Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person...

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Lecture 15 Vaccines

Transcript of Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person...

Page 1: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

Lecture 15

Vaccines

Page 2: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

History

• 1717- Turkey- smallpox from sick person into veins of well person

• Variolation- mortality rate- 1%

• Edward Jenner received this treatment at age of 8

Page 3: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

Edward Jenner

• Observed milkmaids who became infected with cowpox, did not get smallpox

• Experiments- inoculated people with cowpox in order to prevent smallpox infection

• Vaccination: Vacca=cow

• Vaccine=

• Smallpox eliminated worldwide

Page 4: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

Vaccines

• Prevention can control many communicable diseases

• Bacterial diseases can often be treated with antibiotics, if prevention fails

• Viral diseases, not easily treated

• Vaccination only feasible means of controlling viral diseases

• Herd immunity=

Page 5: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

Types of Vaccines

1. Live attenuated vaccines

2. Inactivated vaccines

3. Toxoid vaccines

4. Subunit vaccines

5. Conjugate vaccines

6. DNA vaccines

7. Recombinant vector vaccines

Page 6: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

Attenuated whole-agent vaccine

• Use living, but weakened microbes

• More closely mimic an actual infection

• generally life-long immunity

• 95% effective for many vaccines

Page 7: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

Inactivated whole-agent vaccine

• Use microbes that have been killed

• Still provokes immune response

Page 8: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

Toxoid vaccine

• Inactivated toxins

• Remember- toxins are produced by some bacteria and these are what cause the disease

Page 9: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

Subunit vaccine

• Use only the part of the antigen that stimulates a strong immune response

• Safer- can not reproduce in the recipient

• Also, little or no extraneous material, and therefore less side effects

Page 10: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

Conjugate vaccine

• Some types of vaccines use polysaccharides

• Child’s immune system do not respond well to polysaccharides until 15-24 months

• Polysaccharides combined with another protein to make vaccine

Page 11: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

Nucleic acid vaccines

• Depend on ability of some cells to:

– take up and translate foreign DNA

– display the resulting proteins, inducing a strong immune response

• One has been approved for humans

Page 12: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

Development of new vaccines

• Vaccines most desirable method of disease control

• Early successful vaccines cultured in animals• With cell culture- could make vaccines that

would not grow on anything but human cells• Some vaccines do not need cell culture-

recombinant vaccines and DNA vaccines• Plant potential source for vaccines• In future- possibility for vaccines to treat

addiction, Alzheimer's, disease and cancer

Page 13: Lecture 15 Vaccines. History 1717- Turkey- smallpox from sick person into veins of well person Variolation- mortality rate- 1% Edward Jenner received.

Safety of vaccines

• Sometimes possibly to cause the disease while trying to prevent it

• Risk considered worthwhile

• Public reactions to such risks has changed

• Some believe connection between autism and MMR vaccine

• No studies have shown evidence of this