Misc

Question 1

What is pyrexia of unknown origin?

Answer 1

• prolonged illness (2-3 weeks duration)
• fever (above 38.3ºC) on several occasions
• no diagnosis after intelligent investigations

Question 2

How is a fever defined?

Answer 2

Early morning oral temperature of >37.2 or oral temperature >37.8 at any time of the day
** remember that oral temp

Question 3

What is a rigor?

Answer 3

Feeling of intense cold, uncontrollable shivering, striking pallor of face and limbs, pilo-erection
- functions to heat the person up, so management is to heat them up to stop the rigor

Question 4

What is passive immunisation?

Answer 4

Treatment with antibodies or immune cells

- used for treatment/prevention

Question 5

What are pooled (standard) and hyperimmune types of passive immunisations?

Answer 5

The antibodies come from the blood/serum of donors

• these donors will have antibodies to a whole range of things –> pooled
• hyperimmune is from a donor who has had the disease very recently

Question 6

Who should you never give a vaccine to/think very hard about giving one to?

Answer 6

Immunocompromised and pregnant

Question 7

What are the different types of living immunising agents?

Answer 7

• unattenuated
• empirically attenuated
• rationally attenuated
• reassortants
• antigen expressed on living vector

Question 8

What is an empirically attenuated immunising agent?

Answer 8

• most common type
• the organism is grown under conditions it does not like, wait until it grows very well in these conditions and then the ideas is that it will grow less well in the host
• use for polio, measles, mumps, rubella, varicella zoster etc
• BCG for TB

Question 9

What is a rationally attenuated immunising agent?

Answer 9

• the toxic gene has been deleted form the genome but all the other components are still there
• so if the person makes an immune response it should make it to everything
• eg cholera, delete the cholera toxin gene

Question 10

What is a reassortment immunising agent?

Answer 10

• only used for viruses 2 that we use
• genes are encoded on different strands of RNA so can take one kind of the virus and put selected bits of double stranded RNA from a human virus
• -> express on its surface human virus antigens but won’t cause a human response
• use for influenza and rotavirus

Question 11

What are non-replicating immunising agents?

Answer 11

• inactivated virion/bacterium
• purified product, component (+/- modification)
• product of cloned gene
• synthetic immunogen
• DNA vaccine

Question 12

What are some advantages of living vaccines?

Answer 12

• broader, longer-lived immune response
• local immunity
• ease of administration

Question 13

What are some disadvantages of living vaccines?

Answer 13

• disease - back mutation, spread, contamination

- failure - dead, pre-existing immunity, interference

Question 14

What are some advantages of killed vaccines?

Answer 14

• stable, contamination unlikely, can’t spread, stable for immune deficit

Question 15

What are some disadvantages of killed vaccines?

Answer 15

• weaker immune response
• high dose
• need adjuvants
• expensive