Since the discovery by Stokes, Bauer, and Hudson (1) that yellow fever may be transmitted to monkeys, laboratories for further studies of the disease have been established in various parts of the world. In many of these places accidental infections have occurred which have been mentioned only casually in published reports.
It has been suggested to us that a fuller account of some of the infections might be appreciated by other laboratory workers and by the medical profession. We have prepared, therefore, a résumé of the histories of four cases among Americans, in Bahia, Brazil; at least three of the patients unquestionably were infected in the laboratory. As far as we know, none of the Brazilian personnel has become infected.
It would be of value to know how each laboratory infection is acquired and the strain of virus that is responsible. On these points exact data are usually not obtainable.