Vaccines

Vaccines

ways viruses can spread

The air

Direct contact

Water

concerntration of antibodies after infection

primary infection 0-20 days

secondary infection 20-40 days

how vaccines work

• The syringe injects a weak or dead version of the pathogen
• The white blood cells in the body release pathogens with complementary fit to the pathogens
• The antibodies then attach onto the pathogen's surface
• The white blood cell then performs phagosytosis (where it engulphs/digests the pathogen)

link

Herd immunity

How it works

No one is vaccinated the disease spreads through the population

Some of the population is vaccinated so the disease spreads less

Most of the population is vaccinated so the spread is contained

examples of herd immunity

In 1942 Diptheria had 50,804 cases and after the vaccine was introduced cases reduced by 99.9%

In 1957 Pertussis had 92,407 cases and after the vaccine was reduced cases reduceds by 96%

In 1968 Measles had 460,407 cases and after the vaccine was reduced by 99.9%