ppt - Komion

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Transcript ppt - Komion

Immunisation
1796
If you understand basic
immunology you can explain...
• How vaccines work and why vaccine
failures occur
• Adverse events and their timing
• Why the schedule is as it is
• Why vaccines cannot overload the
immune system
Physical barriers
• Skin – 2 m²
• Mucosal membranes – digestive,
respiratory, reproductive tract –
400 m²
Innate immunity
Phagocytosis
Macrophage - WBC
Rapid action 0-4 hours
Non-specific – same response each time
No memory – same response at each
encounter
• May destruct the antigen
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Adaptive immunity
• Second level of defence
• Effectiveness increases with each
encounter
• Specific immune response
Types of (adaptive) immunity
• Active Immunity
• Passive Immunity
Passive Immunity
• Transfer of
maternal
antibodies
• Administration of
antibodies
Active Immunity
• Antibodies
produced in
response to an
infection
• Antibodies
produced in
response to a
vaccination
Types of antibody
• IgG – the only type that crosses the
placenta (after 32 weeks)
• IgA – in breast milk – gives some
mucosal protection
• IgE – over production associated with
anaphylaxis
• Also IgM – maybe further reading!
Active versus passive
immunity
• ACTIVE
• PASSIVE
• Long lasting
• Only short term
• Takes time to be
effective
• Immediate
protection
• http://www.nhs.uk/Video/Pages/Vaccinationa
nimation2.aspx
Vaccination schedule 2015
Age
Diseases protected against
2 months Diphtheria, tetanus, whooping cough, polio, Hib, pneumococcal disease
Rotavirus (Men B from Sept 2015)
3 months Diphtheria, tetanus, whooping cough, polio, Hib, meningococcal disease
type C and Rotavirus
4 months Diphtheria, tetanus, whooping cough, polio, Hib, pneumococcal &
(Men B from Sept 2015)
12-13
months
Hib/meningococcal disease type C
pneumococcal disease
Measles, mumps & rubella (MMR) and (Men B from Sept 2015)
2,3 &4yrs Children’s flu vaccine
3yrs 4m
Diphtheria, tetanus, whooping cough, polio
MMR (pre-school immunisations)
12-13yrs
HPV (cervical cancer) girls only 2 x doses 6 months apart
13-18yrs
Diphtheria, tetanus, polio (school leavers immunisations)
Men ACWY
17
Vaccine overload?
Part of body
Bacteria
Scalp
1,000,000/cm2
Surface of skin
1000/cm2
Saliva
100,000,000/g
Nasal mucus
10,000,000/g
Faeces
Over 100,000,000/g
Contraindications
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Immunosuppression & treatment
Some steroid use
Unstable neurological condition
Previous anaphylactic reaction
Care with live vaccines
• Pyrexia
• Acute illness
• Side effects??
Vaccine trials
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Pre-clinical laboratory based work
Phase I – (small scale – adults)
Phase II – (population specific)
Phase III – (100s-1000s participants)
Phase IV  vaccines – MHRA reporting
Getting to the schedule
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Research and development
JCVI
Recommendations to DH
Cost and feasibility studies
Supply and delivery
Awareness and training issues
References/further reading
• Immunisation against infectious disease
(Green Book) [online]
https://www.gov.uk/government/organisation
s/public-health-england/series/immunisationagainst-infectious-disease-the-green-book
• Public Health England website
https://www.gov.uk/government/organisation
s/public-health-england