This World Health Organization map shows the percent of the population vaccinated for measles in each country in 2013. Dark green is at least 90 percent. Light green is 80 to 89 percent. Orange is 50 to 79 percent. Red is less than 50 percent.
Courtesy of WHO
The KinderCare Learning Center in Palatine, Ill., where five infants have been diagnosed with measles. Officials are trying to track down the source of the infection.
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Leah Russin, of Palo Alto, Calif., holds her son, Leo, 16 months, as she speaks Wednesday at a news conference in support of proposed state legislation that would require parents to vaccinate all school children.
California is one of 20 states that allow parents to opt out of vaccination requirements for reasons of "personal belief." About 10 percent of students in the Santa Monica-Malibu school district are not immunized.
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Dr. Eric Ball examines a healthy 5-day-old patient in his office in Ladera Ranch, Calif. Ball and colleagues decided this week to take only patients whose parents follow the recommended vaccine schedule.
Courtesy of Eric Ball
Jackie Carnegie immunizes Mabel Haywood in a Colorado Health Department immunization van in 1972. Shots for measles and other infectious diseases were offered.
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