Sara Martín reads bedtime stories with her children. When the kids were younger, she says, staying up to date on their frequent immunizations was tough, because of cost and transportation issues.
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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.
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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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Writer Roald Dahl and his wife, actress Patricia Neal, with two of their children, Theo and Chantel Sophia "Tessa." The photo was taken a few years after oldest daughter, Olivia, died of measles.
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A nurse administers an experimental Ebola vaccine Monday at Redemption Hospital in Monrovia, Liberia. Researchers aim to give shots to 27,000 people during the large trial.
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