大象传媒

Treating, curing and preventing disease - OCR Gateway Herd immunity

Pathogens are everywhere. The body has evolved defences that act to prevent pathogens entering it. If a pathogen does enter the body then the immune system helps to fight it off.

Part of Biology (Single Science)Global challenges

Herd immunity

Following a vaccination, a person can become immune to the specific disease. This gives protection against illness in an individual. The majority of the population must be vaccinated against serious diseases, which can reduce the chance of people coming into contact with specific , leading to .

Following a vaccination, a person can become immune to the specific disease This immunity gives protection against illness in an individual.
Chart showing cases of illness per year before a vaccine introduced.
A graph showing measles notifications in 1000s from 1950 to 2014.

Question

Explain what happens to the number of measles cases after 1968.

Question

Describe how the introduction of the new MMR vaccine affected the cases of measles recorded.