Of Microbes and Mock Attacks:

Of Microbes and Mock Attacks: Years Ago, The Military Sprayed Germs on U.S. Cities

Between Sept. 20 and Sept. 27 of 1950, a Navy mine-laying vessel cruised the San Francisco coast, spraying an aerosol cocktail of Serratia and Bacillus microbes – all believed to be safe – over the famously foggy city from giant hoses on deck, according to declassified Army reports. According to lawyers who have reviewed the reports, researchers added fluorescent particles of zinc-cadmium-sulfide to better measure the impact. Based on results from monitoring equipment at 43 locations around the city, the Army determined that San Francisco had received enough of a dose for nearly all of the city’s 800,000 residents to inhale at least 5,000 of the particles.

Two weeks after the spraying, on Oct. 11, 1950, Mr. Nevin checked in to the Stanford Hospital in San Francisco with fever and other symptoms. Ten other men and women checked in to the same hospital – which has since been relocated to Stanford University in Palo Alto, Calif. – with similar complaints. Doctors noticed that all 11 had the same malady: a pneumonia caused by exposure to bacteria believed to be Serratia marcescens. Mr. Nevin died three weeks later. The others recovered. Doctors were so surprised by the outbreak that they reported it in a medical journal, oblivious at the time to the secret germ test.