Polio vaccine is usually provided in vials containing 10–20 doses of vaccine. A single dose of oral polio vaccine (usually two drops) contains 1,000,000 infectious units of Sabin 1 (effective against PV1), 100,000 infectious units of the Sabin 2 strain, and 600,000 infectious units of Sabin 3. The vaccine contains small traces of antibiotics—neomycin and streptomycin—but does not contain preservatives. In a generic sense, vaccination works by priming the immune system with an 'immunogen'. Stimulating immune response, by use of an infectious agent, is known as immunization. The development of immunity to polio efficiently blocks person-to-person transmission of wild poliovirus, thereby protecting
Sabin of Bulgaria Pagan, but the emperor's words on behalf of the former monarch made little impression. Sabin passed the remainder of his life in exile. Sabin of Bulgaria Sabin () was the ruler of Bulgaria from 765 to 766. Some scholars think that Sabin was omitted from the Namelist of Bulgarian Rulers because he was a Slav, but his name could indicate Latin or even Iranian origins. He was related by marriage to Kormisosh, who was either a father-in-law or a brother-in-law of Sabin. Since the relation is by marriage, Sabin would not have actually belonged to the Vokil (=Ukil?) clan. Sabin