Immunization Background & Principles

Question 1

Who are routines vaccinations recommended for?

Answer 1

children, adolescents, and adults against vaccine-preventable diseases
-aka recommended for all
additional vaccinations for individuals at high-risk

Question 2

What is the goal of immunization programs?

Answer 2

protect individuals & communities from disease
prevent, control, and/or eliminate transmission
saves lives and money

Question 3

What are some relevant national and provincial guidelines to refer to for vaccine information?

Answer 3

National Advisory Committee on Immunization (NACI)
Canadian Immunization Guide (CIG)
Saskatchewan Immunization Manual (SIM)
Saskatchewan Immunization Services
medSask

Question 4

When are some good times to check-in regarding immunizations?

Answer 4

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

Question 5

What is an immunogen/antigen?

Answer 5

the substance that stimulates or triggers an immune response

Question 6

What is an immunoglobulin/antibody?

Answer 6

proteins produced in response to antigens which protect the body from disease

Question 7

What is a vaccine?

Answer 7

highly regulated, complex biological product designed to induce a protective immune response

Question 8

Differentiate the adaptive and innate immune system.

Answer 8

adaptive: develops as a result of infection or immunization
-defends vs a specific pathogen
-immunology memory
innate: physical barrier; does not provide immunologic memory

Question 9

What is herd immunity?

Answer 9

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)

Question 10

What percentage of the population needs to be vaccinated to achieve herd immunity?

Answer 10

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

Question 11

What are the different types of vaccines?

Answer 11

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)

Question 12

Describe live (attenuated) vaccines.

Answer 12

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

Question 13

Describe killed (inactivated) vaccines.

Answer 13

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

Question 14

What are examples of live vaccines?

Answer 14

MMR
varicella
MMRV
rotavirus
typhoid (oral)
all other vaccines are inactivated vaccines

Question 15

What are the components of vaccines?

Answer 15

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)

Question 16

What is the component of vaccines that cause people to feel more sore and sick?

Answer 16

adjuvants

Question 17

What are the many factors that affect vaccine response?

Answer 17

viability of the antigen
antigen dose
age
immune status
route & site of administration
timing
vaccine storage

Question 18

What are the routes of administration for vaccines?

Answer 18

intramuscular
-most; vaccines with adjuvants
subcutaneous
-live vaccines & Polio
oral
-rotavirus, travel vaccines (e.g. cholera, typhoid)

Question 19

Can multiple vaccines be given at once?

Answer 19

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

Question 20

Can the flu shot and COVID shot be given at the same time?

Answer 20

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

Question 21

Are vaccines interchangeable?

Answer 21

ideally, complete vaccine series with the same product
most vaccines can be used interchangeably to complete series if the vaccine is not available

Question 22

Which vaccines are not interchangeable?

Answer 22

pneumococcal
some meningococcal
watch out for:
-special populations
-Hep B: dialysis and non-dialysis
-Twinrix

Question 23

What needs to be done if the vaccine schedule is interrupted?

Answer 23

series does not need to be restarted regardless of time between doses

Question 24

What are the contraindications to vaccines?

Answer 24

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

Question 25

Can vaccines be given if someone has an URTI?

Answer 25

can be given in mild URTI with/without fever

Question 26

Describe the risk of vaccines causing GBS.

Answer 26

associated with tetanus and influenza vaccine
influenza: ~ one excess GBS case per 1 million vaccine doses
risk if higher following wild type influenza infection

Question 27

What is an acronym to help remember how to manage anaphylaxis in a community pharmacy setting?

Answer 27

CAPE
-call 911
-assess ABCs, skin changes, GI symptoms, mental status
-position on back and elevated lower extremities
-inject epinephrine

Question 28

What is the Public Health Agency of Canada and Canadian Paediatric Society’s statement on egg allergies and vaccines?

Answer 28

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

Question 29

What are the expected adverse effects of vaccines?

Answer 29

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

Question 30

Which adverse reactions thought to be caused by a vaccine need to be reported?

Answer 30

minor/expected rxns do not need to be reported
serious/rare/unexpected AEs thought to be cause by vaccine = fill out AEFI form

Question 31

What are some distraction techniques that can be tried during vaccination?

Answer 31

deep relaxation breathing
use technology
shift attention/pay attention to another body part
rapid fire questions

Question 32

What are some pain management strategies for vaccinations?

Answer 32

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

Question 33

How should the rotavirus vaccine be given?

Answer 33

the vaccine is sweet-tasting; usually given 1st & no additional sweet tasting solution is required

Question 34

Which vaccines are associated with more injection site pain?

Answer 34

Prevnar-20
MMR II
HPV vaccines

Question 35

Should oral analgesics be given to children prior or at the time of vaccination to reduce pain?

Answer 35

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

Question 36

What are the drug interactions of vaccines?

Answer 36

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