polio rate of casses vs vaccination coverage 1980-2015 Part 1: Based on the information presented in the graph, describe the correlation between polio cases and vaccine coverage. Cite data from the graph to support your answer.
Part 2: A classmate is having trouble understanding how vaccines provide immunity. Using what you have learned in the lesson, write an explanation to share with your classmate about how vaccines work with your immune system to protect you against infection.