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Vaccines
Rationale
Successes
Problems
Nester 5th edition Chapter 17th
Nester Chapter 17
• Principles of Immunization
• Naturally acquired passive immunity
• Naturally acquired active immunity
• Artificially acquired passive immunity
• Artificially acquired active immunity
Principles of Immunization
• Antiserum
– Serum containing antibodies
• Antitoxin
– Serum protects against toxin
• Immune globulin
– Passive immunization preparations contain
gamma globulins IgG.
• Hyperimmune Globulins
– Sra of donors with high amount of antibodies
Nester Chapter 17
• Herd Immunity - the inability of an infectious
disease to spread in a population because of
the lack of a critical concentration of
susceptible non-immune hosts.
• Vaccine - a preparation of attenuated or
inactivated microorganisms or viruses or
their components used to induce active
specific immunity.
Herd Immunity Figure 2
Infectious
Agent
Active
Immunization
or Recovery
from Natural
Disease
Non-Immune
Disease
Non-Immune
No disease
Vaccines
• Attenuated vaccine agents
– Either organisms or viruses that cause a
sub-clinical or mild disease and that
produce long lasting immunity.
– Antigen is intact, may decrease circulation
of wild type
– Examples- mumps, measles, rubella,
yellow fever and Sabin polio
Nester Chapter 17
• Inactivated vaccine agents
– Antigen is altered slightly to still produce
immunity without the disease
– Whole agents
• Killed micro-organism or inactivated virus
• Example- cholera, influenza, rabies and Salk
vaccine
– Toxoid
• Inactivated toxins
• Example- Diphtheria and tetanus
Inactivated vs. Attenuated Virus Vaccines Table 1
Property
Attenuated
Inactivated
Route of Administration
Injection, oral, or nasal
Injection
Dose of Virus
Low
High
Number of Doses
Single
Multiple
Duration of Immunity
Long-term
Short-term
Antibody Immune Response
IgG and IgA
IgG
Cell-mediated Immune Response
Good
Poor
Heat Lability in Tropics
Yes
No
Reversion to Virulence
Rarely, OPV
No
Cost
Low
High
Nester Chapter 17
• Protein sub-unit vaccines
– Key protein antigens or antigenic
fragments
– Examples- acellular pertussis (aP)
• Recombinant vaccines
– Subunit vaccine produced by genetically
engineered micoorganism
– Example- Hepatitis B
Nester Chapter 17
• Polysaccharide vaccines
– composed of the polysaccharide that make
up capsule
– elicit a poor response
• Conjugate vaccine
– improvement over purified
– Haemophilus influenza type b and
Streptococcus pneumonia
Nester Chapter 17
• Adjuvant
– Inactivated contain a substance that
enhances the immune response to antigens
– Currently approved in United States is
alum (Aluminum hydroxide and
aluminum phosphate)
Comparison of the Antibody Response to Inactivated and
Attenuated Vaccines – Figure 1
Serum IgM - Both
Serum IgG - Both
Nasal IgA m- Atten
Anti
bod
y
Serum IgA - Both
Lev
els
Duodenal – IgA - Atten
Time in Days
Nasal & Duodenal IgA Inactivated
Nester Chapter 17
• Text 17.1 Some important vaccines
• Text 17.3 Effectiveness of vaccines in US
(20th Century)
• Text 17.4 Recommended schedule in the
US (2000)
• Text 17.5 Diseases for which new
vaccines are sought
Vaccines
• Rationale
– To produce, without harm to the recipient,
a degree of resistance sufficient to prevent
a clinical attack of the natural infection
• Goals
– To increase Herd Immunity
– To help limit a present epidemic
– To prevent a future epidemic
Pertussis Death Rate/Million Citizens by Century –
Figure 3
Identification
Vaccine
Penicillin
Vaccines
• Properties of an Ideal Vaccine
–
–
–
–
–
–
Promotes effective immunity
Confers lifelong protection
Has no side effects
Is stable
Is affordable in price not quality
Is seen to be good and effective
• No vaccine is perfect; some are close.
Prevention
• Phases of vaccine testing
– Phase I
• testing for safety
• ability to induce an immune response
– Phase II
• determine optimum dose
• kinds and duration of responses
– Phase III
• effectiveness
Vaccines
• Duration of immunity varies:
– For different vaccines.
– For different groups of people.
– Since protection does not always relates to
antibody level.
Vaccines
• Contraindications - Do not give:
– Vaccines to someone with an acute disease
or neurological disturbance.
– Attenuated vaccines to pregnant women.
– Vaccines in the first trimester of pregnancy.
– Vaccines to people on immunosuppressive
drugs or irradiation or with AIDS.
– Vaccines made in eggs to people allergic to
eggs.
Vaccines
• Hazards
–
–
–
–
–
–
Mild to moderate pain at the injection site
Fever and malaise for a day or two
Anaphylaxis - rare
Encephalopathy
Guillain-Barre syndrome
Epilepsy
Vaccines
• Hazards
–
–
–
–
–
–
Death from the vaccine viral strain
Aseptic meningitis
Demyelinating disease
Deafness
Sterility
Arthritis
Vaccines
• Safety considerations
–
–
–
–
–
Use a separate sterile syringe and needle
Avoid errors - check the vial
Consider patient’s history
Consider contraindications
Keep careful records
Virus Vaccine Types
• MMR – measles, mumps, rubella
• Polio
• Chickenpox
• Hepatitis A
• Hepatitis B
Measles
• Disease - Fig. 22.21
– 0-1000 cases/year U.S.
– Death 1-2/1000 up to
150/1000 (15%)
– Secondary infections
85%
– Encephalitis 1/2000
1/2 die; 1/2 lose a
function
– Pneumonia 1/20 (5%)
• Vaccine
– Encephalitis or
severe allergic
reaction 1/1,000,000
– Thrombocytopenia
purpura 3/100,000
– Aseptic meningitis
1/11,000 (mumps)
– Death is rare
Mumps
• Disease
– 0-2 cases per 100,000 in
US
– Hearing loss or deafness
– Encephalitis
– Pancreatitis
– Aseptic meningitis 10%
– ¼ cases in post-pubertal
males orchitis
– 1 in 20 post-pubertal
females ovarian
involvement pelvic pain
• Vaccine
– Aseptic meningitis 2%
Rubella
• Disease
– 0.1-0.2 cases per
100,000 in US
– Congenital rubella
• Blind
• Deaf
• Retarded
• Heart defects
• Vaccine
– Arthralgia
– Transient arthritis 23 weeks
– Knee joint arthritis
may last 24 months
– Same as MMR
Polio
• Disease
– 0 cases since 2000
from vaccine in US
– Cases come from
outside US
– Paralytic death rate
1-2 %
• Vaccine
– 8 cases/yr
– 1 case/2,500,000
doses
– Guillain-Barre
Chickenpox
• Disease
– 10-60,000 cases per
year in US
– 50-90 deaths
– Zoster 77/100,000
– Encephalitis
– Pneumonia
• Vaccine
– Zoster 18/100,000
Hepatitis A
• Disease
– 3-10 cases per
100,000 in US
– Long convalescence
period of about a
month
– 11% hospitalized
• Vaccine
– Mild or of no
consequence
– Same as placebo
– Soreness and redness
at inoculation site
Hepatitis B
• Disease
– 3-25 cases per
100,000 in US
– Death 0.5-2%
– Cirrhosis 4,000/yr.
• 25% die
– Cancer 800/yr.
– 2-10% adult carriers
– Infants 90% become
carriers
• Vaccine
– Autoimmune disease
• Lupus
• Rheumatoid arthritis
Bacterial Vaccine Types
• DPT
– Diphtheria
– Pertussis
– Tetanus
• H. influenzae
• Pneumococcal pneumonia
Diphtheria
• Disease
–
–
–
–
–
0-5 cases a year in US
Death 1/20
Heart
Kidney
Nervous system
• Vaccine
– toxoid
– Continuous crying
then full recovery
1/100
– Guillain-Barre
– Brachial neuritis
– Anaphylaxis
Pertussis
• Disease
– 0.5-3.5 cases per
100,000 in US
– Death 1/200
– Encephalitis 1/20
– Pneumonia 1/8
• Vaccine
– Acute
encephalopathy 0-10
cases/1,000,000
immunizations
– Acellular vaccine has
far fewer side effects
especially of the
neurological types
Tetanus
• Disease
– 30-50 cases /yr. in
US (97% nonvaccinated)
– Mortality 30% in US
– Mortality 50% or
more worldwide
• Vaccine
– toxoid
– Convulsions then
full recovery 1/1750
– Guillain-Barre
– Brachial neuritis
– Anaphylaxis
H. influenzae
• Disease
– Age > 5: 0.5/100,000
– Age < 5: 2/100,000
– Death 3-7%
neurological disease
– Pneumonia - death
50%
– Epiglottitis
– Septic arthritis
• Vaccine
– Reduced meningitis
so much that S.
pneumo has
replaced H.
influenzae
– Juvenile diabetes is a
side effect
Pneumococcal pneumonia
• Disease
– Death 5-20%
untreated
– Resistance is a
problem
• 1 state: >401 cases
• 10: 101-400
• 15 + 1: 1-100
• 0: rest
• Vaccine
Health People 2010