Vaccines Flashcards
What is the difference between Innate & Adaptive immunity?`
Innate Immunity: - Basic resistance to disease (immunity) - Provides immediate protection - Same response regardless - No memory (Eg. Phy barriers (Skin/mucosa), Physiologic factors (Gastric acid), Process (Inflmm), Cells of immune system)
Adaptive Immunity:
- Protection develops more slowly (days)
- Developed after exposure to antigen
- Effective only against specific antigen
- Has memory (enhanced ability to deal with recurring antigen)
- -> Upon 1st exposure, developement of pri immune response with proliferation of activated B cells & T cells into effector cells, and some to memory B & T cells
LO1: How do vaccines elicit an immune response & provide protection?
- Prime the adaptive immune system to provide a long-lasting targeted response that prevents infection
- By memory from the Adaptive Immunity (Basis of vaccination)
- -> Activation of memory cells –> Secondary response with shorter lag time between exposure & production of response + Heightened state of activity
- -> Faster & stronger immune response
What does it mean by ‘Vaccination is a form of active immunization’
Provide immunization before host even comes into contact with the pathogen
LO2: Characteristics & distinctions of LIVE VACCINES
What: Weakened virus, often by repeatedly passing through tissue culture in which it replicates poorly
- > Immunogenic: Activates killer T Cells
- 1/2 doses can provide lifelong immunity
- Temp-sensitive: Must be refrigerated
- < safe for people with weakened immune system
- Need to be given spaced apart from other live vaccines
- Not generally given to infants
Eg: Measles, mumps, rubella, varicella, rotavirus
LO2: Characteristics & distinctions of INACTIVATED VACCINES (non-living)
What: Inactivated by treating with heat/chemicals to kill it
- Easy to store & transport
- Low risk of causing infection
- Elicits weaker immune response
- May require several doses/boosters to attain adequate response
Eg: Polio, Rabies, Hep A
LO2: Characteristics & distinctions of SUBUNIT VACCINES (non-living)
What: One/more parts of the pathogen are isolated & used to evoke an immune response
- Low risk of causing adverse reaction
- Can be used in people with weakened immune systems
- Can be difficult to manufacture
- May require boosters to attain adequate response
Eg: Hep B, Influenza, Pertussis Pneumococcus
LO2: Characteristics & distinctions of TOXOID VACCINES (non-living)
What: Toxin produced by pathogen is deactivated & used to produce the immune response
- Unable to cause disease/ spread
- Stable, easy to distribute
- May require boosters to maintain immunity
Eg: Diphtheria, tetanus
LO2: Characteristics & distinctions of RECOMBINANT VACCINES (non-living)
What: Produced using genetic engineering. May contain no actual virus/ modified strain of virus (as with live oral typhoid)
Eg: Hep B, HPV
Precautions with live vaccines
- Avoid in pregnancy/ severely immunocompromised
- -> Concern for uncontrolled replication -> Cause actual clinical infection
- Not usually given to infants
- Avoid giving another live vaccine within 28 days
- Space 3-10 mths apart from other ab-containing products
LO3: List vaccines available for infections transmitted by RESPIRATORY route
- Influenza
- Pneumococcus
- Meningcoccus
- H. influenzae
- BCG (Tuberculosis)
- MMR (Measles,Mumps,Rubella), Chickenpox
LO3: List vaccines available for infections transmitted by FOOD & WATER route
- Hep A
- Typhoid
- Cholera
- Rotavirus
LO3: List vaccines available for infections transmitted by VECTOR-BORNE route
- Yellow fever
- Jap Encephalitis Dengue
LO3: List vaccines available for infections transmitted by BLOOD & BODILY FLUIDS route
- Hep B
- HPV
LO3: List vaccines available for infections transmitted by CONTACT route
- Tetanus
- Rabies
- Shingles
LO4: Describe principles of Herd Immunity
High vaccination rate in population such that most community members are protected, even the unimmunized individuals