Ch.17 Flashcards
(21 cards)
What are adjuvants?
Substances that increase the antigenicity of a vaccine.
What is contact immunity?
This occurs when a vaccinated individual infects those around them (with mild infection), and provide immunity beyond the vaccinated individual.
What are some pros of attenuated vaccinations?
- stimulates a strong immune response
- Vaccinated individual can infect those around them (with mild infection) and provide contact immunity.
Describe Attenuated vaccines
a. Viruses are raised for several generations in tissue culture cells until they lose virulence.
b. Bacteria are cultured under unusual conditions or genetically manipulated
c. Avirulent pathogen causes mild infection, but no serious disease. Viruses will infect host cells and replicate which stimulates an immune response.
What are the 2 types of immunization and what describe them
- Active immunization, the patient mounts a normal active response after contacting an antigen. Either naturally, (normal contact with full pathogen), or artificially (vaccination with modified pathogen).
- Passive immunotherapy, the patient acquires temporary immunity through receiving preformed antibodies.
What are the pros and cons of inactived vaccines?
Pro: Safer since they can’t replicate, revert or mutate, but “boosters” are necessary.
Cons: No contact immunity is gained
What is Herd immunity?
- The Protection provided when a majority of individuals (75%) are vaccinated.
- The pathogen cannot effectively spread through the population. Not enough individuals to serve as carriers/reservoir.
What is antigenicity?
The ability of an antigen to bind specifically with a group of certain products (T and B-cells) and stimulate an immune response.
What are toxoid vacines?
For some bacterial disease it’s best to have immunity for the offending toxin instead of the cell itself.
a. chemically or thermally modified toxins stimulate antibody mediated immunity
b. low antigenicity requires multiple boosters and reinoculations every 10 years
What is Immunization?
The administration of any antigenic inoculum
What are the 4 ways recombinant DNA technology could help improve/make vaccinations?
- Selectively deleting virulence genes from a
pathogen producing an irreversibly attenuated
microbe. - Production of large amounts of very pure viral or
bacterial antigens. - Genetically altered cell or virus used as a
recombinant vaccine. - Recombinant DNA is injected into the body, is
taken up, and triggers a cellular response.
What is a “wild type” virus?
When a modified virus, which was originally unharmful to humans, reverts back to a virus that can cause disease.
Describe anaphylactic shock
An extreme, often life-threatening allergic reaction to an antigen to which the body has become hypersensitive.
What are some cons of attenuated vaccinations?
- May cause disease in immunosuppressed people
- Pregnant women should not receive these vaccines
- Occasionally modified viruses actually revert back to wild type or mutate to a disease causing form.
What are the two types of inactivated (killed) viruses?
- Whole agents - deactivated but whole microbes
* Nonantigenic portion may cause painful inflammatory response. (Pertussis)
- Subunit – produced with antigenic fragments
NOTE: Important that antigen portions remain as similar to those of living pathogens as possible.
List a few of the safety issues regarding vaccinations.
Safety issues generally involve mild toxicity
1. Pain at the injection site lasting hours to days.
- General malaise and possible high fever
- Anaphylactic shock in reaction to a component of
the vaccine such as egg.
a. You should remain in the Dr’s office for
several minutes after a vaccination - Residual virulence discussed earlier.
What is titer?
The measurement of the levels of IgG and IgM in the blood of an individual.
What are combination vaccines?
Vaccines that combine antigens from inactivated pathogens and toxoids; they are then administered together.
Ex:
a. MMR – measles, mumps, rubella
b. Pentacel – diphtheria, tetanus, pertussis, polio, and Haemophilus influenzae.
What is a booster?
An additional dose of an immunizing agent, such as a vaccine or toxoid, given at a time after the initial dose to sustain the immune response elicited by the previous dose of the same agent
What is variolation?
The process of deliberately in-fecting young children with particles of ground smallpox scabs from children who had survived mild cases. By doing so, they succeeded in significantly reducing the population’s overall morbidity and mortality from the disease.
Define vaccination
The administration of antigenic material (a vaccine) to stimulate an individual’s immune system to develop adaptive immunity to a pathogen
