Contrary to what baby boomers might assume, the term "conscientious objector" didn't originate with the Vietnam War. It was first used in the late 19th century to describe opponents of England's mandatory smallpox vaccinations, who received special exemption from the inoculations.
Their opposition to the vaccine was as shortsighted, and as unfounded in science, as the objections of parents today who refuse to recognize the importance of inoculation not just to their children but to public health. As it happens, the popular embrace of the smallpox vaccine eradicated the deadly disease worldwide by the late 1970s. Shortly afterward, polio was eliminated in the United States after a decades-long immunization campaign.
Yet several other diseases — not as deadly as smallpox and polio but still capable of killing — have been making comebacks in recent years as increasing numbers of parents decide that vaccination is dangerous. It started with the now-discredited claims of a British doctor who published a faulty study purportedly showing a link between vaccines and autism.
As The Times has reported, there were nearly 9,500 cases of whooping cough last year in California alone, the most in 65 years. Cases of other diseases — measles and Hib — are rising, though in far smaller numbers. Many measles cases are "imported" from countries where the disease is more prevalent, often by unvaccinated U.S. residents who return from foreign travel.