Vaccines Flashcards
What is Variolation and where was this process practiced
scarification of unimmunized individuals with a tiny amount of material from diseased patients with smallpox
practiced in China and the Middle East
2-3 % were not protected and died
variola is latin for pox
What was practiced in China and the Middle East that used scarification and a tiny amount of material from a diseased person
variolation
How was the first vaccination made
a pustule from an infected individual (milkmaid) with cowpox was scratched against the skin
this conferred some cross protection to subsequent exposure to small pox
1% were not protected fully and lesions that did develop were not as severe
What bacterial vaccines are out there
Diphtheria
Pertussis
Tetanus
What viral vaccines are out there
smallpox
poliomyelitits
measles
mumps
rubella
What are seven key aspects that makes an ideal vaccine
must be safe with minimal adverse side effects
must be efficacious: elicit a strong and long lasting response
delivered in combination with other vaccine components, so have to get fewer shots
must be heat stable, dry stable and have a long shelf life
low cost and easy to manufacture and administer
minimal maintenance programs, so fewer boosters
if its against a mucosal pathogen, it must be administer orally or intranasally to elicit a mucosal immune response
What five aspects make a good ANTIGEN
where the pathogen occurs: mucosal sites, systemic, etc
what the major virulence factors are: toxins, capsules, adhesins(non yet but in process)
how many antigenic variation exists, number of serotypes
if the antigen mimics host antigens: potential for non-response or autoimmunity
if the pathogen is extracellular or intracellular: humored vs cell mediated immunity
What is herd immunity
collective immunity through mass immunization confers indirect protection on the nonimmune members
important force in preventing epidemics
not only confers protection to the individual receiving the vaccine, but it also protects public health
Who cannot be vaccinated and how can they be protected
if they have a major allergy to the vaccine components
immunocompromised
age
transplant recipients
everyone else that can must be vaccinated to get herd immunity for the people unable to be vaccinated
What are five main barriers to vaccine success
- there are a lot of childhood vaccines and the child must come in often, doesn’t always happen so the solution is to try and combine vaccinations into one shot
- similar threshold to safety criteria as seen for antibiotics, elevated concern that most vaccines are targeted to children: thereat of lawsuits that has disengaged some companies from investing in vaccine development
- vaccine successes are their own downfall: elimination of diseases makes people forget the impact that vaccines have
- technical barriers: some pathogens have outsmarted us
- anti-vaxers refusing to vaccinate, this has been going on for centuries and has been seen historically
What are the different types of vaccines
live attenuated
inactivated
subunit vaccines
toxin vaccines
conjugate vaccines
recombinant vector vaccines
What is in the DPT vaccine
Diphtheria: toxoid
Tetanus: toxoid
Pertussis: whole killed cells
What is the side effects of pertussis vaccination
moderate side effects in 20% of cases
included discomfort and convulsions
very rarely: can lead to hearing loss or brain damage
What is in the DTaP Vaccine
in 1990s
Diphtheria: toxoid
Tetanus: toxoid
Pertussis: acellular proteins
pertussis toxoid
outermsmbrane proteins: pertactin and FHA
fimbriae proteins types 2 and 3
What is a conjugate vaccine and what is an example
polysaccharides
HiB vaccine
Pneumococcal
Meningococcal
example would be a polysaccharide connected to a protein - the B cell recognizes the polyprotein molecule but not the protein part – so it shows the T cell the protein part — then memory B cells are produced that recognize the polysaccharide – so then the B cells respond to the polysaccharide antigen on bacterial surface
What is characteristic of the Haemophilus influenzae bacteria
gram -
rod shaped
non motile
20,000 cases a year in the early 1980s, mostly in children under 5 years old.
Epiglottitis, pneumonia,meningitis.
PRP Capsule prevents C3b from binding/phagocytosis.
Vaccine: conjugated vaccine consisting of a
polysaccharide bound to a protein (carrier protein)
What is characteristic of the Haemophilus influenzae disease
20,000 cases a year in the early 1980s mostly in children under 5 years old
epiglottitis, pneumonia, meningitis
PRP capsule prevents C3b from binding/phagocytosisi
vaccine: conjugated vaccine consisting of a polysaccharide bound to a protein- a carrier protein
What type of vaccine is available for Haemophilus influenzae
vaccine: conjugated vaccine consisting of a polysaccharide bound to a protein- a carrier protein
prevalence of HiB decreased from 23 per 100,000 cases in 1991 to .9 cases per 100,000 in 1996
What are the types of pneumococcal conjugate vaccines
Prevnar 7: covers 7 serotypes- 80% of disease - 2000
Synflorix: covers 10 serotypes- 2009
prevnar 13: covers 13 common serotypes - 2010
Why do vaccines not work
elicit the wrong immune response
side effects, such as an allergic response to vaccine components or intestinal blockage such as in rotavirus
worsens disease
Why do vaccines not work against TB
elicits the wrong immune response
Why do vaccines not work against Salmonella
elicits the wrong immune response
Why do vaccines not work against Cholera
elicits the wrong immune response
Why do vaccines not work against Rotavirus
side effects, causes intestinal blockage
Why do vaccines not work against Chlamydia
worsens the disease
Why do vaccines not work against RSV
worsens the disease
