The media are usually blamed for fuelling health scares. As the number of anthrax cases in the United States rose last week—and as a biological attack by terrorists increasingly seemed the most likely cause—newspapers and television stations played a calming role.

The anthrax story began on 2 October when Bob Stevens, 63, a magazine picture editor working in in the American Media building in Boca Raton, Florida, walked into the JFK Medical Centre in Atlantis with fever and confusion. When news broke that he had been diagnosed as having pulmonary anthrax, public fear turned in some cases to hysteria. By Tuesday this week, there had been reports of anthrax in Florida, New York, Nevada, and Washington DC, and the number of people affected had reached double figures, of whom one—Mr Stevens—had died. A top US senator had been targeted, and the baby son of an ABC news employee has tested positive for …