Lecture 13 - Influenza

Question 1

Influenza vs common cold?

Answer 1

abrupt onset, 5+ day bedrest, chills, chest problems

Question 2

Cytokin linkage?

Answer 2

short incubation period, rapid onset, cytokin production e.g. IFN-alpha produces symptoms to promote healing

Question 3

Influenza interaction w epithelial cell?

Answer 3

Haemagglutinin protein on capsid of virus binds to sialic acid on the epithelial cell membrane

Question 4

Immune development?

Answer 4

haemagglutin-binding antibodies produced preventing binding to sialic acid - immunity to strain

Question 5

Loss of immunity?

Answer 5

genetic drift of the virus causes changes in the haemagglutin that eventually aren’t binded by antibodies

Question 6

Neuraminidase function?

Answer 6

snip interaction between sialic acid and haemagglutin

Question 7

Neuraminidase inhibitor function?

Answer 7

increase adhesion to initial cell preventing spread of virus- early effect only

Question 8

Vaccination production?

Answer 8

Haemagglutin gene of circulating virus attached to non-virulent lab strain

Question 9

Influenza types?

Answer 9

A: different types of HA and NA, epidemics and pandemics; B: single type of HA and NA, epidemics only; C: common cold, minor illness

Question 10

Antigenic shift?

Answer 10

Change in H protein, e.g.H5 has no human immunity therefore could cause pandemic if adapted to human cells due to easy transmission