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
The Man Who Mistook His Wife for a Hat (opera) the piano, the actor actually playing if possible. The plot concerns the investigation by a neurologist of the condition of a singer who suffers from visual agnosia. According to the liner notes, Morris, Rawlence, and Nyman had to spend much time convincing the real Mrs. P. (whose husband is implied to have been a known name) that they were not proposing a musical (her word) that would trivialize her late husband's situation in order to gain her consent. Rawlence made a film version in 1987. It made brief omissions from the music (most notably the self-referential line, "That's Nyman! Can't