Vaccination and other Immunization
Prevention and Therapy of Infections
• Most of the damage to cells during infections occurs very early, often before the clinical
symptoms of disease appear.
o This makes drugs treatment of infection irrelevant in many cases. (Drug
treatments against viral disease are not really working, they are pretty much
o Prevention of infection is better.
Vaccines are used for preventions.
What is a Vaccine?
Vaccines are harmless agents, perceives as enemies
Trigger active immunity, stimulating the body to defend itself
o Provide protective immunity against a potential pathogen
Milestones in Immunization
o Sniffing of smallpox Crust in China
Variolation: inoculation with the wild type smallpox. The difference
between variolation and vaccination is that vaccination is an agent;
variolation is a virus that causes the disease.
o Turks started to use variolation
o England introduce variolation
1796 o Edward Jenner discovers a safe smallpox vaccine. This vaccine has been used
for over 200 years. When we were able to eradicate small pox from the world, we
were able to use the same thing. This disease killed 300 million people every 100
hundred years. This was a huge success in terms of stopping this disease.
1885 Rabies vaccine
o In 1885 Louis Pasteur developed the first attenuated vaccine – against rabies virus
o Attenuation was achieved by creating a virus strain that were less virulent for humans.
Modern Era of the Vaccine
o 1920s- Diphtheria and Tetanus: secretes some toxins from its cells, this