19. Orthomyxoviruses 1 Flashcards
3 ways influenza can spread
- droplets (short distance)
- aerosols (microscopic particles in air)
- fomites on surface
most common cause of URI?
RNA viruses
what happens to vaccine efficacy when there are more serotypes in vaccine?
more serotypes in vaccine = reduced immune response
why do we have more colds in winter than summer?
kids go to school in the winter:
- kids are most common vector
- always see an increase in winter, regardless of location
is influenza the same as the common cold?
no
what happens 3 days after infection?
symptoms begin and there is max. virus shedding
what makes influenza different than other URI viruses?
other URI viruses cause endemic disease but influenza causes EPIDEMIC (in winter) and PANDEMIC disease
what type of people typically die from influenza?
old and immunocompromise
2 effects of the flu?
- infects and kills respiratory cells
- wipes out mucociliary defense
3 facts about respiratory mucociliary clearance
- uses mucus-secreting goblet cells
- uses ciliated epithelial cells
- causes a cough
describe basal cells in mucociliary system
pluripotent –> can become goblet or ciliary cells
what happens to mucociliary cells when there is infection?
increase in undifferentiated/basal cells, then eventually returns to normal cells
what type of genome does influenza have?
ssRNA segmented in 8 parts
describe the 6 proteins that make up the influenza particle
1) HA and 2) NA on the outside
3) M1 structural protein
4) 3 proteins make up polymerase
5) NP protein associated with RNA
6) NS1 nonstructural protein
describe the nucleocapsid
helical nucleocapsid of RNA + NP protein
