Immunization Flashcards
What are the contradictions to vaccines?
• Confirmed anaphylaxis reaction to previous dose of same antigen or vaccine component
• Live vaccines:
– Immunosuppression (primary, radiotx, high-dose steroids/other drugs, HIV)
– Pregnancy
• Egg allergy (yellow fever, flu)
• Severe latex allergy
• Acute or evolving illness – defer till resolved/ stabilised
What is herd immunity?
Protect unvaccinated individuals, through having sufficiently large proportion of population vaccinated
Vaccinated individuals stop transmission of organism
Proportion required to be immune derived mathematically, based on:
Transmissibility and infectiousness of organism
Social mixing btw people in population
Why is herd immunity not useful for tetanus?
As the spores for tetanus would be present in the environment
What if the herd immunity is increased for more than 90%?
less than 1% of the individuals will be affected
What is the basic reproduction number?
everybody is susceptible and ?
What is effective reproduction number?
idk findout
What is crucial to identify the number of new cases formed?
basic reproduction number
What is the Population immunity for disease eradication is dependent on?
Ro
How many diseases are vaccinated for free in kids?
15 diseases
What is the purpose of routine vaccination schedule?
- To provide early protection against infections that are most dangerous for the very young – e.g. whooping cough, pneumococcal, Hib, meningococcal
- To ensure continued protection by providing subsequent immunisations and booster doses before reaching age when risk increases
How is the age at which the vaccine given determined?
- age-specific risk of disease
- risk of complications
- ability to respond to the vaccine
How is the optimal age chosen for scheduling the vaccination?
compromise between risk of disease and level of protection (e.g. MMR)
What happens if a vaccine course in interrupted?
it should be resumed and completed
Why are certain vaccines not given before the age of 1?
as it mgith affect the immunoglobins
MMR effective response
1 yr/old
3 1/2 yr/old
What is the importance of immunological memory?
no need to restart the vaccine
Which vaccines are combined and why?
combined to increase the protective effect
16 month vaccine
Hexavalent (DTaP/IPV/Hib/HepB) Diphtheria Tetanus Pertussis Polio Haemophilus influenza type b Hepatitis B
What is the importance of public health notification?
Legal duty of medical practitioners to notify health board (i.e. Public Health) on clinical suspicion of specified diseases or a ‘health risk state’ posing significant public health risk
notification in writing (including electronic transmission) within 3 days
notification by phone as soon as reasonably practicable if ‘urgent’ (determined by practitioner – based on nature of the disease, ease of transmission, patient’s circumstances, and guidance issued by Scottish Ministers)
which Diseases to be notified by registered medical practitioners, based on REASONABLE CLINICAL SUSPICION Should not await laboratory confirmation
Anthrax *Botulism Brucellosis *Cholera *Clinical syndrome due to E. coli O157 infection *Diphtheria *Haemolytic Uraemic Syndrome (HUS) *Haemophilus influenzae type b (Hib) *Measles *Meningococcal disease Mumps *Necrotizing fasciitis Paratyphoid *Pertussis Plague *Poliomyelitis *Rabies Rubella *Severe Acute Respiratory Syndrome (SARS) *Smallpox Tetanus Tuberculosis (respiratory or non-respiratory) (see Note 2) *Tularemia *Typhoid *Viral haemorrhagic fevers *West Nile fever Yellow Fever
By when should they be notified?
*8 within the same working day
follow/ within 3 days is still required
red
green
black
notify the same day
Which committee is responsible for providing the advice, and looks into the vaccination schedule?
Joint Committee on Vaccination and Immunisation – JCVI
What are the feautres of diphteria?
URTI characterized by sore throat, low grade fever
White adherent membrane on the tonsils, pharynx, and/or nasal cavity
what causes diphtheria?
Caused by aerobic gram-positive bacterium Corynebacterium diphtheriae
Which vaccine covers diphthera?
diphtheria is now covered by the 6-in-1 vaccine, also including tetanus, pertussis, polio, hepatitis B and Haemophilus influenzae type b (Hib)
Which organism causes meningococcal disease?
Invasive infection due to Neisseria meningitidis
What are the symtpons that persist in survivors?
10-15% of survivors can have persistent neurological defects including hearing loss, speech disorders, loss of limbs and paralysis.
Features of meningococcal disease?
Meningococcal vaccines available for serogroups A, C, W, Y135 and now B
Spread by person-to-person contact through respiratory droplets of infected people (close contact)
Incubation period ~3-5 days
Colonisation of nasopharynx common (~10%) important reservoir for disease but not well understood
Two peaks in disease: <5yrs and 15-24yrs
How did meningococcal diseas echange in 1990s?
Increasing numbers of cases
Rising proportion of group C infection
Age distribution shift to older teens/early twenties
Some evidence of clustering
Which vaccine was introduceed to decreases meningococcal disease?
men C conjugate vaccine in 1999
Is memngicoccal ba present in the body?
yupo in the
Why is MEn W increasing in 2014-2015?
men ACWY
How has Men W decreased?
compulsory Men ACWY vaccine before coming to uni
How are new vaccines investigated?
phase I, II, and III
Explain the 3 phases of vaccine investigation?
Phase I - is it safe (any major issues) ?
- is it immunogenic ?
Phase II - how reactogenic is it ?
- what dose should be used ?
- how does it compare with current vaccine(s) ?
Phase III - is it efficacious ?
- are there any rarer reactions / safety issues ?
What are the economic cost of the disease?
visits to GP
hospitalisations
What would economic costs of vaccination be?
vaccine costs
adverse events
opportunity costs
Acceptibility of vaccines?
Decision to use or not is based on considering
balance of benefits and risks
Disease burden before vaccination vs known risk of vaccine
Benefit / risk ratio often hugely in favour of vaccine
What is the uptake of immnisation dependent on?
perception of relative risks and benefits
When is uptake measures?
diff times:
1 year
2 year -
Benefits of immunization for an individual?
Reduce burden of disease
acute infection
death
long term complications
Maintain underlying health heart disease asthma transplants cancer treatments diabetes eyesight
What is the benefit of immunization for a society?
Reduce community transmission
-minimise spread of infection
Reduce healthcare utilisation
- GP consultations
- Outpatient clinics
- Hospitalisations
- Ongoing care
Tackle inequalties
Reduce societal burden:
- time off work
- education and learning
- care settings
- -quality of life
What are th evarious challenegs faced by theimmuzation challenge?
reviews and changes (giving HPV for boys)
Flu
transfer the responsibility of vaccination from GPs to other services
tackle vaccine hesitancy
