Vaccines Flashcards
What is concept of vaccinology?
When first exposed to pathogen, there are no specific IgG antibodes against pathogen.
Infection can progress to disease.
Body will gerenate antigen specific IgG antibodies and mount a memory immune response.
In the next exposure, memory immune response provides protection from disease.
If exposed to pathogen that did not lead to disease, immune response would simply be generation of immune memory.
Use antigenic but non-pathogenic structures.
What are the types of vaccines?
Live -attenuated vaccines - MMR
Pathogens were evolved to replicate in different conditions to human infection so fail to replicate in humans..
Inactivated - pathogen treated with chemical/heat so unable to replicate + cause disease.
= Influenza.
Toxoid - treating toxin so doesn’t cause disease = Tetanus.
Info about influenza vaccine
Inactivated vaccine.
Trivalent.
Virus grown in culture and inactivated with formalin.
Virus now inactivated, so cannot replicate and doesn’t cause disease, even in immunocompromised individuals.
First doses primes immune system, as opposed to protective immunity.
Usually develops after 2nd/3rd dose.
Safer + more stable.
BUT can trigger hypersensitivity - due to egg inoculation contaminants…
What is the standard influenza vaccine?
Intramuscular, trivalent, inactivated vaccine.
Vaccines to generate IgG1 for 3 different strains…
Contains 2 influenza A serotypes, and 1 influenza B serotype.
How are vaccines produced?
Egg propagation.
Innoculation of egg in order to accumulate virus - propagate high pathogenic avian influenza strains…
Each strain prediction must be evolved from old strains.
When does production begin?
Need to decide strain for seasonal influenza almost a year in advance, based off currently circulating strains.
2 Influenza A and 1 influenza B serotype.
Production takes 10 months.
Begin innoculations in october to provide time for generating immune memory in at risk patients prior to december-march peaks.
