Thundering herd

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.

Precisely because most children are immunised, he tells parents that it is probably safe to skip or delay jabs for their offspring. This strategy amounts to “hiding in the herd”, he says delicately, as he sips a late-afternoon coffee near his surgery. Put another way, his patients worry more than most about possible side-effects from vaccinations, above all the (thoroughly discredited) claim that vaccines cause autism. Dr Bob—as he is known to fans of “The Vaccine Book”, his best-selling guide to “selective” immunisation—does not say that worried parents are right. He just thinks that, on balance, they can safely indulge their anxieties by “taking advantage of the herd all around them.” When pushed, he makes “no claim” that the alternative vaccine plans that he offers (involving fewer jabs, or jabs administered over a longer period than most doctors recommend) are safer. He concedes that if everyone refused vaccinations, some diseases would roar back.