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Measles vaccine immunity
Measles is a communicable disease caused by a pathogen. Vaccinations help reduce the spread of measles.
Describe how the measles vaccine helps a person to become immune to the measles pathogen.
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Marking points
- 1 Describes the vaccine as containing dead/inactive or weakened/attenuated measles pathogen, or measles antigens.
- 2 States that white blood cells produce antibodies.
- 3 Explains that the antibodies are specific to measles.
- 4 States that memory cells are formed.
- 5 Explains that a later exposure produces antibodies faster or in larger quantities.
Full-mark answer
The vaccine contains inactive or weakened measles virus, or its antigens. Lymphocytes respond by making antibodies that are specific to the measles antigen, and memory cells are formed. If the person is exposed to measles later, the memory cells cause the specific antibodies to be produced more quickly and in larger quantities, destroying the pathogen before illness develops.
Why this answer loses marks
The vaccine contains dead measles, so phagocytes make antibodies.
The vaccine contains harmless pathogen material or antigens, antibody-producing white blood cells are not phagocytes, and immunity also needs memory and a faster later response.