Vaccination Flashcards
What are the 7 Cs -antecedents of vaccination?
Confidence in safety of vaccine
Confidence in recommending system
Convenience
Complacency
Calcuation of risk to benefit
Collective responsibility
Conforming socially
What is the definition of immunisation?
Delivery of a vaccine (biological agent designed to train immune response) via oral/IM/nasal route PLUS the immune response
How are herd immunity and the basic reproductive number linked?
Herd immunity threshold is defined as Ro-1/Ro where Ro is the expected number of cases generated by the first case (assuming everyone is susceptible)
Think ‘time’!
How is the basic reproductive number actually calculated?
Number of infected contacts per unit time X infectious time period
What are the 3 key reasons for vaccinating?
- Reduce onwards transmission (indirect effect/herd)
- Reducing acquisition in contacts ‘prophylaxis’ (infection/outbreak control)
- Reducing acquisition in populations (communicable disease control)
What 5 things will impact the indirect (transmission reduction) effects of immunisation?
- Pathogen transmissibility
- Population susceptibility
- Population mixing
- Vaccine efficacy
- Vaccine distribution
Who are the key actors in UK immunisation programmes?
JCVI - Review and recommend
DHSC - Strategic oversight and performance targets
NHS England - Commissions
UKHSA - surveillance
MHRA and manufacturers
What 4 dimensions are used to decide to implement a vaccination strategy?
1.Disease - spread, severity & societal cost
2.Vaccine - SAFE as well as effective, SIMPLE to deliver
3.Logistics - price, training, delivery infrastructure, supply
4.Surveillance & evaluation
5.Public perception - acceptability, perceived risk, communication strategies
What do control and containment mean?
Control - policy creating restriction of circulation of communicable disease (v spontaneous circulation)
Containment - state achieved by effective control whereby an infectious agent is no longer a PH threat
Give me a definition, 2 examples and the pros and cons of live attenuated vaccines
Live but disabled pathogen (e.g. BCG, MMR)
+ves: Can sometimes be given nasally, tends to confer longer-term immune response
-ves: Requires cold storage, ideally 28 day gap if 2+ live vaccines, can induce disease, unsuitable for immunosuppressed
Give me a definition, 3 examples and the pros and cons of inactivated vaccines
- Pathogen is killed, subunit/conjugate, toxoid
- Flu (killed), HPV (subunit), Tetanus (toxoid)
- +ves: no cold storage, give 2+ together, doesn’t induce disease, suitable for immunosuppressed
- -ves: shorter-term immunity conferred
Designing an immunisation programme: what are the 8 features that need designing?
1.Purpose - outbreak/communicable disease control
2. Mass v targeted
3. Active v inactive vaccine
4. Age
5. Dose Intervals and boosters
6. Appropriate registers and communications
7. Logistics (finance, teaching, admin, distribution)
8. Surveillance and Evaluation
The second type is split into 2
What 2 types of data are used to evaluate vaccination programmes by estimating pre-post immunisation disease burden?
1.Notifiable disease rates
2. Sero-epi surveillance biomarkers of:
A. vaccine
B. infection
How is the ratio of clinical to sub-clinical infections estimated?
Comparing rates of clinical reports of disease with rates of sero-epidemiological markers
When and why is the Respiratory Syncytial Virus vaccine given?
- Since Sept 2024, pregnant women (28 weeks) & 75-79 year olds (plus catch-up programme)
- requires fridge though inactivated!
- Given because: worse than flu for GP, A&E, admissions and deaths
- Rising rates in infants and young children
When and why is the HPV Vaccine given?
- Single dose to boys and girls aged 12-13
- GBMSM at risk
- Protects against 9 strains of HPV - indirect and direct effects, cervival cancer control, oropharyngeal cancer (GBMSM)
What have been the key changes to the HPV Vaccination programme and why?
2008 Started
2014 3 - 2 dose (sufficient antibody response)
2015 expanded to GBMSM
2019 expanded to boys after JCVI decline in 2017 (changed parameters to accommodate long natural history and consider genital warts)
2023 Switch to 1-dose ‘Gardasil 9’
What are the 4 main pregnancy vaccines?
Seasonal flu
COVID19
Pertussis at 20 weeks
RSV at 28 weeks
What are the 4 main older age vaccines?
Seasonal flu and shingles (65+)
Pneumococcal (65+)
RSV - 75 years
COVID19 (65+)
What are the 7 childhood vaccine timepoints?
- 8, 12, 16, 52 weeks
- 3 ys 4m
- 12-13 years
- 4 years
Which vaccinations are given at 3ys 4m, at 12-13 years and at 14 years?
- MMR (3 years 4m)
- Tetanus, Diptheria & Polio and Pertussis (3 years 4m)
- HPV (12-13 years)
- MenACWY (14 years)
- Tetanus Diptheria & Polio (14 years)
3 given at 1 year and
What vaccinations are given between 6-52 weeks?
- Before 1 year- Pertussis, Diptheria, Tetanus, Polio, Hib, Hep B, Rotavirus, PCV (pneumococcal)
- 1 year - Hib, MenC, MMR
