The PHS Act emphasizes the importance of manufacturing control for products that cannot be defined. This is extremely important for the safety of our blood supply, our vaccines, especially our live viral vaccines, e.g. varicella and polio. The consistency, safety, efficacy and stability of these products, especially vaccines, are dependent on clearly defining and adhering to the processes described in an application, because the important structural features of the final product cannot be defined and there is an increased risk of the introduction of adventitious agents. The PHS Act provides the agency with a licensing mechanism to confer approval of biological products and provides additional assurance to people receiving blood products and the millions of children being immunized each year to protect from childhood diseases. The PHS Act also provides authority to immediately suspend licenses in situations where there exists a danger to public health. This statute also allows us to prepare or procure products in the event of shortages and critical public health needs, and authorizes the creation and enforcement of regulations to prevent the introduction or spread of communicable diseases in the US and/or between states. This law also provides important flexibility in regulation of biotechnology products, which facilitates the introduction and development of new medicines. | 
