Chapter 13 - Communicable Diseases

Question 1

Definition of Vaccination

Answer 1

Administration of antigens into the body

Question 2

Definition of immunization

Answer 2

Process by which a person develops immunity

Question 3

How do vaccines provide active immunity?

Answer 3

1. Injection of antigens or weakened virus.
2. Immune response
3. Engulfed by phagocytes
4. Phagocyte presents the antigen
5. Clonal selection (t)
6. Clonal expansion (t)
7. T-lymphocytes produce and secrete cytokines
8. Cytokines active B-lymphocytes
9. Clonal expansion (b)
10. B-plasma cells produced and release antibodies
11. B-memory cells produced and remain in the plasma.
    = secondary response is greater

Question 4

Why might boosters be used for vaccinations ?

Answer 4

• ensures high numbers of circulating memory cells

- ensures high concentration of antibodies remain in the plasma

Question 5

Describe the antibody production after vaccination and boosters

Answer 5

• low antibody production after 1st exposure
• higher levels of antibodies after boosters
• because it takes time for clonal selection and expansion to occur
• after boosters, memory cells are stimulated to divide rapidly
• higher number of plasma cells = produce antibodies faster

Question 6

What are the 5 different types of vaccines?

Answer 6

1. Live-attenuated
2. Killed inactivated
3. Toxoids
4. Subunit and conjugate
5. Artificial or recombinant vector

Question 7

What are live attenuated vaccines?

Answer 7

• modified strains of bacteria or virus that have the ability to multiply
• have ability to multiply but not cause the disease or the symptoms

Question 8

Examples of live-attenuated vaccines

Answer 8

• MMR
• polio
• TB
• typhoid

Question 9

Advantages of live attenuated vaccines

Answer 9

• strongest immune response
• stimulates humoral and cellular immune response
• immunity can be passed on = herd immunity
• no adjuvants needed

Question 10

Disadvantages of live attenuated vaccines

Answer 10

• cant be given to people with compromised immune systems
• organism may become pathogenic
• harder to store and transport
• less stable
• more difficult to produce
• more likely to have side effects

Question 11

What are killed inactivated vaccines?

Answer 11

• bacteria or viruses killed by heat or chemical treatment

- antigens are still intact

Question 12

Examples of killed inactivated vaccines

Answer 12

• influenza
• Hep A
• polio
• cholera
• whooping cough

Question 13

Advantages of killed inactivated vaccines

Answer 13

• more stable and safer
• easier to transport
• easier to produce
• no reversion possible

Question 14

Disadvantages of killed inactivated vaccines

Answer 14

• weaker immune response for shorter time
• boosters needed
• needs adjuvant

Question 15

What are toxoids vaccines?

Answer 15

• toxins extracted and treated form formaldehyde
• prevents toxins causing symptoms
• promotes production of antitoxins

Question 16

Examples of toxoid vaccines

Answer 16

• diphtheria

- tetanus

Question 17

Advantages of toxoid vaccines

Answer 17

• safe to use

Question 18

Disadvantages of toxoid vaccines

Answer 18

• may not provoke strong immune response

Question 19

What are subunit and conjugate vaccines ?

Answer 19

• subunit : specific antigens are extracted and injected

- conjugate : antigens are joined to a protein

Question 20

Examples of subunit and conjugate vaccines

Answer 20

• haemophilus influenza type b

Question 21

Advantages of subunit and conjugate vaccines

Answer 21

• can be used to make vaccines to several different strains

- stimulates humoral and cellular immune response

Question 22

What are artificial or recombinant vector vaccines ?

Answer 22

• genes for antigens are transferred to harmless microorganisms

Question 23

Examples of artificial or recombinant vector vaccines

Answer 23

• rabies

- HPV

Question 24

Advantages of artificial or recombinant vector vaccines

Answer 24

• provides immunity to antigens that can’t easily be inactivated or attenuated