Vacines - Bacterial And Viral

Question 1

What is neisseria meningitids?

Answer 1

A gram negative bacterium that can cause meningitis and other forms of disease including life threatening sepsis

Six serogrups responsible for almost all diseases in the world:
A
B
C
W-135
X
Y

Has a vaccine - Men C vaccine

Question 2

What are the 2 current MenC vaccines in the UK schedule/

Answer 2

HiB/MenC combined vaccine (Menitorix)
- given at 1 year
- MenC is conjugated to TETANUS toxoid

Men ACWY (Menveo, Nimenrix)
- given at 14 years
- Menvo = polysachaarrides from A,C,W135, Y conjugated to diphtheria toxoid
- Nimenrix = they are conjugated to tetanus toxoid

Question 3

Why is it difficult to develop a MenB vaccine?

Answer 3

Because the polysacharride too similar to that on some human cells

A vaccine was developed in 2015
- not worth financial cost and risks of vaccination
- free outrage cost analysis was done again and the vaccine was approved as worth introducing

Question 4

What is the MenB vaccine (Bexero)?

Answer 4

Made from 3 major proteins on the surface of most meningococcal bacteria, combined with outer membrane of 1 MenB strain

Produced in E. coli cells by recombinant DNA technology

Absorbed on aluminium hydroxide

Approved September 2015

Question 5

What is haemophilia influenzae?

Answer 5

99% Type B

Gran negative bacteria - a bacterial meningitis

Paediatric diseases - 6 month - 3 years

Can lead to Arthuritis or meningitis

Question 6

What is the HiB vaccine?

Answer 6

Vaccine for type B haemophilia influenza

Type B capsule polysacharriide linked to conjugate
- DIPHTHERIA TOXOIDS
- TETANUS TOXOIDS
- MENINGOCOCCAL OUTER MEMBRANE PROTEINS

Question 7

What is diphtheria?

Answer 7

Caused by bacterial toxins from corynebacterium diphtheriae

Inhibits protein synthesis in eukaryotes

Grows in the pharynx, larynx and nose - non-invasive so does not spread

Toxin produced locally but acts at a distance
- absorbed by lymphatics = damages heart, kidney, nerves, adrenals
- forms a gelatinous exudate kills epithelial cells and polymorphs
- forms a necrotic exudate = ulcers form

Question 8

What is the vaccine for Diphtheria toxin?

Answer 8

DTaP or dTaP

Diphtheria toxin is treated to make toxoid which is not toxic but immunogenic

Combined with albumin salts adjuvant

Given as a combined vaccine DTaP (higher amount of toxoid) or dTaP

Question 9

What is tetanus?

Answer 9

Caused by a toxin released from clostridium tetani

Gram positive rods - soil dweller - anaerobe

Tetanus toxin is a neurotoxin that inhibits release of neurotransmitters from inhibitory inferons, which interact with motor neurones - Violent spastic paralysis

Question 10

What is the vaccine for Tetanus?

Answer 10

DTaP and Tdap

Tetanus toxoid is treated to convert it into a toxoid, loss of toxicity but not immunogenicity

Combined with aluminium salt adjuvant

Question 11

what is whooping cough (Pertussis)?

Answer 11

Caused by bordetella pertussis - release pertussis toxin which is a virulence factor in pathogenesis

Profound leukocytosis (rise in WBC)

A cough lasting weeks often with “whoop noise”

Can result in death, especially in newborns

Bacterium adheres to ciliated epithelial cell in upper Respiratory tract and multiples - may decend to lungs in infants

Question 12

What is the vaccine for whooping cough-pertussis?

Answer 12

DTaP vaccine

Contains:
pertussis toxoid,
filamentous haemoglutinin,
pertactin (promotes adhesion to cells)

Blocks adhesion ad neutralises toxin

Question 13

Who is given the influenza vaccine?

Answer 13

• At risk population and key staff (NHS)
• all hose bed 65 years or over
• pregnant women
• all children 2—10 years old

Question 14

What is the aim of the influenza programme?

Answer 14

Protect those who are most at risk of serious illness or death should they develop influenza

Question 15

What are the 3 types of influenza?

Answer 15

A
B
C

A and B most common

Question 16

what causes variation in influenza?

Answer 16

Haemaglutinin - 18 types
Neuraminidase - 11 types

Antigenic drift mutation + selection in surface proteins

Antigenic shift - green reassortment between antgenically different strains producing hybrid progeny

Question 17

What is the flu vaccine composed of?

Answer 17

Usually are quadravalant - containing 2 sub-types of influenza A and 2 sub-types of influenza B

Vaccine will change every year based on WHO recommendation for predominant circulating strains

Grown in embryonated hen eggs or in cell culture and are inactivated - all but one vaccine in the UK are inactivated

The one live vaccine is Fluenz tetra - given as a nasal spray and attenuated so that is only replicated in the cold (in nasal passages but not rest of the body

Question 18

What determines the effectiveness of the influenza vaccine?

Answer 18

Variable by year/age group

Antigenic drift an shift

Manufacturing issues can occur

Question 19

What is pneumococcal infection?

Answer 19

Caused by streptococcus pneumoniae

Question 20

What is a invasive disease?

Answer 20

Where the bacterium can be isolated from blood or fro another location which is normal sterile

Question 21

What is the pneumococcal polysaccharide vaccine PPV23?

Answer 21

A polysacharrde vaccine

Polysaccharides from 23 stereotypes used in vaccine (PPV) for at risk adults and children over the age of 2

Children under 2 can’t are a long-lasting protective immune response to polysaccharide vaccine - NEED. CONJUGATED VACCINE

Question 22

What is Pneumococcal conjugate vaccine: PCV 13?

Answer 22

Polysaccharides from 13 most common capsule types

Conjugated to diphtheria toxoid

Question 23

What is the human papillomavirus HPV?

Answer 23

Over 40 types

High risk types (16,18) - lead to cervical cancer

Low risk types (6.11) - genital warts

Question 24

What are the two licensed vaccines for HPV?

Answer 24

Cervarix: Protects against HPV 16,18

Gardasil: protects against HPV 6,11,16,18 - used now for protection against cervical cancer and genital warts

Clinical trails show high efficacy, well tolerated

Scheduled: 2D she’s offered to Boyd and girls 12–13 years old

Question 25

What is neonatal tetanus?

Answer 25

Disease of the 8th day in some developing countries due to infection of the umbilical chord

Tetanu toxoid vacccine to mother in late pregnancy

Question 26

What are the vaccines approved for pregnant women in the UK?

Answer 26

1. DTaP/dTaP — protect newborn infants from whooping cough
2. Flu - mother and baby protection - earlier the better - baby could be still born or born prematurely if mother has flu

Question 27

How can tuberculosis be diagnosed?

Answer 27

The mantoux test

Tuberculin injected in trader ally and measured after 72 hours

If you have TB or have had TB, memory T cell will be reactivated, cytokines ill be secreted and a local inflammatory response will occur

Red bumble on the skin if the person has TB

Results will have to be interpreted carefully and depend on risk factors of individual

ALSO BE GIVEN CHEST X RAY

Question 28

What two vaccines are not approved in the UK and why?

Answer 28

Tuberculosis vaccine
- from 2005 children no longer have to be vaccinated against TB

Chickenpox vaccine
- vast majority of children recover quickly and easily
- Adult chickenpox is more servere
- therefore allowing children to develop they’re immune response/defence from a young age lessens the effects of contracting chickenpox in adulthood
- being exposed to chickenpox in adulthood boosts your immunity to shingles