VACCINE PREVENTABLE DISEASES (PART 1) CONT'D Flashcards
(33 cards)
GUILLAIN-BARRÉ SYNDROME (GBS)
GBS is an illness that affects the nervous system
* rare – general risk is about 10-20 cases per 1,000,000 people
* characterized by loss of reflexes and symmetric paralysis usually beginning in the legs
* results in complete or near complete recovery in most cases
paralysis in the extremities,
you’re watching out for long term is kind of tingling in my fingers, tingling my toes. That’s progressive. It seems to spread any kind of loss of motion
it can result in complete or near-complete
paralysis but it’s generally completely reversible and treatable we use steroids and time.
It is thought that GBS may be triggered by an infection
* The infection that most commonly precedes GBS is the Campylobacter
jejuni bacteria.
* Other respiratory or intestinal illnesses and other triggers may also precede an episode of GBS, including Cytomegalovirus, Epstein-Barr virus and Mycoplasma pneumoniae
Risk of GBS associated with influenza infection greater
than that of immunization
Recommended to NOT provide influenza immunization
to people diagnosed with GBS within 6 weeks of
previous influenza immunization
OCULORESPIRATORY SYNDROME (ORS)
- These symptoms were subsequently described as Oculorespiratory Syndrome
(ORS).
Case definition of ORS – (onset within 24 hours of immunization) - onset of bilateral red eyes
and/or - respiratory symptoms (cough, wheeze, chest tightness, difficulty breathing,
difficulty swallowing, hoarseness, or sore throat) with or without facial swelling
Only occurs w flu shots
ORS DECISION TREE
how severe were the ORS symtpoms?
mild –> may receive the influenza vaccine
moderte –> may receive the influenza vaccine
severe –> non-lower resp symptoms –> may receive the influenza vaccine
lower resp symptoms –> case should be reviewed by MOH before receiving subsequent influenza vaccine
INFLUENZA CONTRAINDICATIONS
TIV/QIV (Inactivated)
- < 6 months of age
- Anaphylactic reaction to previous dose of influenza
- Known hypersensitivity to any component of the vaccine with the
exception of egg
- Diagnosed with Guillain-Barré syndrome within 6 weeks of a previous dose of influenza vaccine
- Experienced severe Oculorespiratory Syndrome (ORS) within 24 hours of receiving after influenza immunization should be assessed further prior to immunizing
LAIV (Live-attenuated)
- < 2 years of age
- Anaphylactic reaction to previous dose of influenza
- Known hypersensitivity to any component of the vaccine
- Immune compromising conditions
- Children with severe asthma (or medically attended wheezing in 7 days prior to vaccination.
- Children/adolescents receiving aspirin
EGG ALLERGY AND INFLUENZA VACCINES
Egg allergy - immediate symptoms within 1-2 hours after
exposure, such as urticaria and angioedema, respiratory,
gastrointestinal or cardiovascular symptoms plus
confirmatory allergy tests (skin test or egg-specific IgE).
* Egg allergy is no longer considered a contraindication for
the influenza vaccine
* Egg allergic individuals may be vaccinated against
influenza using TIV/QIV/LAIV, without a prior influenza
vaccine skin test and using the full dose, irrespective of a
past severe reaction to egg
* Flucelvax – Is grown on mammalian cell culture which uses
no egg in its production
INFLUENZA
VACCINATION
IN CHILDREN
Children less than 9 who are receiving the
Influenza vaccine for the first time will
receive 2 doses 1 month apart.
* If do not return for a second dose will only
receive one dose next year
* The First dose is considered a priming dose
* Would just mean no protection for that first
year
- Okay. So the next year we’re just going to give them one dose, and they’re going to be protected. All it means is last year, when she got her first dose, her child is either sub optimally or not protected at all.
SARS-COV-2
- RNA virus (Coronaviridae family)
- Includes MERS-CoV(MERS), SARS-CoV-1 (SARS)
- Transmission: primarily by droplets spread through coughing, sneezing or talking; lesser degree via contaminated surfaces
- Common symptoms – fever, cough, shortness of breath (additional symptoms
= include weakness, fatigue, nausea, vomiting, diarrhea, changes to taste and smell) - Complications include impaired function of the heart, brain, lung, kidney and coagulation system
- Long COVID?
- ~17-35% of hospitalized patients treated in an ICU
LONG COVID OR POST COVID CONDITIONS
- Include a wide range of symptoms that can potentially last weeks to years post
exposure - Financial burden of these patient sis not yet well understood
- More common in those who had severe COVID
- Some data suggest that those vaccinated who get COVID may be less at risk
- Symptoms
- Fatigue that interferes with daily activities
- Symptoms worsen with physical or mental activity
- Fever
- Cough with shortness of breath
- Chest pain
- Heart palpitations
- Headaches
- Sleep problems
- GI issues
- Joint and muscle pains
COVID VARIANTS
- Variants are a concern with ongoing widespread infection.
- Many cases increase the risk of mutation
- Well over 100 new variants were isolated in 2022 alone
- What we watch for are variants that impact:
- Transmissibility
- Immunity to vaccines
- Infection Severity
- WHO divides variants into:
- Variants of concern
- Variants of interest
COVID-19
VACCINES
Emerging infectious diseases have stressed the need for
novel development and manufacturing platforms that
can be readily adapted to new pathogens
Vaccine development has focused predominantly on the
viral structural spike (S) protein of SARS-CoV-2
Facilitates entry into the cell and is
located on the surface of the virion
Was identified within weeks of first
identification of cases
VACCINE DEVELOPMENT
- Over 242 vaccine candidates are still in development worldwide (as
of Dec 2 2022) - 50 vaccines approved for use in a variety of countries
- Variety of different platforms used worldwide
- 1 DNA vaccine
- 19 Protein Subunit
- 9 mRNA
- 11 inactivated
- 9 non replicating viral vector
- 1 virus-like particle
- mRNA most common vaccine used in North America
COVID-19
VACCINE
PLATFORMS
classcial platforms
next-generation platfroms
hey’ve got whole and activated vaccines that they use it’s very similar to the original polio vaccine. We have live attenuated vaccines which are similar to the Mmr ones
protein ones, which are very similar to our flu one
Virla vector is newer - basically cold virus, and they suck all the genetic material out of it. They they insert into it the genetic material for sars, and so your body gets infected with the adino virus. But when it does all it does, this ends up producing the spike protein, much like the Mrna vaccine, and you build up protection that way.
COVID
VACCINES
IN CANADA
Pfizer-BioNTech mRNA vaccine
*bivalent booster dose (Pfizer-BioNTech
Comirnaty® Original and Omicron
BA.4/BA.5 in individuals age 5 years
and older
*bivalent booster dose (Pfizer-BioNTech
Comirnaty® Original and Omicron BA.1
in individuals age 12 years and older
Moderna mRNA vaccine
primary series in 6 months and
older and 18+ for booster
*Bivalent COVID-19 vaccine
(Original/Omicron BA.4/5)
*Bivalent COVID-19 vaccine
(Original/Omicron B.1.1.529 (BA.1))
AstraZeneca Vaxzevria viral
vector for 18 plus 2 doses
Janssen Jcovden viral vector for
18 plus (note is 1 dose only)
Medicago Covifenz plantbased virus-like particle for 18-
64, 2 doses
Novavax Nuvaxovid Protein
based vaccine 12+ primary
series (2 doses) and 18+ for
booster dose (1 dose)
IMMUNOGENICITY
- Neutralizing Ab titers (NtAb) is the most common correlate of
protection - Results of monoclonal Ab studies support the strong correlation
between NtAb and protection from the virus - Target is the spike protein regardless of vaccine type
- In studies NtAb titers above 160 in convalescent patients
- mRNA vaccines give titers in range of 360-654
- Various other vaccines give titers in the range of 50-300
comparison
2 doses of the vaccine are highly productive against the delta variant.
from 2 doses of vaccine it was super effective over 80%, reducing all hospitalizations and hospitalizations related to the Delta virus.
So people who have a shorter interval. So 3 to 4 weeks the vaccine was not necessarily as effective for them. Where, if we go out to people having the vaccine 16 plus weeks apart, was 93% effective.
eople who are at high risk
probably better get them vaccinated really quickly, and get them to doses really quickly, but lower risk people. We might want to stretch it out for low risk ppl
ote is the adverse effects is that they’re like 95% mild to moderate local like most of the side effects from these vaccines are like a flu shot. They’re going to have a reaction at the site. They’re going to have minor fever
NACI COVID RECOMMENDATIONS
pregnancy ro breastfeeding
NACI recommends that the COVID-19 vaccine should be offered to
individuals in the authorized age group without contraindications to
the vaccine.
* For moderately to severely immunocompromised adults who have not yet been immunized, it is recommended a primary series of 3 doses of an mRNA vaccine should be preferentially offered. For these individuals who have previously received a 1- or 2-dose COVID-19 vaccine, it is
recommended that an additional dose of an mRNA COVID-19 vaccine
should be offered.
- Pregnancy/Breastfeeding:
- Infection in pregnancy may increase the risk of complications requiring hospitalization and intensive care, as
well as poorer pregnancy outcomes including premature birth, stillbirth, and caesarean delivery. - During pregnancy, an mRNA vaccine is preferred due to reassuring published data on the safety of these
vaccines in pregnancy. However, the protein subunit COVID-19 vaccine or VLP COVID-19 vaccine may be
offered to individuals in the authorized age group without contraindications to the vaccine who are not able
or willing to receive an mRNA COVID-19 vaccine.
NACI COVID RECOMMENDATIONS cont’d
- NACI recommends COVID-19 vaccine may be offered to
individuals in the authorized age group without
contraindications to the vaccine who have had
previously PCR-confirmed SARS-CoV-2 infection. - NACI continues to recommend that bivalent Omicron-containing mRNA COVID-19 vaccines are the preferred booster products for the authorized age groups.
- Going forward, any of the bivalent Omicron-containing mRNA boosters are preferred over the original formulation boosters for authorized age groups (18 years of age and older for
Moderna bivalent vaccines and 12 years of age and older for Pfizer-BioNTech bivalent vaccines). - NACI recommends that for individuals 6 months of age and older, COVID-19 vaccines may be given concurrently (i.e., same day), or at any time before or after, non-COVID-19 vaccines (including live and non-live vaccines).
NACI COVID RECOMMENDATIONS
- NACI recommends that a booster dose of a Pfizer-BioNTech Comirnaty (10 mcg) COVID-19
vaccine may be offered ≥6 months after completion of a primary series or previous SARSCoV-2 infection to all children 5 to 11 years of age who do not have underlying medical
conditions that could place them at higher risk of severe illness due to COVID-19. - NACI recommends that a booster dose of a Pfizer-BioNTech Comirnaty (10 mcg) COVID-19
vaccine should be offered ≥6 months after completion of a primary COVID-19 vaccine series
or previous SARS-CoV-2 infection to children 5 to 11 years of age with an underlying
medical condition that places them at high risk of severe illness due to COVID-19 (including
those who are immunocompromised and who received a 3-dose primary series).
MRNA VACCINE MYTHS
- “The vaccine was developed too fast!”
- mRNA vaccines have been in the works for years. Only the massive funding and urgency allowed them to cut out time between research stages. mRNA vaccines are also much easier to design and roll out than traditional vaccines.
- “mRNA vaccines change your DNA!”
- mRNA is simply a message that your body reads. Your cells produce millions of mRNA
strands every day. They cannot insert into your DNA and cannot even enter the nucleus.
*“Pfizer director admits ‘vaccine’ wasn’t tested for transmissibility.” - Vaccines were not required to test for this when being developed. It would of added
time to a process that was already under pressure. The focus was on preventing
illness, hospitalization and death. It only makes sense that if you reduce infection rates transmission will also drop. Some studies in Israel and the UK did show a significant reduction in transmission (>75%) - “mRNA vaccines have dangerous components”
- mRNA vaccines are free of preservatives. Contain only the mRNA strand
a phospholipid layer to stabilize and allow absorption and PEG salts and
sugars to make the solution isotonic. There are no fetal cells or other
products as the mRNA is produced in an mRNA fabricator. - “It’s not safe until we have more long-term data!”
- With billions of people vaccinated, many having been vaccinated
almost a year ago with no issues. The mRNA itself is gone from your
system 2-6 weeks after injection.
HEPATITIS A (HAV)
- RNA virus (Picornaviridae family)
- Transmission: fecal-oral route
- Incubation period: average 28 days
- Cases are infectious 2 weeks before the onset of symptoms until 1 week after onset of
jaundice - Severity of illness increases with age (range from asymptomatic to mild illness to severe
disabling disease lasting several months) - Children < 6 years commonly asymptomatic
- 25% of adult cases hospitalized
- Case fatality rate ~0.5%
- NOT associated with chronic hepatitis or carrier states
- Natural infection confers immunity
- Infants and children can shed virus for up to 6 months after infection.
- Virus can survive in the environment for extended periods in harsh conditions
HAV VACCINE
- Vaccine introduced in 1996
- Available as separate and in combination vaccines
- Inactivated; adsorbed to aluminium hydroxide adjuvant
- Efficacy:
- Immunogenicity – protective concentrations of Ab after 1 dose is 95% to 100% (nearly 100%
seroconvert after 2 doses) - Pre-exposure – 90% to 97% effective in preventing clinic HA illness
- Post-exposure –protective efficacy ~80% if used within 1 week of exposure
- Preparations available:
- AVAXIM®(adult) and AVAXIM®–Pediatric
- HAVRIX®1440(adult), HAVRIX®720 Junior
- TWINRIX® and TWINRIX® Junior (adult and pediatric; combined hepatitis A and hepatitis B)
- VAQTA®
- ViVAXIM® (combined typhoid and hepatitis A)
- Route: IM
- Series: 1 dose for primary immunization; booster dose 6 to 36 months later
HAV VACCINE
RECOMMENDATIONS
- Recommendations for use:
- Pre-exposure: persons 6 months of age and older at increased risk of infection
or severe HA - Example: Travel
- Post-exposure: offered to household and close contacts of proven or
suspected cases of HA (e.g., group childcare centres, clients of infected food
handlers) - Vaccine should preferably be given as soon as possible, and ideally within
14 days - Can be considered if > 14 days since last exposure (no data on outer limit
of efficacy) - Immunoglobulin recommended for infants < 6 months of age, people for
who vaccine is contraindicated and if HA vaccine is unavailable
HAV PROVINCIAL FUNDING (ALBERTA) FOR PRE-EXPOSURE
Must meet eligibility criteria
* Chronic liver disease (hepatitis B or C carriers)
* Candidates or recipients of liver transplants
* Residents of communities with high rates of hepatitis A infection
* Households or close contact of children adopted from hepatitis A
endemic countries
* Lifestyle risks (MSM, illicit drug use)
* Zookeepers, veterinarians and researchers who handle primates
* Residents and staff of institutions for the developmentally challenge in
which there is evidence of sustained hepatitis A transmission
PRE-IMMUNIZATION SEROLOGY FOR ANTIHAV (IGG)
- Considered for:
- Individuals born prior to 1945
- Individuals from an endemic country
- People with history of hepatitis or jaundice that may have been
caused by HA - Individuals diagnosed with hepatitis B and/or hepatitis C infection
