orthomyxoviridae and paramyxoviridae Flashcards Preview

LAST EXAMMMMMM Year I > orthomyxoviridae and paramyxoviridae > Flashcards

Flashcards in orthomyxoviridae and paramyxoviridae Deck (32):
1

The orthomyxoviruses generally cause what

the flu
with fever, muscle aches and HA

2

What bacterial pneumonias are common after viral orthomyxovirus infection

S aureus, H influenzae or St pneumoniae

3

what is the outside structure of orthomyxoviruse

has 2 types of glycoproteins
Hemagglutinin Activity HA
and Neuraminidase Activity NA which anchor to M proteins in lipid bilayer

4

HA hemagglutinin attach where

sialic acid R on host cells
so on RBCs and upper respiratory cells

5

What is the role of neuraminidase

it cleaves neuraminic acid which is important defensive component of mucin

6

What are the 3 types of influenza viruses? which ones are human only

A B C
BC are only human

7

What is antigenic drift

mutations in HA or NA
small changes

8

What is antigenic shift

complete change of HA or NA

9

when was the spanish flu and what type of virus was it

1918 H1N1

10

What is Reyes syndrome

children given aspirin while having flu or varicella
severe liver and brain disease

11

What are the 4 broad categories of Dx testing for influenza

viral isolation in culture
detection of viral proteins
detection of viral nucleic acid RNA- PCR
serological Dx 4X increase in titers over 2 week period

12

What are the clinical manifestations of H5N1

incubation 2-4 days have high fever, HA, mayalgias, diarrhea, abdominal pain, vomiting, sore throat and rinorrhea
cough, SOB and sputum production
** unique: clinical pneumonia with diffuse patchy infiltrates that consolidate with air bronchograms
Progresses to ARDS

13

How do you Dx H5N1

viral culture or reveres transcriptase PCR of viral RNA from pharyngeal or nasal washings
Ag-Ab detection of 4X increase in H5-specific Ab

14

What are the main differences of paramyxovirus vs ortho

negative stranded RNA is single strand- not segmented
HA and NA are same glycoprotein
have F protein

15

What does the fusion or F protein in paramyxoviruses do

fuse together to make multinucleated giant cells

16

What are teh 5 paramyxoviruses that cause human disease

parainfluenza, repiratory syncytial, metapneumonvirus, mumps and measles

17

Where do the paramyxoviruses manifest

lungs
upper respiratory tract - adults bad colds
lower respiratory tract- children pneumonia

18

what does parainfluenza virus cause

URI in adults
pneumonia in kids and elderly

19

What is croup

parainfluenza infection of larynx
causes wheezing and barking cough

20

How is Respiratory syncytial virus different from the rest of the family viruses

does not have HA or NA glycoprotein
has F protein

21

what is the leading cause of pneumonia in children under 6 months

RSV

22

what age group is generally infected by metpneumovirus

children in the year old range
can cause croup too

23

What is the general presentation of mumps

3 wks post exposure
parotiditis
orchitis

24

how does measles spread

nasopharyngeal secretions by air or direct contact

25

Describe the prodromal period of measles

conjunctivitis, swelling of eyelids, photophobia, high fevers, hackin cough, rhinitis and malaise

26

What are koplik spots

red lesions with blue and white centers in the mouth- usually 1-2 days before measles rash

27

describe rash caused by measles

red flat-slightly bumpy
starts forehead and spreads down
disappears in same manner- 6 days

28

What is the most serious complication of measles infection

encephalitis

29

infection of measles during pregnancy can cause what

spontaneous abotion, premature delivery

30

What is the slow form of encephalitis caused by measles

subacture sclerosing panencephalitis
mental deterioration and incoordination

31

where does orthomyxovirus replicate? paramyxo?

ortho in nucleus
para in cytoplasm

32

which paramyxovirus does not have F protein

metapneumovirus