HYPERIMMUNE VACCINAL GAMMA GLOBULIN

Hyperimmune vaccinal gamma globulin was prepared from the blood of 320 adult donors who showed maximal skin response to smallpox vaccination and who donated 1 pint of blood each, 4 to 6 weeks after such successful vaccination. Hyperimmune vaccinal gamma globulin contains neutralizing antibodies in excess of those found in ordinary gamma globulin. While with the present tests available it is not possible to accurately make a quantitative comparison, it is likely that the antibody content of hyperimmune vaccinal gamma globulin is at least threefold that of ordinary gamma globulin. In a group of 75 individuals intimately exposed to smallpox and vaccinated after exposure, 8 cases and 3 deaths occurred. Among 56 individuals who received identical vaccination followed by prophylactic doses of hyperimmune vaccinal gamma globulin, there were 2 secondary cases, with 1 fatality. Both groups were comparable from the standpoint of proportionate distribution of susceptible individuals and the severity of exposure to disease. While the number of contacts in each group was too small to warrant drawing a definite conclusion, it appeared to be established in the direction of increased protection following administration of passive immunity in the form of hyperimmune vaccinal gamma globulin. It would appear that the experience so far is encouraging enough to continue and to expand the use of hyperimmune vaccinal gamma globulin in the prophylaxis and therapy of serious dermal complications of smallpox vaccination.