California’s anti-vaccine brigade and the dark side of individualism
DR BOB SEARS, a paediatrician from Orange County, California, does not like to call his patients “free-riders”. True, he specialises in treating vaccine-sceptics, those families who resent being told to immunise their children against nasty diseases, from measles to whooping cough. It is also the case that, as a trained doctor, he believes that immunisation works. He agrees that some scary illnesses have almost vanished in America because more than 90% of children are inoculated against them, creating a herd immunity that leaves diseases with few places to lurk. Yet he differs from many doctors in the conclusion that he draws from that success.
This article appeared in the United States section of the print edition under the headline “Thundering herd”

From the September 26th 2015 edition
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