HRR: vaccines Flashcards
(44 cards)
What is passive immunization?
Immune or effector cells are transferred from an immune host to a naïve one.
What is active immunization?
Immune response is stimulated in the person being protected.
What is the goal of vaccination?
Inducing pathogen specific primary immune responses that result in memory B and T cells to allow faster, stronger secondary response and prevent disease following exposure.
What is attenuation?
Attenuation refers to the process of reducing the virulence of a pathogen.
What are pros of live-attenuated vaccines?
Longer antigenic challenge, induction at appropriate site, more antigens, and T cell dependent. All of this leads to stronger immunization.
What is herd immunity?
So many immune individuals in a group that a pathogen cannot sustain a chain of transmission within that group.
Who does herd immunity benefit?
Those who cannot get vaccinations, such as newborns, pregnant women, and immunocompromised people.
What is R0?
The average number of new infections started by an infected individual during the course of their illness.
What portion of the population needs to be vaccinated to break the chain of infection?
1 – (1/R0).
What are uncertainties of herd immunity?
Chronic carriers or common sources of contamination, like fomites.
What are adjuvants?
Substances added to vaccines to enhance immune response.
What are ways in which adjuvants work?
- Aggregate antigen
- Inducing inflammation.
What are examples of adjuvants in the US?
- Aluminum hydroxide/phosphate
- Lipid emulsions like AS01B or MF59
- Synthetic DNA sequences like CpG 1018.
What kinds of vaccines require adjuvant?
Non-living vaccines.
Which vaccines have adjuvants?
Hep A and B, DTaP, Hib, HPV.
Describe the hepatitis B virus.
Contains purified HBsAg protein and an adjuvant.
What are advantages of HepB vaccine?
No chance of disease transmission and well-defined microbial components.
What are disadvantages of HepB vaccine?
Limited number of epitopes means some people may not respond to the vaccine, and those with severe yeast allergies cannot have the vaccine.
Describe the RSV active vaccine.
A recombinant vaccine containing RSV fusion protein in the pre-fusion conformation.
Describe RSV passive vaccine.
Vaccine containing RSV antibodies.
Who is the RSV passive vaccine given to?
Infants younger than 8 months who are entering RSV season without maternal antibodies.
Describe the rotavirus vaccine.
A live attenuated vaccine given orally and induces immunoprotective IgA.
What is unique about the scheduling of rotavirus vaccine?
There is no catch-up. If the vaccine is missed by 8 months old, you just skip it.
Describe DTaP vaccine.
Contains diphtheria and tetanus toxins as well as pertussis toxoid.
