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Flashcards in Principles of Immunisation Deck (35):
1

What are 2 examples of natural passive immunity?

-placental transfer of IgG
-colostral transfer of IgA

2

What are 2 examples of artificial passive immunity?

-treatment with immunoglobulin
-immune cells

3

What is human normal immunoglobulin?

contains all antibodies- protein extracted from pooled blood donations

4

What is human specific immunoglobulin?

selected blood donor with high antibody titres against a specific organism

5

When is HNIG used for post-exposure prophylaxis?

-hep A
-measles
-polio
-rubella

6

When are specific immunoglobulins used for post-exposure prophylaxis?

-hep B
-rabies
-tetanus
-Varicella-Zoster virus

7

What is an advantage of passive immunity?

gives immediate protection

8

What are the disadvantages of passive immunity?

-short term: no immunological memory
-serum sickness
-graft versus host disease

9

What is an example of natural active immunity?

exposure/infection

10

What is an example of artificial active immunity?

vaccination

11

What are the advantages of active immunisation?

-antigen stimulated immune response
-long term immunity
-immunological memory
-faster and better response on second encounter

12

Vaccination

the administration of antigenic material to stimulate and individual's immune system to develop adaptive immunity to a pathogen

13

Why might someone not receive a vaccination?

-febrile illness
-pregnant woman cannot receive live attenuated vaccines
-allergy
-immunocompromised cannot be given live attenuated viruses

14

How does an immune response occur?

-disease causing organism contains antigens
-antigens stimulate the production of antibodies
-antibodies bind to the organism and lead to its destruction and memory B cells are formed

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How are live attenuated vaccines made?

attenuation of a pathogenic organism by repeated passage in cell culture or a non-human host

16

Advantage of live attenuated vaccines

they elicit strong cellular and antibody responses and often confer lifelong immunity with only one or two doses

17

Disadvantages of live attenuated vaccines

-remote possibility exists that an attenuated microbe could revert to a virulent form and cause disease
-require refrigeration

18

How are inactivated vaccines produced?

by killing the disease causing microbe with chemicals, heat or radiation

19

Advantages of inactivated vaccines

-more stable and safer than live vaccines
-do not require refrigeration

20

Disadvantages of inactivated vaccines

stimulate a weaker immune system response than liv vaccines
-may require and adjuvant
-boosters likely required

21

What are 4 examples of inactivated vaccines?

-bubonic plague
-typhoid
-hep A
-rabies

22

What are acellular vaccines?

use only the antigenic part of the disease causing organism

23

What are the characteristics of acellular vaccines?

-don't induce the strongest immune response
-may require boosters
-cannot cause disease

24

When are toxoid vaccine used?

when a bacterial toxin is the main cause of illness- when bacteria secrete toxins or harmful chemicals

25

How are toxins inactivated?

treating them with formalin

26

What is an example of a toxoid vaccine?

DTaP (diphtheria, tetanus and pertussis)

27

What is a BCG?

a vaccine against Mycobacterium bovis to protect against Mycobacterium tuberculosis

28

What is a subunit vaccine?

-a vaccine that only includes the antigens that best stimulate the immune system
-in some cases they use epitopes- parts of the Ag that Ab or T cells recognise

29

What is a conjugate vaccine?

A vaccine which links antigens or toxoids from the microbe that an infant's immune system can recognise to polysaccharides

30

What problem do conjugate vaccines solve?

-many harmful bacteria have an outer coating of polysaccharides
--polysaccharide coatings disguise bacterial antigens so that the immature immune system of infants and children can't recognise or respond to them

31

What do conjugate vaccines defend against?

-hepB
-hib
-pertussis
-HPV

32

How do DNA vaccines work?

-use only genetic material
-when the genes for a microbe's antigens are introduced into the body, some cells will take up that DNA and some cells make the antigen molecules.
-the cells secret the antigens and display them on their surfaces
-this evokes a strong antibody response to the free-floating antigen secreted by cells
-stimulates a strong cellular response against the microbial antigens displayed on cell surfaces

33

Adjuvant

a substance which enhances the body's immune response to an antigen

34

What is the primary aim of vaccination?

to protect the individual who receives the vaccine

35

How does herd immunity occur?

-Vaccinated individuals are less likely to be a source of infection to others
-this reduces the risk of unvaccinated individuals being exposed to infection
-therefore individuals who cannot be vaccinated will still benefit from routine vaccination programmes