immunisation Flashcards
- “The most important investment that any country
can make in the health of it’s children” (WHO) - “With the exception of clean water, no other
modality, not even antibiotics, has had such a
major effect on mortality reduction” (WHO) - Vaccines save up to 3 million lives per year
known as —
immunisation
read;
- Plague of Athens = cause unknown (?Typhoid
fever or Bubonic plague)
– 430 BC, noted the same person never affected twice - China, 10th century (also Turkey and parts of
Africa)
– Variolation: pustules from smallpox patients dried
and inoculated into skin/nasal passages of children
→ protection from future disease - UK Rural knowledge = those who contracted
cowpox were immune to smallpox
– 1796, Edward Jenner used pustules from cows to
immunise people against smallpox
- — = a live or inactivated substance (e.g. protein, polysaccharide) capable of producing an immune
response
– Proteins are more potent immunogens than polysaccharides - —- = protein molecules (immunoglobulins)
produced by B lymphocytes to help eliminate an antigen - — = substance that enhances the antibody response
– Most combination vaccines contain adjuvants like aluminium
phosphate or aluminium hydroxide - — = any untoward medical occurrence which follows immunisation and which does not
necessarily have a causal relationship with the usage of
the vaccine
antigen
antibody
adjacent
adverse reaction
principles of immunisation:
* Immunisation – the process of
inducing or providing – to
an — disease — (without — infection)
* Successful immunisation is
usually indicated by the
presence of —
* Response to vaccination can
vary
* The artificial induction or
provision of immunity may be
either — or –
immunity
infectious
artificially
natural
antobodies
passive or active
passive immunisation:
* Pre-formed — transferred to another individual
* Gives some — protection
– May not always — infection
* Provides only —-term immunity
* For people who have been – to a specific pathogen
– E.g. post-exposure prophylaxis (PEP)
– HCWs, pregnant women, international travellers
* Typically used by — patients who are unable to produce an effective immune response with active
immunisation
* Not routinely recommended for — adults capable of producing a durable response via active immunisation
examples:
1- — transfer:
the most important source
of antibodies in infancy
2- Heterologous hyperimmune serum
e.g. – Antitoxin (Equine)
3-Monoclonal antibody
produced by recombinant
DNA technology
In mouse myeloma host cells,
e.g. RSV
4-Intravenous —
* Normal
– From unselected / nonspecific donors (~1000 donors)
– Ex. HepA, Rubella, Measles
* Homologous hyperimmune globulin
– From selected / specific donors with high antibody titres
– Ex. HepB, VZV
antibody
immediate
prevent
short
exposed
immuocmpromised
healthy
transplacental
botulism
iv immunoglobin
active immunisation:
* Administration of an — substance(s) (vaccine) in order to stimulate – production of an immune response
* Protection is produced by the person’s own – system
and is usually— -lasting / –
– – factors play a large role in response
– Some may require a — for the effect to be long-lived
* Immunity and immunologic — are produced similar to the natural infection, but without the risk of disease
* Active immunisation my be by – attenuated or –
vaccine
antigenic
host
long lasting
permanent
host factors
booster
memory
live or non live
the goal of active immunity:
* The goal is to stimulate the host to produce a — immune response
– Usually by inducing – proliferation, — response, & – sensitisation
* If re-exposed to the pathogen, results in a — response
– Increased proliferation of— and formation of —
– Protects the individual from developing disease, ideally for life
primary
b
antibody
t
secondary
b and antibodies
Viral:
Measles
Mumps (Jeryl Lynn vaccine)
Rubella
Varicella (primary & zoster)
Yellow fever
Oral polio (OPV)
Rotavirus
Live attenuated influenza
Bacterial:
Smallpox
BCG
Oral typhoid
are all under: —-
Whole inactivated:
* Whole-cell pertussis (wP)
* Inactivated Polio (IPV)
Nucleic acid based
* Viral vector and mRNA
* SARS-CoV-2
Fractional/Subunit (purified antigen)
Protein/ Polysaccharide based:
* Acellular pertussis (aP)
* Haemophilus influenzae type B (Hib)
* Pneumococcal (PCV-7, PCV-10, PCV-13)
* Hepatitis B (HepB)
Toxoid (inactivated toxin):
* Tetanus toxoid (TT)
* Diptheria toxoid
are all under —
live atteunated
non live
live vaccines:
* Attenuated ( — ) agent
* – of response – gradual rise to a peak then decline
* Variable but “—” duration of immunity
– Immune response produced is similar to that of – infection and
includes both – and— components
* There will be a — effect with subsequent exposure
– Examples:
* Single dose – BCG
* Two doses – Rubella, Measles
– Typically done if immunity is likely to wane & long-term protection ( –
immunity) is required
* Three doses – Polio (3 serotypes of poliovirus)
* There is a possibility of generalised / severe infection in an immunocompromised individual
* Immune responses can be variable
weaker
amplification
long
natural
humoral and cellular
booster
herd immunity
non live:
* Cannot — and do not cause the – they are trying to prevent
* General rule: the more – a vaccine is to the disease causing form of the organism, the better the
immune response is to the vaccine
* Types of Non-Live vaccines:
– Whole inactivated
– Toxoid (inactivated toxin)
– Fractional/subunit
* Protein-based
* Polysaccharide-based
– Nucleic acid based
replicate
disease
similar
1- whole inactivated vaccines:
* Whole pathogen – (by heat or formalin) and — to induce an antibody response
* General rules:
– Not as effective as – vaccines
– Require 3-5 doses
* The immune response produced is mostly – (antibody)
* Antibody titre – over time
* Examples:
– Inactivated – vaccine
– – vaccine
2- toxoid vaccines:
* Modified – toxin that has been rendered non- toxic but still remains –
* Has the ability to stimulate the formation of antibody to the —
– i.e. creates — to the toxin that causes disease NOT the bacteria
* Examples:
– —
– –
2- fractional / subunit :
- protein based:
* Contains only — — proteins of
an infectious agent
* Example:
– Acellular pertussis
* Pertussis toxoid +
proteins from the bacterial surface
- polyscacirde based:
* Contains polysaccharide
from bacteria —
* Not —
immunogenic if <2yoa
* No – response
* Produce antibodies with –
functional activity than that
produced by the infection
* Example:
– Adult pneumococcal vaccine
killed
injection
live
humoral
falls
polio
hepatitis a
bacterial toxins
antigenic
toxins
immunity
diphtheria and tetanus
specific antigenic proteins
surface capsule
concisely
booster
less
fractional vaccines:
Fractional vaccines:
Conjugate polysaccharide vaccines
* Polysaccharide — linked to a protein
– Induces a more – immune response
* Increased immunogenicity in –
* Antibody booster response to multiple doses of vaccine
* Examples:
– Hib vaccine: polysaccharide joined to tetanus toxoid
– MenC vaccine: polysaccharide joined to tetanus toxoid
– PCV (children’s pneumococcal vaccine): polysaccharides from the
surfaces of 13 types of pneumococcal bacteria are linked to diphtheria toxoid
– MenACWY: polysaccharides from the surfaces of 4 types of the
meningococcal bacteria joined to diphtheria or tetanus toxoid
nucleic acid based vaccine:
* – vaccines
* Instrumental in —
– – vaccine
– Viral – vaccine
chemically
potent
infant
novel
covid 19
mRNA
vector
adult immunisation:
Females:
* Child-bearing age and
seronegative for
rubella
– —
* Pregnant women
(varies by country):
– Influenza, pertussis
(TdaP) recommended
in Ireland
– — toxoid x 2 in
some countries
Immunocompromised:
* Individuals in specific high
risk groups
– HBV, influenza,
pneumococcal, typhoid
Immunocompetent:
* Previously non-immunised
individuals
– —
* Travelling abroad
– Country dependent
– May include HepA, typhoid,
MenACWY
MMR
tetanus
tetanus
adult immunisation:
Health Care Workers:
* Hepatitis B
* Hepatitis A
* BCG
– No licensed vaccine available
at present in Ireland
* Influenza
– —-line staff
– Those involved in long-term
care of the —
* Pertussis (TdaP)
– Those caring for – , — women, & –
* In some clinical
circumstances need to
check:
– — immunity
– — antibody
– – antibody
* Polio booster to some
– E.g. Lab staff working with — samples, performing
faecal cultures
front
elderly
infant preggo n immunocmpromsied
Marcella
rubella
measles
feacals
immunisation:
Precautions / When to delay vaccines:
* Acute severe febrile illness
– — until recovery
* Recent intravenous immunoglobulin (IVIG)
– May impair the efficacy of – & – live attenuated vaccines
* Topical immunomodulators, e.g. –
* Previous type – hypersensitivity reaction
– Severe swelling & erythema involving most of the
diameter of the upper arm after vaccination
– Can occur in adults following tetanus or diphtheria toxin-
containing vaccines
defer
MMR n vaccella
tacrolimus
3
immunisation contradiction:
* True contraindications are rare!
* Applies to a – or — of a vaccine
* All vaccines:
– — to the vaccine or vaccine components
* Live vaccines:
– — – theoretical risk to the fetus
– Some – conditions
– — : don’t give after 8 months (risk of intussusception)
Conditions that are NOT contraindications to
vaccination:
* – infection with – < 380C
* —
* Family or personal history of convulsions
* Short term — treatment or long-term
therapy with less than 20mg/day (0.5mg/kg/day)
* – allergy – MMR is safe in egg allergy
* Asthma / eczema / hayfever
dose n further fose
anaphylaxis
preggo
immunocompromised
retrovirus
minor
fever
prematurity
contristeriods
food
vaccination:
Pregnancy:
* Avoid – vaccines because of
theoretical harm to foetus
– However, if significant risk of
exposure to poliomyelitis, need for
immunisation outweighs risk
* Some inactivated vaccines are/may
be given
– Ex. Tetanus toxoid
* – doses for 1st pregnancy, – dose for
each subsequent one (Malaysia)
– Inactivated influenza vaccine
* Many countries, every pregnancy
* Pertussis (TdaP) immunisation is
now recommended in several
countries, including Ireland
– 16 weeks, in every pregnancy
HIV:
* Should receive all routine
vaccinations (+ some additional
ones) with the exception of —
– Timing depends on type of vaccine and level of immune suppression
– Live vaccines should be delayed until patient receiving anti-retrovirals (ARVs) and the CD4 count has returned to normal levels
* Oral – vaccine not
recommended because of an
increased risk of paralytic
poliomyelitis with OPV in
immunocompromised pts
live
2
1
BCG
polio
side effects of vaccination:
- Adverse events following immunisation may be:
– Programme-related, e.g. due to wrong dose, incorrect storage,
expired vaccine
– Vaccine-induced, e.g. fever, rash, anaphylaxis
– Coincidental
– Unknown - Categorised as:
– Adverse event following immunisation (AEFI)
– Adverse vaccine reaction (AVR) - The rate of AVRs is much lower than the rate of morbidity
resulting from disease in unvaccinated individuals - Harmful effects on immunodeficient hosts, e.g.
disseminated BCG effect in HIV-infected individuals - In Ireland, all suspected adverse events are / should be
reported to the Health Products Regulatory Authority
(HPRA)
small box:
* – virus
* — mortality rate, ~30%
* Symptoms: fever and a pustular
rash which would result in
severe—-
* WHO Intensive Eradication
Programme (1967)
* Last natural case was in
Somalia in 1977
– Intensive tracing & vaccination
campaign led to 54,777 people being
vaccinated in the next two weeks
* 2 years of surveillance
* Eradication announcement in
1980
- vaccine:
hepatitis b immunisation :
* Recombinant protein — vaccine (—immunisation):
– First recombinant vaccine
* HepB surface antigen (HBsAg) inserted into — cells
* Produces only non-infectious surface protein
– Vaccine also contains an –
* Schedule:
– – doses (0, 1, 6 months)
– Blood test for titre 2 months after last dose (aim >10 mlU/ml)
* Post-exposure prophylaxis (—immunisation)
– Vaccine +/- specific intravenous immunoglobulin (Hepatitis B IG or
HBIG)
* Babies born to mothers who are HBV+
* Household exposure
* Sexual exposure
* HCWs and those accidentally exposed to body fluids or blood
* Injuries from discarded needles in the community
variola
high
scarring
live
active
subunit
yeast
adjuvant
3
passive
Hepatitis B is a potentially life-threatening — infection caused by the hepatitis B virus (HBV)
Morbidity:
* Up to 90% of — infected infants may become—-
* Between 2-20% of infected
adults become chronic
carriers
* Carriers may develop:
– Chronic hepatitis
– Cirrhosis
– Hepatocellular carcinoma
Mortality:
* Approximately 1% of those
hospitalised with acute HBV
infection die
* Superinfection with delta
agent [Hepatitis D] may
lead to fulminant liver
failure
meningococcal disease:
* Neisseria meningitidis
* Mortality & Morbidity
– Approaches 100% in untreated meningococcal meningitis
* 10-15% if treated
* Long-term— complications
– — infection (BSI) also very high mortality
* Limb loss, multi-organ failure (MOF), Waterhouse-Friderichsen syndrome
* Included as part of routine schedule in some countries and
defined populations
– Polysaccharide meningococcal vaccines are no longer recommended
– MenACWY conjugate vaccine
* Travel to high risk areas with epidemics or hyperendemic disease
– Meningococcal B vaccine (4C MenB) – multi-component protein
vaccine
– MenC conjugate vaccines (MenC, Hib/MenC)
Saudia Arabia: pilgrims - Hajj
* Very large outbreaks of
disease in pilgrims in the
1980s & 1990s
* Certification of vaccination
required by authorities since
1988
– Visa entry requirement since
2000
* Current general
recommendation: quadrivalent
ACW135Y
Ireland:
* MenC conjugate vaccine
introduced in Oct 2000
* MenB vaccine introduced in
Dec 2016
liver
vertically
chronic carrier
neurological
Bloodstream
influenza virus:
* — respiratory illness due to
influenza A, B, or C
* Seasonal outbreak &
epidemics worldwide, &
unpredictable pandemics
– Ex. 1918 pandemic (‘Spanish flu’)
Morbidity & Mortality
* Usually — infection
(uncomplicated influenza)
* Associated with increased
M&M in certain high risk
populations (complicated
influenza)
Types of vaccines:
* –
– Yearly, in advance of flu season
(Sept/Oct)
* Due to mutation rates
– Contains – & 3-4
influenza serotypes
* Ex. 2 serotype A + 1-2 serotype
B (tri or quadrivalent)
* — attenuated (LAIV)
– Available in N America, UK
(children) & Ireland since 20
acute respiratory
self limiting
non live
proteins
live
influenza vacciation recommediation :
1. Any individual >6moa at
increased risk of influenza or its
complications
- — illness requiring regular
medical follow-up
- — due to
disease or treatment
- All persons aged 65+
- All pregnant women (any
gestation) & up to 6wks
postpartum
- Morbid obesity
- Children & adults on long-term
aspirin therapy
- Residents of nursing homes and
other long-term care facilities
- Pig / poultry / waterfowl workers
2. Those at increased risk of
transmitting influenza to a
person at high risk for
complications
- Healthcare workers (HCW)
- May be considered for family,
carers, and household
contacts of patients at
increased risk
3. All children between 2-17
yoa for live intranasal
vaccine
chronic
immunsipression
- Healthcare workers, usually healthy adults, are likely to have —
responses to vaccination, unlike
some patients - Hospitalised patients can acquire
influenza from infected HCWs,
visitors, or other patients - About 30% of people infected with
influenza are — but can still be infectious to others - Influenza can – a vulnerable
patient - Vaccination is one of the greatest public health achievements in
human history - Vaccines:
– Are safe and effective when used correctly
– Protect the entire population, not just the individuals receiving the inoculation
– Are not risk-free, and adverse events will occasionally occur following vaccination - Public trust in vaccination is key to the success of immunisation
programmes
excellent
asymptomatic
kill
