Immunization Background & Principles Flashcards
Who are routines vaccinations recommended for?
children, adolescents, and adults against vaccine-preventable diseases
-aka recommended for all
additional vaccinations for individuals at high-risk
What is the goal of immunization programs?
protect individuals & communities from disease
prevent, control, and/or eliminate transmission
saves lives and money
What are some relevant national and provincial guidelines to refer to for vaccine information?
National Advisory Committee on Immunization (NACI)
Canadian Immunization Guide (CIG)
Saskatchewan Immunization Manual (SIM)
Saskatchewan Immunization Services
medSask
When are some good times to check-in regarding immunizations?
with annual flu vaccine or COVID-19 vaccine
review of chronic medical conditions/med reviews
new diagnosis/Rx -e.g. MS, RA, IBD and starting IS therapy
request for prenatal vitamins
when dispensing medication for an infection
other: travel
What is an immunogen/antigen?
the substance that stimulates or triggers an immune response
What is an immunoglobulin/antibody?
proteins produced in response to antigens which protect the body from disease
What is a vaccine?
highly regulated, complex biological product designed to induce a protective immune response
Differentiate the adaptive and innate immune system.
adaptive: develops as a result of infection or immunization
-defends vs a specific pathogen
-immunology memory
innate: physical barrier; does not provide immunologic memory
What is herd immunity?
can be established by adequate vaccination rates
required to prevent person-to-person transmission of infectious diseases
indirectly protects individuals
-unvaccinated/under vaccinated (e.g. infants)
-unable to mount a robust immune response to vaccines (e.g. immunosuppressed)
What percentage of the population needs to be vaccinated to achieve herd immunity?
each vaccine preventable diseases requires a different % of the population to be vaccinated to achieve herd immunity
-diseases that are highly transmissible (e.g. measles) require a higher % of the population to be vaccinated
What are the different types of vaccines?
one immunizing antigen vs one disease
-“monovalent” (ex: Hep A)
multiple immunizing antigens vs more than one serotype of the same disease
-“bivalent, trivalent, quadrivalent”
immunizing antigens vs more than one vaccine preventable disease
-measles, mumps, rubella +/- varicella vaccine (MMR/MMRV)
-diptheria, tetanus, pertussis vaccine (DTaP)
Describe live (attenuated) vaccines.
whole, weakened bacteria or viruses that replicates, inducing an immunological response similar to natural infection (but very mild because they are weakened/attenuated)
-long term immunity
-immunity obtained with one dose (2nd dose given to ensure all are protected)
replicating –> very small risk of infection and contraindicated/caution in immunocompromised patients
Describe killed (inactivated) vaccines.
whole parts of an inactivated (killed) bacteria or viruses; toxoids; parts of bacteria or virus obtained via recombinant technology
boosters required to maintain adequate titres after primary series
non-replicating –> cannot cause disease they are designed to prevent
safe for immunocompromised patients
What are examples of live vaccines?
MMR
varicella
MMRV
rotavirus
typhoid (oral)
all other vaccines are inactivated vaccines
What are the components of vaccines?
antigen: infectious agent itself (or piece of it)
suspending fluid (ex: sterile H20, NaCl, culture fluid)
stabilizers (ex: gelatin)
preservatives (ex: thimerosal)
antibiotics: prevent bacterial growth (ex: neomycin)
adjuvants: increase immunogenicity or antigenicity, prolongs antigen absorption (aluminum salts, boostrix)
What is the component of vaccines that cause people to feel more sore and sick?
adjuvants
What are the many factors that affect vaccine response?
viability of the antigen
antigen dose
age
immune status
route & site of administration
timing
vaccine storage
What are the routes of administration for vaccines?
intramuscular
-most; vaccines with adjuvants
subcutaneous
-live vaccines & Polio
oral
-rotavirus, travel vaccines (e.g. cholera, typhoid)
Can multiple vaccines be given at once?
may give multiple vaccines at the same visit
-if possible, give in separate anatomic sites
-if not, separate by > 1 inch
exception:
-live vaccines given on same day or wait > 4 weeks between live vaccines
-pneumococcal vaccines
Can the flu shot and COVID shot be given at the same time?
latest data suggests it can be given at the same time or any time before or after other vaccines in adults and children over 5 years of age
NACI: individuals 6 mo and older may get COVID vaccines concurrently or anytime before/after non-COVID vaccines
Are vaccines interchangeable?
ideally, complete vaccine series with the same product
most vaccines can be used interchangeably to complete series if the vaccine is not available
Which vaccines are not interchangeable?
pneumococcal
some meningococcal
watch out for:
-special populations
-Hep B: dialysis and non-dialysis
-Twinrix
What needs to be done if the vaccine schedule is interrupted?
series does not need to be restarted regardless of time between doses
What are the contraindications to vaccines?
very few true contraindications
-anaphylactic reactions to previous vaccine
-anaphylactic reaction to egg (yellow fever or RABAVERT rabies vaccine)
-pregnancy, immunocompromised (live vaccines)
-Guillan-Barre syndrome < 6 weeks of immunization
-anaphylactic reaction to neomycin (IPV, MMR)
-anaphylactic reaction to gelatin (MMR, varicella)
caution: bleeding disorder
Can vaccines be given if someone has an URTI?
can be given in mild URTI with/without fever
Describe the risk of vaccines causing GBS.
associated with tetanus and influenza vaccine
influenza: ~ one excess GBS case per 1 million vaccine doses
risk if higher following wild type influenza infection
What is an acronym to help remember how to manage anaphylaxis in a community pharmacy setting?
CAPE
-call 911
-assess ABCs, skin changes, GI symptoms, mental status
-position on back and elevated lower extremities
-inject epinephrine
What is the Public Health Agency of Canada and Canadian Paediatric Society’s statement on egg allergies and vaccines?
certain vaccines (MMR), influenza (all types), varicella, rabies contain such small amounts of egg protein (which is also denatured) that they are safe for routine use in patients with egg allergy
What are the expected adverse effects of vaccines?
local:
-tenderness, redness, swelling, pain at injection site
systemic:
-fever, irritable (peds), drowsiness, decreased activity, decreased appetite, syncope
relatively common, predictable, and self-limiting AEs
Which adverse reactions thought to be caused by a vaccine need to be reported?
minor/expected rxns do not need to be reported
serious/rare/unexpected AEs thought to be cause by vaccine = fill out AEFI form
What are some distraction techniques that can be tried during vaccination?
deep relaxation breathing
use technology
shift attention/pay attention to another body part
rapid fire questions
What are some pain management strategies for vaccinations?
procedural:
-inject the most painful vaccine last
-give non-dominant arm
physical:
-breastfeed (< 2 y)
-skin to skin contact (< 1 mo)
positioning:
-holding, patting, rocking (< 3 y)
-sit up (> 3 y)
pharmacologic:
-topical anesthetics (< 12 y)
-sucrose solution (< 2 y)
process:
-educate about pain management the day before or day of
-parents should be present if < 10 y
How should the rotavirus vaccine be given?
the vaccine is sweet-tasting; usually given 1st & no additional sweet tasting solution is required
Which vaccines are associated with more injection site pain?
Prevnar-20
MMR II
HPV vaccines
Should oral analgesics be given to children prior or at the time of vaccination to reduce pain?
CIG: administration of oral analgesics (ibu or acet) to children to reduce pain prior to or at the time of injection is not recommended
-no evidence of benefit
-concern that antipyretics may reduce immune response
-can give in first 1-2 days post vaccine if required for pain/fever
What are the drug interactions of vaccines?
immunosuppressants (e.g. DMARDs, prednisone > 20mg/d x 2 wks):
-killed: give > 2 wks before starting therapy if possible but safe to give while on therapy
-live: give > 4 wks before starting therapy if possible or delay until tx is dc +/- waiting period
antithrombotics:
-caution, bleed risk
