Influenza

Question 1

Influenza, commonly known as the flu, is a highly contagious respiratory illness caused by influenza viruses. How many adults worldwide does this affect?

1 - 1.5-2%
2 - 5-10%
3 - 20-30%
4 - >50%

Answer 1

2 - 5-10%

Question 2

Influenza, commonly known as the flu, is a highly contagious respiratory illness caused by influenza viruses. How many children worldwide does this affect?

1 - 1.5-2%
2 - 5-10%
3 - 20-30%
4 - >50%

Answer 2

3 - 20-30%

Question 3

Influenza, commonly known as the flu, is a highly contagious respiratory illness caused by influenza viruses. In most cases the effect of the virus is self limiting, but it can also cause complications in all of the following EXCEPT which one?

1 - children
2 - elderly
3 - pregnant women
4 - chronic diseases

Answer 3

1 - children

Question 4

Influenza, commonly known as the flu, is a highly contagious respiratory illness caused by influenza viruses. How is this typically transmitted?

1 - aerosol droplets
2 - direct contact
3 - sharing of bodily fluids
4 - sexual contact

Answer 4

1 - aerosol droplets

Question 5

Influenza, commonly known as the flu, is a highly contagious respiratory illness caused by influenza viruses. How many people die from the influenza virus each year?

1 - 500
2 - 5000
3 - 50,000
4 - 500,000

Answer 5

4 - 500,000
- typically occurs due to pneumonia or respiratory failure

Question 6

Once infected with influenza virus, how soon are you infective to others prior to symptoms?

1 - 1 day
2 - 3 days
3 - 7 days
4 - 2 weeks

Answer 6

1 - 1 day

Question 7

Once infected with influenza virus, how long are you infective to others once you are symptom free?

1 - 1 day
2 - 3 days
3 - 7 days
4 - 2 weeks

Answer 7

3 - 7 days

Question 8

Once infected with influenza, how soon is it before you typically present with symptoms?

1 - immediately
2 - 24h
3 - 48h
4 - 1-4 days

Answer 8

4 - 1-4 days
- symptoms typically last for 1-2 weeks

Question 9

Some patients have increased risks associated with influenza. All of the following patients are at a greater risk from this virus, EXCEPT which one?

1 - adults aged >65
2 - children aged <6 months
3 - chronic comorbidities
4 - immunocompromised

Answer 9

2 - <6 months

Question 10

Which of the following are common symptoms of the influenza virus?

1 - fever with body aches
2 - cough with sore throat
3 - runny or stuffy nose
4 - headache
5 - chills
6 - fatigue
7 - all of the above

Answer 10

7 - all of the above

Question 11

There are a myriad of different influenza viruses, but typically how many can affect humans?

1 - >6
2 - >4
3 - 3
4 - 1

Answer 11

3 - 3
- influenza A, B and C

Question 12

Influenza viruses A, B and C can infect humans, but which is most common?

Answer 12

• A
• also causes the most severe symptoms

Question 13

Which 2 of the following proteins can be found on the protective envelope surface of influenza A and B?

1 - haemagluttin (H)
2 - neuraminadase (N)
3 - spike protein (S)
4 - membrane protein (M)

Answer 13

1 - haemagluttin (H)
2 - neuraminadase (N)
- there are lots of variations of H and N though
- H3N2 is most common to infect humans

Question 14

Haemagluttin (H) and neuraminadase (N) are 2 key proteins found on the protective envelope surface of influenza A and B. There are lots of variations of H and N, but does influenza A or B have the most?

Answer 14

• influenza A

Question 15

Which of the following proteins can be found on the protective envelope surface of influenza C?

1 - haemagluttin (H)
2 - neuraminadase (N)
3 - spike protein (S)
4 - haemagluttin esterase Fusion

Answer 15

4 - haemagluttin esterase Fusion
- used to enter cells

Question 16

Of the 3 types of influenza, which one is most common in children?

1 - A
2 - B
3 - C
4 - all affect children equally

Answer 16

3 - C
causes mild illness in children

Question 17

Why is influenza A able to infect people consistently?

1 - previously produced B cells die off and do not synthesis antibodies for specific H and N antigens
2 - daughter cells mutate and change H and N proteins randomly during replication
3 - strains are always different from different countries
4 - all of the above

Answer 17

able to evolve over time for survival
- able to do this in or outside of host cells
- called genetic drift - IMPORTANT
- called drift as its a slow process

Question 18

In addition to genetic drift where influenza proteins slowly adapt for survival over time, antigenic shift can also occur in the influenza virus. What happens here?

1 - daughter cells rapidly adapt for survival
2 - influenza combined with other viruses to infect host cells
3 - 2 different cells infect the same cell and mix, causing new H and/or N proteins
4 - all of the above

Answer 18

3 - 2 different cells infect the same cell and mix, causing new H and/or N proteins
- linked with pandemics including the Spanish flu

• influenze virus has a segmental genome
• segmental genomes can therefore mix, similiar to miosis
• creates mixed and unique genome with new H and N proteins that are more likely to infect the host

Question 19

Typically when influenza A and B enter the body, they use haemagluttin (H) to bind to what on the epithelial cells of the upper respiratory tract?

1 - CD4 receptor
2 - MHC-1 receptors
3 - sialic acid sugar
4 - any of the above

Answer 19

3 - sialic acid sugar
- cell then engulfs the virus in endocytosis

Question 20

Once influenza virus is endocytosed by the epithelial cell it binds with what must then happen to it?

1 - negative single stranded (ss) RNA must be converted into positive ssRNA
2 - virus must enter nucleus and replace host DNA
3 - negative single stranded (ss) RNA must be chopped into small parts to be copied
4 - all of the above

Answer 20

1 - negative single stranded (ss) RNA must be converted into positive ssRNA
- RNA polymerase converts - into + ssRNA

• positive ssRNA is the same as mRNA which is what is needed before it can be copied by the ribosome to make proteins

Question 21

One the influenza virus has copied sufficient proteins in the host cell ribosome, new viruses are made and the protein is able to leave the cell. How does this happen?

1 - binds to MHC-I molecule to leave the cell
2 - neuraminadase cleaves sialic acid sugar and buds out of the cell
3 - haemagluttin cleaves sialic acid sugar and buds out of the cell
4 - neuramindase binds MHC-II and is able to leave the cell

Answer 21

2 - neuraminadase cleaves sialic acid sugar and buds out of the cell

Question 22

Which of the following is NOT a common complication of influenza virus?

1 - exacerbation of chronic lung disease
2 - pneumonia
3 - pneumothorax
4 - otitis media
5 - croup
6 - bronchiolitis and sinusitis

Answer 22

3 - pneumothorax

• croup = a common childhood infection causing a barking cough and a rasping sound when breathing. It’s usually mild but may need treatment

Question 23

Children <6 months may develop which of the following as a complication of influenza?

1 - CHF
2 - encephalitis
3 - meningitis
4 - febrile seizures

Answer 23

2 - encephalitis
4 - febrile seizures

Question 24

Reyes syndrome is a common complication that occurs in children after they have taken what?

1 - penicillin
2 - vancomycin
3 - aspirin
4 - prednisolone

Answer 24

3 - aspirin
- children may have this when they are infected with influenza

Question 25

Reyes syndrome is a common complication that occurs in children after they have taken what aspirin to relieve symptoms caused by influenza. Which 2 the following are part of reyes syndrome?

1 - encephalopathy
2 - liver disease
3 - CHF
4 - CKD

Answer 25

1 - encephalopathy
2 - liver disease

• this is very dangerous

Question 26

Diagnosing influenza virus is typically a clinical diagnosis. However, which 2 of the following are the most accurate methods for diagnosing a patient?

1 - viral PCR
2 - nasal or bronchial lavage
3 - blood culture
4 - viral culture of swabs from the body

Answer 26

1 - viral PCR
4 - viral culture of swabs from the body

Question 27

if a patient presents with a suspected influenza virus, how are they treated?

1 - antibiotics
2 - oseltamivir
3 - M2 channel inhibitors
4 - supportive care (analgesia, plenty of fluids)

Answer 27

4 - supportive care (analgesia, plenty of fluids)

Oseltamivir can be used if patient is hospitalised and is a high risk patient

Question 28

Patients with influenza are not typically treated with medications other than paracetamol as the flu is typically self limiting. However, in high risk patients, which 2 of the following may be used?

1 - neuraminidase inhibitors
2 - haemagluttin inhibitors
3 - M2 channel inhibitors
4 - spike protein inhibitors

Answer 28

1 - neuraminidase inhibitors
3 - M2 channel inhibitors
- used inside the host cell to help replicate

Question 29

Oseltamivir and zanamivir are 2 medications that that can be given to patients who are at high risk of complications due to the influenza virus. What is the mechanism of action of this drug?

1 - neuraminidase inhibitor
2 - haemagluttin inhibitors
3 - M2 channel inhibitors
4 - spike protein inhibitors

Answer 29

1 - neuraminidase inhibitor
- cell cannot leave the cell and so dies

Question 30

What is the most effective treatment for influenza virus?

1 - neuraminidase inhibitors
2 - haemagluttin inhibitors
3 - M2 channel inhibitors
4 - vaccinations

Answer 30

4 - vaccinations
- modelled on influenza proteins that are likely to dominate each season

Question 31

Children <6 months are most susceptible to influenza virus. Therefore caregivers should be vaccinated to protect the child. At what age can children get the influenza vaccine?

1 - >6 months
2 - >1 year
3 - >2 years
4 - >16 years

Answer 31

3 - >2 years
- typically offered every autumn, but not like the typical vaccination programme