Vaccine

Question 1

Types of vaccines

Answer 1

• Live vaccines
• Killed vaccines
• Sub unit vaccines
• Naked DNA vaccines

Question 2

Live attenuated vaccine

Answer 2

• They expose the individual to a weakened strain of a pathogen to activate the adaptive immmune response
• Pathogens are attenuated to reduce their viruelnce to eliminate key virulence factors
• By establishing an active infection, they stimulate a more comprehensive immune response
• The disadvantage associated with live attenuated vaccines inclde long-term storage and the potential to develop the disease
  Eg. BCG, yellow fever, typhoid + smallpox

Reversion of live polio vaccine is known to occur

Question 3

Inactivated vaccines

Answer 3

• The whole pathogen has been inactivated
• The inactivation process can’t affect the structure of key antigens
• Resulting immune response is weaker and less comprehensive

Eg. cholera, HepA, influenza and rabies

Question 4

Subunit vaccines

Answer 4

• Only expose the invidual to a weakened or dead pathogen
• They are produced by either chemically degrading a pathogen and isolating its key antigens or producing them through genetic engineering

1. Identify the key protective components
2. Isolate the genes encoding these components
3. Produce the components using genetic engineering
4. Use genetic engineering to produce F1 and V antigens in E.coli

Eg. Hep B, anthrax, meningitis, pneumonia + HPV

Question 5

Naked DNA vaccine

Answer 5

• Identify and produce gene coding for vaccne component into a recombinant plasma vaccine
• The introduction of the DNA vaccine into a patient leads to the uptake of the recombinant plasmid by some of the patients cells