Howard J. Shaughnessy

Immunogenicity of poliomyelitis vaccine prepared with ultraviolet irradiation and mild heat.

Summary 1. Poliomyelitis virus of high titer in the form of a freshly filtered tissue culture preparation, can be inactivated by ultraviolet irradiation in centrifugal filmers. 2. Inactivation of the virus preparations by a combination of ultraviolet irradiation and exposure to mild heat for several days yields vaccine of good potency. In this procedure there is a margin of safety between complete inactivation and appreciable loss of antigenicity. 3. Experience thus far indicates a degree of consistency and reproducibility for the method described. 4. Vaccines made by a combination of ultraviolet irradiation and mild heat appear to retain their antigenicity for at least 7 months.

Studies on production of antipoliomyelitis serum in rabbits.

Summary Type specific neutralizing antibodies were produced in rabbits inoculated with the 3 types of poliomyelitis virus grown in tissue culture. Rabbits were successfully immunized by repeated intravenous or intramuscular inoculations of active or ultraviolet irradiated virus suspensions. The possibilities of a rabbit test for the assay of poliomyelitis vaccine are discussed.

PRODUCTION OF POTENT INACTIVATED VACCINES WITH ULTRAVIOLET IRRADIATION: II. AN ABBREVIATED PRELIMINARY REPORT ON STERILIZATION OF BACTERIA AND IMMUNIZATION WITH RABIES AND ST. LOUIS ENCEPHALITIS VACCINES

antigenicity, while the usual methods of inactivation (heat and various chemicals) unduly destroy the antigenic properties. Furthermore, the conditions of irradiation were standardized with respect to intensity of irradiation, distance from energy source, film thickness and time of exposure, so that experiments could be repeated with consistent results. This paper is a preliminary condensed report presenting results using the new technic of ultraviolet irradiation on (1) inactivation of various bacteria and viruses and (2) immunization with avirulent rabies and St. Louis encephalitis vaccines. The complete paper will appear elsewhere. The lethal effect of ultraviolet irradiation on bacteria and viruses has been demonstrated repeatedly. Com¬ paratively few studies have been made of the anti¬ genicity of ultraviolet irradiated bacteria and viruses.2 Since 1937 there have been reports by Hodes, Lavin and Webster,3 by Webster and Casals,4 by Salk and