Question

Microbiology Tutorial: Introduction to Vaccine Technology

Answer 1

\({\bf{Basic~Terminology:}}\)
- vaccine: substance that stimulates immune response/antibody production for a disease without causing that disease
- herd immunity/herd effect: phenomenon in which a high proportion of individuals in a population are vaccinated, necessary to protect those who cannot be vaccinated. will not be as effective if the vaccinated population drops below a certain point, different for each disease
- active immunization: immunity in response to an infectious agent or a vaccine
- passive immunization: immunity as a result of injecting antibodies, used to prevent disease, ease symptoms, block toxins, and protect those who cannot be vaccinated

\({\bf{Inactivated~vs.~Live:}}\)
inactivated: vaccine with heat-killed pathogen
- immunity is temporary
- may only be humoral and not cell mediated (see tutorial on immunity)
- does not cause local immunoglobin A response
- requires larger doses + boosters

live: vaccine with live virus
- more effective but may be dangerous for immunocompromised individuals
- may become virulent
- may not stay viable
- more likely to induce cell mediated response, T-cell/memory cell formation, etc.

\({\bf{Inactivated~Vaccine~Subtypes:}}\)
- toxoid vaccine: inactive toxic compounds, ex. diptheria and tetanus
- subunit vaccine: bacterial/viral components
- conjugate vaccine: polysaccharide immunogenesis ability enhanced w/ chemical linkage to make it behave more like a protein
- inactivated vaccine: contains heat-killed pathogens

- adjuvants: compounds that increase antigen's effect on immune response, ex. alum salt
- may slow the rate at which the antigen is exposed to the system

Answer 2

\({\bf{Drawbacks~of~Vaccines:}}\)
- not all infectious agents can be made into a vaccine, ex. fungi and parasites [potential workaround: hybrid vaccines]
- may have harmful side effects [headaches, fever, fatigue, etc.]
- do not always work

\({\bf{Modern~Vaccine~Technology:}}\)
- shot-free vaccines, like patches/edible vaccines
- genetically engineered subunit vaccines
- naked DNA vaccines

Answer 3

Anyway, that's my tutorial, hope this was a useful resource.

Note: For those who wish to have a discussion about the merits of vaccination/anti-vaccination, please create a new question. I am willing to have respectful discussion but I would like to keep it off my tutorial. Thanks~