Vaccines

Question 1

Live attenuated vaccine

Answer 1

live microbes are weakened by growing them for many generations in animals or tissue cultures.
Examples – oral polio, MMR, zoster

Question 2

Inactivated vaccine

Answer 2

whole organisms that have been killed. Stimulate the immune system but do not cause disease.

Examples – polio, influenza, Hepatitis A

Question 3

Inactivated toxins

Answer 3

some bacteria cause disease by producing toxins. Inactivated toxins are used to prevent disease.

   Examples – tetanus, diphtheria

Question 4

Subunit vaccines

Answer 4

use only a part of the bacterium or virus.

   Examples – typhoid, hepatitis B, 
      pertussis, meningitis

Question 5

Conjugate Vaccines

Answer 5

link proteins from a second organism to the outer coat of the bacteria. Allows a baby’s immune system to recognize the bacteria.

 Example – Haemophilus influenzae - b
   (Hib), pneumococcus

Question 6

Edible Vaccines

Answer 6

genetically engineered potatoes, bananas, and tomatoes that, when eaten, will initiate an immune response against harmful intestinal bacteria and viruses.
Examples – E. coli enterotoxin, rabies

“Plantibodies” – specific antibodies made in plants
Example – strep mutans (tooth decay)

Question 7

To vaccinate or not to vaccinate?

  Issues to consider:

Answer 7

life-long natural immunity vrs need for boosters

effects of disease vrs side effects of vaccine

ease of vaccination

timing of vaccination

cost

true contraindications to vaccination

Question 8

Invalid Contraindications to Vaccination

Answer 8

Minor illness
Mild/moderate local reaction or fever following a prior dose
Antimicrobial therapy
Disease exposure or convalescence
Pregnancy or immunosuppression in the household
Premature birth
Breastfeeding
Allergies to products not in vaccine
Family history (unrelated to immunosuppression)

Question 9

Valid Reasons to not vaccinate

Answer 9

Anaphylactic reaction
      Prior high fever 
      Immunodeficiency
      Pregnancy
      Significant acute illness

Question 10

HIV Vaccine

Answer 10

Inactivated monkey viruses can cause AIDS antibodies in both infant and adult monkeys
Arecombinant vaccines – alter an organisms’ genetic structure by removing a key gene or by modifying the DNA.
Since 1987, 28 vaccines have been tried.
Trials of different proteins from HIV and different delivery systems are underway.

Question 11

HIV Vaccine Problems

Answer 11

HIV hyper-variability
Immune correlates of protection are still unknown
Relevant animal models are lacking
Clinical trials are long and costly

Question 12

Malaria Vaccine

Answer 12

Malaria causes 3 million deaths annually worldwide
Vaccines studied for 50 years!
Vaccine research also using arecombinant technology
P. falciparum chromosome has been mapped
Phase I/II trials underway

Question 13

Tuberculosis Vaccine

Answer 13

1 for infectious disease deaths

Two billion infected, three million die per year worldwide.
Complete genetic blueprint of M. tuberculosis has been determined.
BCG – vaccine has been available and used worldwide for many years, variably effective.
Vaccine in development, not in trials yet.

Question 14

Treating Cancer with Vaccines

Answer 14

Isolate proteins from the surface of melanoma cells and using thee antigens to provoke the immune system into producing killer T-cells against the cancer.
Also tried on renal carcinoma
Measles vaccine-myeloma

Question 15

Alzheimer’s Disease

Answer 15

Result of formation of amyloid B peptide plaques in brain

Immunization of mice with amyloid B prevented the formation of plaques and resultant cellular damage