Lecture #15 Flashcards
What can/cannot be used to control/cure a viral infection?
Cannot use antibiotics
Can use vaccines
What are vaccines made of?
Either:
- A suspension of a whole organism
- Portions of organisms (antigens)
What do vaccines do?
Stimulate an immune response without causing a disease (produces memory cells to a specific antigen)
Why are vaccines needed?
To control the spread of communicable diseases by behavioural/environmental methods
What is cholera and how can it be controlled?
Bacteria disease in small intestine that causes vomiting and diarrhea
By proper sanitation
When easy methods (sanitation and use of condoms) fail to prevent communicable diseases, what is used to rid them?
Bacterial diseases are treated with antibiotics
Viral diseases generally cannot be cured
What is the best way to control diseases when there is no cure?
Vaccines
What are the 6 different types of vaccines?
- Attenuated Whole Agent Vaccines
- Inactive Whole Agent Vaccines
- Toxoids
- Subunit Vaccine
- Conjugated Vaccines
What is a weakened living microbe?
A microbe that has had an mutation introduced
Ex. A virus can absorb, penetrate and uncut but not reproduce
How do Attenuated Whole Agent vaccines work?
They used weakened living microbes that closely mimic the actual virus so that it stimulates both Cell and antibody mediated responses
Which type of vaccine can often provide life long immunity (no booster shot required)? What are examples of specific vaccines?
Attenuated Whole Agent Vaccines
Ex. MMRV vaccine (Measles, Mumps, Rubella, Varicella)
What is a risk factor of Attenuated Whole Agent Vaccines? Who is most at risk?
The virus/bacterium can revert back to original pathogenic form.
Immunocompromised or pregnant women are most at risk
What are Inactive Whole Agent Vaccines made of?
Whole agents that have been killed
What are examples of Inactive Whole Agent Vaccines for bacteria and viruses?
Viruses- Rabies, influenza, polio
Bacteria- Vibrio cholera
What are toxoids and what are they made from?
Inactivated proteins (dummy particles, look the same but doesn't have what it takes to be a virus) Made from purified proteins
What do toxoids do to give immunity?
Causes the immune response to act against the toxoid. Stimulates the antibody mediated (B cell) response only.
Do toxoids give long lasting immunity?
Not as long as others and required multiple injections for full immunity
What is an example of a toxoid vaccine? How often is a booster shot required?
DTaP vaccine (diphtheria, tetanus and pertussis) Required shot every 10 years
What in a subunit vaccine made up of?
Purified components from viruses or bacteria
Subunit vaccine stimulates what to give us immunity?
Antibody mediated response only
What is taken from streptococcus pneumoniae to be used for a subunit vaccine?
Purified capsule polysaccharide
What does a pneumoshot protect against and what is it made up of?
Protects against pneumonia
Made up of purified capsule polysaccharide founding streptococcus pneumoniae
What category of vaccines make “extremely safe vaccines”? Why are they extremely safe?
Subunit vaccines
Safe because the disease causing agent is not present
What makes up the hepatitis B vaccine?
Viral coat proteins produced by a genetically modified yeast
What are conjugated vaccines and why are they used?
A polysaccharide antigen combined with a protein antigen.
Used because children do not respond to capsular polysaccharides therefore using this results in a much stronger immune response
What is an example of a conjugated vaccine (what is it made of)? What is it used for?
Haemophilus influenza capsule combined with diphtheria toxoid.
Induce an immune response in children as young as 2 months
What are adjuvants? What do they do for a vaccine?
Chemical additive that increases the immune response
Allows for an improved response to vaccine
What is an example of a vaccine that uses adjuvants? What is the adjuvant made of?
H1N1 uses adjuvants made from shark cartilage
What is herd immunity?
People who have not been vaccinated still have a reduced chance of contracting the disease because they are surrounded by people who have already been vaccinated
What is usually the result of someone who lives in a herd immunity area? What is the problem with that?
Result: many parents choose not to have their children vaccinated
Problem: Most parents who choose that have not actually ever had measles or polio meaning their children would not have immunity and could contract it easier
How many people have mild symptoms of polio? How many have extreme (result in paralytic poliomyelitis?
99% mild
1% paralytic poliomyelitis
What does paralytic poliomyelitis cause?
The extremities to be permanently crippled and respiratory muscles can be paralyzed causing death
What type of infection is measles?
A respiratory infection
What are can measles cause early on and later on?
Early: characteristic rash
Later: Permanent brain damage (subacute sclerosing panencephalitis- causes inflammation in brain)