Vaccines - Bacterial & Viral Flashcards
Men B Vaccine - describe administration
All new born babies
2 and 4 months; Booster 12 months
Catch up programme for babies born after 1ST May 2015
Bexsero® Components
- outer membrane vesicles (OMV) - N. meningitidis group B strain Z98/254 menZB
- Surface proteins (non-variant) of the bacteria – recombinant :
• Factor H Binding Protein (fHbp)
• Neisseria Heparin Binding Antigen (NHBA)
• Neisseria Adhesin A (NadA)
Men B Vaccine - issues
Other groups remain vulnerable – cost effectiveness, shortages of supply, JCVI
more reactogenic;
not all serotypes of group B covered (unlike menC)
Some cross-protection against menW
£75 per dose – needs to be £20 for cost effectiveness.
88% efficacy and strain coverage
Duration of protection – 10 years
Men ACWY - define
Highly virulent invasive strain W
Haemophilus influenza type B - define
Paediatric disease - usually 6 mo - 3 yrs 1/600
Initially, a nasopharyngitis (often starting with viral infection)
Haemophilus influenza type B - describe spread
spreads to an otitis media,
sinusitis, bronchitis, pneumonia or
sometimes epiglottitis (requiring a
tracheotomy):- croup
Spreads : bacteraemia,
septic arthritis,
meningitis (60% cases)
Haemophilus influenza type B - effect if not treated
Neurological disorders (33%) or death (5%) if not vigorously treated
Haemophilus influenza type B - describe treatment
Vaccine effective: (99% cases are type b)
type b - capsule polysaccharide linked to conjugate:-
diphtheria/tetanus toxoids + outer membrane proteins
Diphtheria - define
Corynebacterium diphtheriae
Pharynx - non-invasive multiplication
Toxin produced locally but acts at a distance
Diphtheria - describe effects
- absorbed by lymphatics – systemic effects
damages heart, kidney, nerves, adrenals- kills epithelial cells and polymorphs
gelatinous exudate - ulcer - necrotic exudate - Pseudomembrane
- local inflammation ,swelling, lymph nodes - Bull Neck
- Respiratory obstruction
- kills epithelial cells and polymorphs
Clostridium tetani - define
Clostridium tetani Gram +ve rods,
terminal drumstick spores
anaerobe
Soil dweller
synaptobrevin - enzyme
Tetanospasmin
Zn2+ endopeptidase
for synaptobrevin
Neurotoxins
Clostridium tetani and tetanus - effect
Blocks release of
inhibitory transmitters-
GABA and glycine
Unopposed continuous
excitation
Whooping Cough – Pertussis - define
Multi-toxin disease
Whooping Cough – describe action of old vaccine
DTaP vaccine
Whole cell vaccine - killed organisms toxicity ?
Whooping Cough – describe action of new vaccine
New low risk acellular vaccine
adhesin + pertussis toxoids + outer membrane proteins
Blocks adhesion and neutralises toxin - antibody role
Very effective
Influenza programme - aim
Aim:
To protect those who are most at risk of serious illness
or death should they develop influenza
To reduce the circulation of the virus
Influenza programme - who gets it
Who gets it?
- all those aged 65 years or over
- all those aged 6 months or over in a clinical risk group
- those living in long-stay residential facilities
- those who care for elderly or disabled persons
- household contacts of immunocompromised individuals
- those working within health and social care settings
- those who work in close contact with poultry
- all children 2 – 9 years (most infections and transmission source)
Tetravalent vaccines will contain the following viruses:
• A/Michigan/45/2015 as the H1N1-like component (as last year)
A/Singapore/INFIMH-16-0019/2016 as the H3N2-like component
B/Colorado/06/2017
B/Phuket/3073/2013
Tetravalent vaccines - effective composition
Effectiveness
- variable by year/age group - antigenic drift and shift; - prior exposure; cross-reacting antibodies - Vaccine production issues
Fluenz Tetra - define
Live attenuated Influenza vaccine (LAIV)
Nasal spray
It is a cold-adapted virus
- cannot replicate at body temperature
Fluenz Tetra 2016/17 - describe active ingredients
A/California/7/2009 (H1N1)pdm09-like virus
A/Hong Kong/4801/2014 (H3N2)-like virus
B/Phuket/3073/2013-like virus
B/Brisbane/60/2008-like virus
What is pneumococcal vaccine?
Streptococcus pneumoniae
Pneumococcal Polysaccharide Vaccine PPV23 - for who?
The 23-valent pneumococcal polysaccharide vaccine (PPV)
for at risk adults and children over the age of 2
Children under 2 can’t make a long-lasting protective immune response
to polysaccharide vaccines.
HPV Vaccination - list licensed vaccines
Two licensed vaccines:
Gardasil: protects against HPV 6,11,16,18 - used now
Cervarix: protects against HPV 16,18
HPV Vaccination - subunit
Recombinant capsid L2 protein in Virus-like particles - subunit
HPV Vaccination - schedule
Schedule: Sept 2008 – all 12-13y and 17-18 year old girls 3 doses over 6 months
booster not currently thought necessary - so now 2 doses
HPV Vaccination - results from clinical trials
Clinical trials show high efficacy, well tolerated:
66% reduction in prevalence high grade pre-cancerous lesions
76% reduction in cervical cancer deaths
Will save 400 lives/year
Neonatal tetanus - define
Neonatal tetanus :- Disease of the 8th Day
360,000 deaths/yr
Tetanus toxoid to mother in late pregnancy
→ high titres of maternal IgG in neonate
Neonatal tetanus - why no live vaccine
Don’t want live vaccines during pregnancy - ?damage to foetus
e.g. rubella (MMR)
TdaP/polio - whooping cough - describe use in pregnancy, why, when, uptake rate
- TdaP/polio - whooping cough - Boostrix IPV
In response to the current UK outbreak of whooping cough
pregnant women
-to protect their babies before routine immunisation
28 – 32 weeks stage up to 38 weeks
Introduced in 2012
Uptake rate ~ 70%
Of 18 babies died of pertussis since 2013, 16 were from non-vaccinated mothers
Flu - describe use in pregnancy, uptake rate
Flu - mother and baby protection – earlier the better
Pregnant women = 13% of all H1N1 flu deaths
Most childhood deaths in <6 month-olds
Uptake rate only ~42% in 2015-16; ~70% 2017 in UK
NEW POLICY From 1 September 2005,
to provide an improved targeted BCG vaccination programme for –
• All infants (0 - 12 months) living in areas where the incidence of TB
is 40/100,000 or greater
• All infants (0 - 12 months) with a parent or grandparent who
was born in a country where the incidence of TB is 40/100,000 or greater
at risk secondary school children
Previously unvaccinated new immigrants from high prevalence countries for TB
Explain why no BCG in USA
USA – no BCG comprehensive infection control policies
skin testing not compromised
treatment if PPD +ve
