URTI Flashcards
Describe rhinovirus
Icosahedral, non-enveloped positive sense single-stranded linear RNA virus
What family does Rhinovirus belong to?
Picornavirus
Rhinovirus is the most common cause of what?
common cold (more common in fall and winter)
T or F. Rhinovirus is acid labile
T. Destroyed by stomach acid
How is rhinovirus transmitted?
person-to-person via respiratory droplets or indirectly by respiratory droplets on hands
Pathogenesis of rhinovirus
virus binds to ICAM-1 on respiratory epithelial cells and elicits inflammation to cause vasodilation, mucous secretion, and stimulation of sneeze and cough reflexes
What is the incubation period of rhinovirus?
2-4 days (illness lasts about 1 week)
Treatment of rhinovirus?
Supportive only
Describe coronavirus
Helical, enveloped, + sense single-stranded linear RNA that accounts for 15-20% of URTIs
active in winter in a 2-3 yr cycle
T or F. Coronavirus does NOT cause LRTIs
T. except SARS and MERS
What else can coronavirus cause?
GI illness
Describe Bordetella pertussis
small coccobacillary, encapsulated gram negative rod
What disease does Bordetella pertussis cause?
Whooping Cough
What major toxin does Bordetella pertussis use?
A-B toxin
What does A-B toxin do?
stimulates adenylate cyclase by catalyzing the addition of ADP-ribosylation to the inhibitory subunit of the G protein complex, resulting in overactive cAMP- dependent protein kinase activity which impairs phagocytosis
How is Bordetella pertussis transmitted?
airborne droplets (very contagious)
What are the stages of Bordetella pertussis infection?
- catarrhal (2 wks of mild URT symptoms)
- paroxysmal (2-3 months of severe cough)
- Convalescent (1-2 wks of cough reducing)