Biological products. — Medicinal preparations for animals containing microorganisms and their products, including sera, vaccines, antigens and antitoxins, which are, in turn, defined as follows:
(1) Vaccines. — Any material for preventive inoculation, as a suspension of dead or inactivated bacteria, or of live bacteria of low virulence which, on introduction into the body of an animal, produces immunization against the disease caused by live bacteria through the formation of antibodies.
(2) Antigen. — Any substance which when introduced into the blood or tissues of an animal incites the formation of antibodies.
(3) Antiserum. — A serum that contains antibodies obtained from an animal that has been subjected to the action of antigen either by injection into the tissues or by infection.
History —May 25, 1961, No. 12, p. 40, § 2.