nm in diameter)
|
|
|
Paramyxoviridae
What are the two viral glycoproteins in the envelop? |
a. Fusion protein -F protein (penetration)
b. Viral attachment protein (VAP) HN, H or G depending on virus |
|
|
What are the three genera of Paramyxoviridae family?
|
Morbillivirus
Paramyxovirus Pneumoviruses |
|
|
Name an example of Morbillivirus.
|
measles (rubeola)
|
|
|
Name three Paramyxioviruses/
|
Paramyxovirus, mumps virus, parainfluenza 1-4
|
|
|
Name two Pneumoviruses.
|
Respiratory syncytial virus (RSV), Metapneumovirus
|
|
|
Paramyxoviruses are respiratory viruses transmitted by ____.
|
aerosols (virus in respiratory droplet)
|
|
|
Paramyxoviruses
Where does initial replication occur? |
respiratory tract
|
|
|
Paramyxovirus infections cause cell to cell fusions resulting in ____ ____.
|
syncytia formation (aka, giant cells or polykarions)
|
|
|
Most paramyxoviruses can spread from cell to cell, evading ____ ____.
|
neutralizing antibody
|
|
|
Paramyxovirus VAP causes ____.
|
haemagglutination
(**not true for RSV) |
|
|
Paramyxovirus
Indirect pathology is caused by ____ ____ ____, which is also needed to clear the virus. |
cell mediated immunity
|
|
|
How many measles (rubeola) serotypes?
|
only one!
|
|
|
Infection with measles (rubeola) causes what?
|
red measles (rash disease)
|
|
|
How long does immunity to measles (rubeola) last?
|
lifelong
|
|
|
What creatures can host measles (rubeola)?
|
only humans
|
|
|
Measles Virus clinical symptoms.
|
CCC&P
Cough, Conjunctivitis, Coryza & Photophobia (**Coryza is acute rhinitis) |
|
|
After one week of infection, what are symptoms of Measles Virus?
|
Macuolopapular rash & high fever
|
|
|
What are Koplik's spots and what are they diagnostic for?
|
small white spots (1-2 mm) resembling salt grains, found on buccal mucosa & other membranes
usually appear 1-2 days before macuolopapular rash **Measles Virus! |
|
|
Is maculopapular rash (red measles) contagious?
|
NO!!
|
|
|
Describe maculopapular rash.
|
-mix of macules and papules
-extensive rash, beginning below ears, then spreading -takes 1-2 days to spread over body -fades 1-2 days after it appears |
|
|
Measles infections begin in the ____ ____, but this virus causes systemic disease.
|
respiratory tract
|
|
|
How is measles virus spread through the body?
|
viremia
|
|
|
What causes the characteristic measles rash?
|
T-cells reacting with virus infected cells in the capillaries of skin.
|
|
|
What are some complications of measles virus?
|
Pneumonia and bacterial complications are responsible for the majority of measles death (60%)
|
|
|
Encephalitis occurs in 0.5% of measles cases (15% fatal), and ocurs 7-10 days after infection.
What causes this complication? |
demyelination of neurons - primary damage caused by virus
|
|
|
If you are going to get measles, do you want atypical measles?
|
NO! --> way more intense.
|
|
|
What's the problem with atypical measles?
|
Immunopathology associated with a wild type measles infection of a patient vaccinated with inactivated virus vaccine --> insuficient protection induced by vaccine, but enhanced immunopathology.
|
|
|
What is SSPE?
|
Subacute sclerosing panencephalitis.
2-20 years after measles infection, infecting virus is defective. |
|
|
Measles Virus - Laboratory DIagnosis
|
Based on clinical presentation (rash, kopolik's spots, CCC&P)
MAB and other diagnostic reagents available. |
|
|
Measles prevention
|
live, attenuated measles vaccine
(included in MMR, provides lifelong immunity) |
|
|
Why shouldn't killed vaccine be used for measles vaccination?
|
predisposes recipients to atypical measles
|
|
|
Measles - Antivirals?
|
nope
|
|
|
Measles - Passive Immunity
|
effective and available to immunocompromised pts
|
|
|
Mumps - genus
|
paramyxovirus
|
|
|
Mumps - symptoms
|
acute, benign viral parotitis (and swelling of other glands)
|
|
|
Mumps - typically fatal?
|
nope
|
|
|
How many serotypes of mumps virus?
|
one
|
|
|
How is mumps virus spread to parotid and other glands?
|
viremia
stensens duct (for parotid) |
|
|
How is mumps virus acquired?
|
aerosol droplet, fomites
|
|
|
Mumps - initial replication
|
URT
|
|
|
Mumps causes damage via ____ pathology.
|
indirect
|
|
|
With mumps virus, what percent of pts have CNS infection?
|
50%
|
|
|
Pre-vaccination, what percent of the population would be infected with mumps virus?
|
90% -- highly infectious!!!
|
|
|
Mumps - How long do pts shed virus before symptoms?
|
7 days
|
|
|
Are all pts infected with mumps virus symptomatic?
|
nope - some are just carriers (lucky ducks)
|
|
|
Mumps - When is incidence higher?
|
winter & spring
|
|
|
Mumps virus - Laboratory Diagnosis
|
virus isolated from saliva, URINE, pharynx, CSF
serology used to detect antiviral antibody Hemagglutination |
|
|
Mumps Infection - serology findings
|
4x increase in anti-mumps IgG
appearance of anti-mumps IgM |
|
|
Mumps - Treatment
|
treat symptoms (discomfort) - not fatal, no antivirals, just your normal everyday drag.
|
|
|
Mumps - Vaccine
|
live attenuated virus
part of MMR vaccine |
|
|
Parainfluenza - genus
|
paramyxovirus
|
|
|
Parainfluenza - serotypes
|
four serotypes
1, 2 + 3 - important agents of lower respiratory tract infection in younger children (associated w/ croup) ***serious disease in children!! 4 - mild UTR symptoms |
|
|
Parainfluenza - spread
|
spread by aerosol route or direct contact
|
|
|
Parainfluenza - viremia?
|
nope - no systemic spread
|
|
|
Which cells does parainfluenza infect?
|
epithelial cells in URT
|
|
|
Parainfluenza - direct pathology
|
cause GIANT CELL formation
|
|
|
Parainfluenza - general symptoms
|
cold like symptoms
**croup is more serious (sub-glottal swelling, cough, tachypnea, tacycardia, suprasternal retraction) |
|
|
Parainfluenza - croup symptoms
|
cold like symptoms
**croup is serious in children! sub-glottal swelling, cough, tachypnea, tacycardia, suprasternal retraction |
|
|
How long does it take pts to recover from parainfluenza infection generally?
|
48 hrs
|
|
|
Is reinfection common with parainfluenza?
|
yes - severity of disease declines with reinfection
|
|
|
When is parainfluenza most common?
|
1+2 in fall, 3 year-round
|
|
|
Parainfluenza - Lab Diagnosis
|
readily isolated from nasal and respiratory secretion
identified by CPE, hemagglutination, Hexaplex PCR |
|
|
Hexaplex PCR assay
|
parainfluenza viruses 1, 2, 3, RSV types A and B, influenza types A and B
|
|
|
Parainfluenza - treatment
|
**infants w/ croup need careful monitoring!!
treat symptoms with nebulizers |
|
|
Parainfluenza - antivirals?
|
no
|
|
|
Parainfluenza - vaccine?
|
nope - no effective killed vaccine has been established that will stimulate local immunity. no attenuated vaccine either.
|
|
|
Respiratory Syncytial Virus (RVS) - genus
|
paramyxovirus
|
|
|
How does RSV differ from other paramyxoviridae?
|
lack of neuraminidase activity
|
|
|
Does RSV hemmagglutinate red blood cells?
|
nope
|
|
|
RSV - how does infection occur?
|
aerosol-borne virus (like all the other paramyxoviruses)
|
|
|
RVS infects the ____ respiratory tract.
|
lower
|
|
|
RSV - direct pathology??
|
YES - direct cytopathology caused by viral fusing of infected and uninfected cells (F protein)
|
|
|
RSV symptoms
|
from cold-like to pneumonia, pts may exhibit fever, tachypnea, tachycardia and wheezing
|
|
|
How infectious is RSV?
|
"blows through daycares"
very common, very contagious, widespread. |
|
|
When do RSV infections primarily occur?
|
winter
|
|
|
RSV - Laboratory Diagnosis
|
virus detected using kits that test for viral antigen - Hexaplex PCR
Nasal or respiratory aspirates tested by IF or ELISA (fast) Virus isolation (difficult) Serology (never used) |
|
|
RSV - antiviral?
|
Ribavarin - administered by nebulizer (usu in clinic or hospital setting)
|
|
|
Describe Ribovarin efficacy.
|
guanosine monophosphate analogue -- inhibits nucleoside biosynth, mRNA capping, RNA replication
|
|
|
RSV - passive immunization?
|
yes - available for immunocompromised pts or premature babies
|
