influenza Flashcards
1
Q
signs and symptoms
A
- fever
- headache
- muscle aches/pains
- fatigue
- sore throat
- cough
2
Q
transmitted via
A
- contact with respiratory droplets
- airborne via respiraotry droplet nuclei
- contact with fomites contaminated with respiratory droplets
3
Q
shape
A
enveloped
(-) ss RNA genome
segmented genome
4
Q
pathogenesis
A
- the virus attaches to and infects epithelial cells in the URT
- replicates inside the cells, damaging the cells
- spreads to lower respiraotry tract and sometimes secondary bacterial infections occur
5
Q
virulence factor
A
spikes
* hemagglutinin
* neuraminidase
6
Q
hemagglutinin
A
- fililitates viral entry
- binds to sialic acid on host cells which act as receptors
- sialic acid is a small sugar that is attached to many different proteins on the cell surface
7
Q
neuraminidase
A
- facilitates virion release from the cell by cleaving sialic acid
- degrades mucin layer of respiraotry tract
8
Q
antigenic drift
A
MINOR changes caused by genetic mutation
* resulitng from RNA replication errors
* RNA polymerase has low fidelity
* graudal
* occurs with influenza A, B, C
9
Q
Antigenic shift
A
MAJOR changes caused by genetric reassortment
* adrupt
* occurs with influenza A only
10
Q
Influenza A
A
- severe
- animal reseervoir
- shift AND drift
11
Q
influenza B
A
- moderate
- epidemic
- drift
12
Q
influenza C
A
- mild
- sporadic
- drift
13
Q
Avian H5N1 (bird flu)
A
- highly virulent in humans
- cannot be transmitted human-to-human
14
Q
treatment
A
infleunza antivirals
15
Q
NA inhibitor drugs
A
inhibit neuraminidase from unbinding to host cell, stops viral replication
