Measles is a serious disease - AQA - GCSE Biology Combined Science - Question 5 - 2018 - Paper 1
Question 5
Measles is a serious disease. A person can die from measles.
Table 3 shows the number of medically confirmed cases of measles in England and Wales between 2012 and ... show full transcript
Worked Solution & Example Answer:Measles is a serious disease - AQA - GCSE Biology Combined Science - Question 5 - 2018 - Paper 1
Step 1
Suggest one reason why the actual number of cases of measles in England and Wales might be higher than is shown in Table 3.
96%
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Answer
Not everyone would go to the doctor; some cases might remain unreported or misdiagnosed.
Step 2
Calculate the percentage decrease in the number of medically confirmed cases of measles between 2012 and 2015.
99%
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Answer
To calculate the percentage decrease, use the formula:
Explain why vaccinating a large proportion of the population reduces the spread of the measles virus.
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Answer
Most people are immune, so they do not become infected. This leads to fewer chances for the virus to spread as there are less non-immune individuals available for infection.
Step 4
Explain the differences between antibody production after the vaccine injection and after exposure to the measles virus.
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After vaccination, the concentration of measles antibodies increases rapidly and remains elevated for a longer period compared to natural infection, where the response is slower and may not achieve as high a concentration. Specifically, Figure 8 shows that the antibody concentration peaks significantly higher and lasts longer after vaccination than after exposure to the virus.
