335 



vaccine. As of that date, no applications had been filed with the PHS 

 by pharmaceutical manufacturers for licenses to produce the Sabin 

 vaccine. The Health and Science Subcommittee of the House Com- 

 mittee on Interstate and Foreign Commerce, immediately held hearings 

 on the matter (March 16 and IT, 1961) ."" 



Several significant changes, detailed in these hearings, were made by 

 the PHS in dealing with the development and licensing of the Sabin 

 oral vaccine. The reorganization of the PHS in 1955 had provided for 

 the establishment of the Division of Biologies Control, charged with 

 keeping the PHS fully informed of the development of new biologi- 

 cals, and taking part in onsite industrial inspection of plants while the 

 new vaccine was being developed. 



By 1961, the Sabin vaccine had been licensed and extensively manu- 

 factured and used in Great Britain, the Soviet Union, and other Euro- 

 pean countries. The delay in American licensing can be attributed to 

 two factors: (1) the lack of a suitable U.S. population in which to test 

 the efficacy of the oral vaccine because of the extensive Salk vaccination 

 program; and (2) the cautious and deliberate response of PHS. 



Even during the early 1950's the Congress had encountered the con- 

 troversy over the relative merits of an oral (attenuated) versus a killed 

 (inactivated) vaccine. Most virologists agreed that an oral vaccine 

 would be cheaper to produce, would be easier to adminster, and would 

 provide longer immunity. Nevertheless much more research would be 

 needed before an oral polio vaccine could be licensed. For example, 

 the fact that an "attenuated virus' vaccine actually induced a mild 

 infection j^rovoked some question as to whether the virus might be- 

 come dangerously virulent after passage through the human intestine 

 and cause a polio epidemic in the community. Conversely, if the 

 whole community were vaccinated at the same time would the chain 

 of transmission of the disease be broken ? 



Profiting from experience with the Salk vaccine, the PHS antici- 

 pated research and potential requests for licenses for an oral vaccine. It 

 took precautions to maintain surveillance over the research clone on the 

 Sabin vaccine by the manufacturers. 



On June 30, 1958, the PHS established a Committee on Live Polio- 

 virus Vaccine. From that date until licensing, the committee met some 

 15 times. Numerous articles were published in scientific periodicals by 

 members of the committee as well as PHS officials to report to the 

 scientific community on progress and problems in the development of 

 the vaccine. PHS issued several interim reports and lists of proposed 

 standards to manufacturers, issued warnings about hast}' production, 

 attended international conferences treating the matter, and frequently 

 consulted with industry to discuss the safety and efficacy of the vaccine. 

 Thus, despite charges of a "polio vaccine gap" between the Unitecl 

 States and the Soviet Union, the PHS, cautious about potential haz- 

 ards, refrained from yielding to the pressure of public opinion. Gradu- 

 ally, each of the three strains of the Sabin vaccine was licensed. PHS 

 continued to maintain surveillance over the vaccine once distribution 



^ U.S. Congress. House. Committee on Interstate and Foreign Commerce. Polio vaccines 

 Hearings before a subcommittee of the • * ♦ on developments with respect to the manu- 

 facture of live virus polio vaccine and results of utilization of killed virus polio vaccine 

 Mar. 16 and 17, 1961, 87th Cong., 1st sess. (Washington, U.S. Government Printing 

 Office, 1961). 



