Influenza Flashcards
influenza virus
contagious respiratory illness that infects animals, birds, and humans
HA
clumping/clustering of RBC
allows virus to bind to cells
NA
viral replication
allows the virus to be released from cell
influenza A
most virulent strain
found in humans, horses, swine, seals, whales, and birds
influenza B
strain found in humans
symptoms less severe than influenza A
influenza C
strain found in humans
common cold
influenza D
reservoir traces back to cattle
what are the most prevalent human flu viruses?
H1N1
H3N2
antigenic drift
MINOR genetic point mutations to HA/NA surface antigens
produce new virus strains
antigenic shift
MAJOR changes when two or more strains combine
people have no protection against new virus
results in a PANDEMIC
mode of transmission
seasonal influenze (A & B) spread by airborne transmission
again influenza spread by direct/close contact with infected birds
incubation period
1-4 days
humans can infect 1 day before symptoms appear/ 5 days after becoming sick
can be infected but have no symptoms/still spread the virus
complications of flu
bacterial pneumonia
ear infections
sinus infection
dehydration
worsening of chronic medical conditions
diagnosis
lab confirmation through isolation of virus from pharyngeal/nasal secretions
treatment
no cure
goal: prevent disease by pre-exposure vaccinations or decrease the severity of symptoms
