Case 1 - Fresher's flu

Question 1

What is the unique symptom for common cold? (compared to flu)

Answer 1

• Runny nose/sneeze

- Sore throat (common)

Question 2

What are unique symptoms for flu? (compared to cold)

Answer 2

• Fever
• Headaches
• Feel sick/tired
• Dry cough (common)

Question 3

What are the common symptoms for cold and flu?

Answer 3

• Cough
• Aches & pain
• Fatigue

Question 4

What are the common symptoms for coronavirus?

Answer 4

• Fever
• Cough
• Loss of smell/taste
• Shortness of breath

Question 5

What is essential to evaluate various differential diagnoses?

Answer 5

Patient history

• Why they are here now, and not before
• Open ended qs
• Listen and observe (body language, nonverbal cues)

Question 6

Why is time such an important element to diagnosis?

Answer 6

• Reason for why patient is here (could have had symptoms since long time ago)
• How have symptoms changed since beginning
• Did symptoms sudden show up

Question 7

Onset of symptom; cold vs flu

Answer 7

Cold - gradual

Flu - rapid

Question 8

Meningitis symptoms

Answer 8

• Headache
• High fever
• Rash

Question 9

Why think about Meningitis, Glandular fever, infectious mononucleosis, Epstein Barr virus etc?

Answer 9

Rare differential diagnosis, must always see if can be excluded

Question 10

what can a sore throat (+ fever) be a symptom of?

Answer 10

Most often a viral infection, but could also signal diptheria or streptococcal infection (Strep throat - bacterial)

Question 11

What are the potential post-covid syndromes? (4 groups)

Answer 11

• Aches/pain
• Myalgia (muscle pain)
• Inflammatory response
• Severe lung fibrosis

Question 12

What are the viruses that cause the common cold?

Answer 12

• Rhinovirus (most common)
• Coronavirus
• Influenza virus (also flu)
• Adenovirus

Question 13

What glycoprotein does coronavirus attach to?

Answer 13

ACE2

Question 14

What glycoproteins do Influenza virus attach to?

Answer 14

Protein on virus:

• Haemagglutinin (HA)
• Neuraminidase (NA)

Receptor:
- Sialic acid

Question 15

What glycoprotein does rhinovirus attach to?

Answer 15

ICAM1

Question 16

What is the angiotensin system?

Answer 16

Physiological system

Question 17

What does angiotensin II cause?

Answer 17

Lung injury
Vasoconstriction
etc.

Question 18

How does coronavirus enter cell?

Answer 18

Uses ACE2 - Angiotensin Converting Enzyme type 2

Question 19

How does coronavirus control the angiotensin system?

Answer 19

Mitigate the counter protective system

A-(1-7)/(1-9) are anti-inflammatory, A-II is pro-inflammatory

Virus stops ACE2 converting A-II to A-I, therefore exacerbate lung injury

Question 20

How does influenza virus get into cell?

Answer 20

Viral HA bind to sialic acid residue on lung surface epithelial cell

Question 21

How does influenza virus get out of cell?

Answer 21

Viral NA cleaves sugar (galactose) that connects sialic acid to cell

Question 22

How to predict severity of airway damage?

Answer 22

ICAM1 further up (less severe)

Epithelial cells deeper into lung (more severe)

Question 23

What are the risk factors to increase risk for infectious disease?

Answer 23

Age
Co-morbidities
Immune/chronic disorders
Pregnant
Living in long term facilities
Obesity 
ETC.

Question 24

How do we know who to vaccinate?

Answer 24

Depending on risk factors

Question 25

How do stress, sleep and exercise increase risk of infection?

Answer 25

• Increase stress (high cortisol lv. immunosuppressant)
• Decrease sleep
• Too little/much exercise (hormone leptin produced by fat - low fat, low leptin, immune system switch off)

Question 26

What affects illness behaviour?

Answer 26

External influences (physical, psychosocial, financial, economical)

eg parent behaviour

Question 27

Why people would go and see doctor?

Answer 27

• Interpersonal crisis - life event (passed away family also have symptom)
• Interference w/ personal/social relations (Friends meeting)
• Sanctioning (Family/friend said so)
• Interference w/ vocation/physical activity (Work-earning money, sport)
• Temporalizing (Give a deadline to oneself)

Question 28

What types of vaccines are there?

Answer 28

• Viral vector
• DNA
• RNA
• Live-attenuated
• Protein-based

Question 29

What is a viral vector vaccine?

Answer 29

Different engineered virus carrying surface protein gene

Question 30

What is a DNA vaccine?

Answer 30

Plasmid synthesised that encodes gene for viral surface protein

Question 31

What is a RNA vaccine?

Answer 31

Messenger RNA encoded with surface protein gene

Question 32

What is a live-attenuated vaccine?

Answer 32

Weakened/recoded version of virus

Question 33

What is a protein-based vaccine?

Answer 33

Surface proteins synthesised & combined with adjuvant to enhance immune response

Question 34

What is an antigenic drift?

Answer 34

Small genetic changes with each replication (hence need yearly new vaccines)

Question 35

What is an antigenic shift?

Answer 35

Abrupt, major change in genetic material

• risk of pandemic
• only in Influenza A

Question 36

How does antigenic shift occur?

Answer 36

Different strains of virus infect same cell, genetic material combine to produce new virus with mixed genes (In influenza, new HA/NA combinations)

Question 37

How does new influenza types get produced with animals?

Answer 37

Pigs can be infected with HA molecules that humans do not get infected with, therefore act as reservoir of genetic reassortment of influenza A HA/NA genes to produce viruses capable of infecting humans from the avian influenza pool.