Influenza

Question 1

Who is at risk for serious complications?

Answer 1

-65 yrs and older
-Nursing home residents
-persons with chronic diseases
-pregnant women
-infants

Question 2

What kind of diseases are Influenza?

Answer 2

Respiratory Viruses

Question 3

How is Influenza transmitted

Answer 3

Through contact with respiratory droplets from coughing and sneezing

Question 4

What is an Incubation period?

Answer 4

How long before you look and feel ill

Question 5

What is the incubation period of Influenza?

Answer 5

1-5 days from exposure to symptoms

Question 6

What is Communicabiltiy?

Answer 6

How long before you are contagious

Question 7

What is the communicability period of Influenza?

Answer 7

1-2 days prior to symptoms and 4-5 days after symptoms

Question 8

What is peak time for the flu in North America?

Answer 8

December through March

Question 9

What are the symptoms of Influenza?

Answer 9

A rapid onset of….
-fever and chills
-body aches, headaches, sore throat
-non-productive cough ; runny nose

Question 10

True or false:
Diarrhea and Vomiting are common with Influenza

Answer 10

False- they are rare symptoms

Question 11

True or False:
Virus in the bloodstream is common

Answer 11

False

Question 12

What does it mean if Influenza is Group A

Answer 12

-can do both antigenic shift & drift
-epidemics/pandemics, risk to all ages
-infects humans AND animals

Question 13

What does it mean if Influenza is Group B

Answer 13

-can only do antigenic drift
-risk to children and aged
-slow, mutational change through the year
-ONLY infects humans

Question 14

What is Group B Influenza also known as?

Answer 14

The seasonal flu

Question 15

What does it mean if Influenza is Group C

Answer 15

-mild respiratory tract infections
-no epidemics

Question 16

What structures are found in the Influenza virus?

Answer 16

-segmented ssRNA genome
-helical capsid
-Envelope with H-spikes & N-spikes
-matrix proteins
-Virus RNA polymerase

Question 17

What do helical capsids do in the virus structure?

Answer 17

protect nucleic acid genome

Question 18

What do h-spikes do in the virus structure?

Answer 18

used to get into host cells

Question 19

What do n-spikes do in the virus structure?

Answer 19

used to get out of host cells

Question 20

What do matrix proteins do in the virus structure?

Answer 20

allows virus to associate its capsid with the envelope

Question 21

What do Virus RNA polymerase do in the virus structure?

Answer 21

replicates negative viral strand

Question 22

What are Group-Specific Antigens?

Answer 22

-capsid distinguishes Groups A,B,C
-Antibody vs capsid does NOT neutralize virus

Question 23

What are Type-Specific Antigens?

Answer 23

-H and N proteins
-Antibody vs H neutralizes virus

Question 24

What are factors of antigenic drift?

Answer 24

-occurs in H and N
-MINOR change in antigens
-Associated with Group B
-mutations

Question 25

What are factors of antigenic shift?

Answer 25

-occurs in H and N
-MAJOR changes in antigens
-Associated with Group A
-Flu’s segmented genome can re-assort
-Re-assort new H’s or new combos of H and N
-animal flu viruses provide new segments

Question 26

What is the danger if antigenic shift occurs?

Answer 26

A pandemic may occur if…
-efficient & sustained human-human transmission
-widespread mobility & mortality worldwide
-high proportion of deaths among young adults

Question 27

What are the usual avian influenza A viruses?

Answer 27

H1 - H16
N1 - N9

Question 28

What are the usual human influenza A viruses?

Answer 28

H1 - H3

Question 29

True or False:
Different Flu Substrates can re-assort in a shared host

Answer 29

True

Question 30

What makes H5N1 so virulent?

Answer 30

it elicits an exaggerated cytokine response “storm” that can cause the body to kill itself, rather than the virus being the cause of death