Gamma globulin not effective in prophylaxis of epidemic respiratory infections.

During the course of an experiment on the prophylactic value of gamma globulin against infectious hepatitis, an unexpected opportunity occurred to test its value in an outbreak of an influenza-like respiratory infection. The explosive nature of the outbreak and the uniformity of clinical and laboratory findings suggested a single etiologic factor, presumably a virus, since extensive search for a bacterial agent was unsuccessful. Eight samples of serum taken from as many patients about two to three weeks after the acute illness were sent to Dr. Charles A. Janeway, who consented to have them analyzed for influenza A and B antibodies. No significant titer of antibodies was found. The etiologic factor, unfortunately, is therefore not known. Between Dec. 16 and Dec. 20, 1945 approximately one third of the inmates (aged 5 to 66 years) of each of twenty-five cottages were injected with gamma globulin. The dose varied from approximately 4 cc.