The Immune System Part 3 Flashcards
Herd Immunity is:
a type of immunity that occurs when the vaccination of a portion of the population provides protection to the unprotected individuals of that population
- protection is provided to all individuals in the population due to the inability of the pathogen to spread
What are the four strategies of vaccines for artificial?
Attenuated organisms
killed/subunit organisms
small fragements
toxins
Attenuation is:
process by which virulence is reduced so that although the organism is still active; it is no longer causing disease - live with an ability to replicate in host cells
- a LIVE vaccine **
True or false: in a attenuated vaccine the virus must be dead to replicate properly
FALSE! the virus must stay alive to be able to replicate the vaccine cells
What is critical in regards to storage of an attenuated vaccine?
temperature can reduce or increase replication of virus therefore leading to a pathogen causing disease
- polio vaccine must be monitored to ensure it wasnt exposed to high temperatures.
In regards to maternal antibodies, when should a baby receive their MMR?
12 months old - because this is when the maternal antibodies decrease
-when the baby is born, maternal antibodies are given to the lil bebe that will provide protection from live attenuated vaccines - so they will likely be killed = be sure that the maternal antibodies are gone
Where is their a risk for back mutation?
in polio ! - chance t
What are the risks in attenuated vaccines?
risk for immunocompromised people
the immune system must be under control when given
they can be hazardous because the modified micrboes ma retain enough residual virulence to cause disease
-pregnant women shouldn’t take this
Examples of attenuated vaccines are”
MMR, polio, flu shot, varciella roster, rabies vaccines
How was the rabbies vaccines acheived?
serial infections in rabbits led to a live virus strain that was more virulent in rabbits then it was in dogs.
Process of attenuation
pathogenic virus is isolated in patient –> put in animal cell –> viruses acquire a mutation that allows it to grow in animal cell, then the virulent cell does not have the ability to grow in a human cell :)
Killed and subcellular vaccines are:
virons inactivated by chemical procedure; the infectivity and viral ability to replicate are eliminated but antigenicity is not compromised - killed for the use in vaccines and its important antigen remain similar to that of the living organism as possible
Killed vaccine are antigenically weak, what does this mean?
its administered at high doses or incooperated with materials called adjuvants (help increase the vaccine)
What is a positive about killed vaccines?
there is no chance it can replicate, revert, mutate or retain an residual virulence = safer
what is a negative about killed vaccines?
you have to administer a shit ton of boosters to keep the immunity up
Examples of killed vaccines?
polio, influenza, hep a, modern day rabies
What are two toxoids?
1) Diphtheria: toxin is encoded by bacteriophage
2) Tetanus
What is a toxoid??
a inactivated toxin
What is the process of bacterial exotoxins?
modification of a toxin to a toxoid - by chemical modification
Small fragements: happens when some cells in the body pick it up and acquire immunity to it: true or false?
true betches
Give 2 examples of a fragment vaccine
Hep B: 1st generation extracted from blood plasma (hboAG) from hepb patients, now its cloned by yeast
HPV: protects from cervical cancer; vaccines has legnthened the average life expectancy
Passive Immunity: Natural VS Artificial
Natural: placental tranfer of IgG, and breast feading (Transfer of IgA, mucosal)
Artificial: antibodies from other individuals and from immune animals
What are the advantages and disadvantages of passive immunization?
Adv: immediate protection
DIS: no long term protection, risk of infection with unknown pathogens, serum sickness
What is the product and use of Diphtheria
P: specific Ig from horse
U: tx of diphtheria
