Description: Segment 1 An introduction and diagrammatic explanation of the effect of infections such as smallpox on the host. There is a short history of how preventative medicine began using the story of Jenner who injected the eight-year-old James Phipps with cowpox. Statistics are shown to illustrate how effective immunisation has been in stamping out death from diseases such as smallpox. Diagrams are used to explain how antigens and antibodies change the constitution of the body. Viral infections are differentiated from bacterial infections and the process of 'active immunity' is explained. Time start: 00:00:00:00 Time end: 00:05:26:00 Length: 00:05:26:00 Segment 2 Artificial active immunisation is covered, showing how artificially injecting toxoids (toxoid vaccines) lead to the production of antitoxins which can be measured in the blood serum. Examples of diphtheria vaccinations are used to explain the phenomenon of primary and secondary responses as well as booster jabs. Artificial passive imunisation is also covered, which leads to passive immunity. Time start: 00:05:26:00 Time end: 00:10:23:18 Length: 00:04:97:18 Segment 3 The difference between active and passive immunity is explained in detail and there are many shots of laboratory work. The production of antiserum is shown. There is a shot of a horse having blood taken from it after being brought into a hyper-immune state by a series of innoculations. We can see the blood serum being refined and concentrated to make it suitable for injection into other organisms. There are shots of Tetanus antitoxin in large jars and being placed into ampoules under sterile conditions by technicians. We see how convalescence serum is obtained from a boy recovering from measles, then we see a baby in a doctor's surgery receiving an injection into its leg. Time start: 00:10:23:18 Time end: 00:17:09:00 Length: 00:06:46:42 Segment 4 A diagrammatic explanation that heterologous antisera is less productive than homologous antisera. Passive immunity from mother to new born is explained and illustrated by the fact that active immunisation of ewes protects lambs from contracting lamb dysentery. We see a mother taking her baby to a local health centre with a diphtheria poster outside. There is an explanation as to how toxoid vaccines (such as diphtheria and tetanus) are harvested and used in immunisation. We see diphtheria being cultured in vats to produce toxoids which are siphoned off into jars, filtered, treated with formaldehyde and bottled for incubation. We see a guineapig vaccinated. Sometimes a vaccine is absorbed with alum before use to make the substance more slowly absorbed - this method was discovered by the Wellcome laboratories. We see women on a production line bottling the vaccine. Time start: 00:17:09:00 Time end: 00:25:20:09 Length: 00:08:11:09 Segment 6 Vaccine production under sterile conditions is shown vaccines are packaged up and phials filled. The narration concludes by explaining the complexity of the subject of immunisation and summarises the differences between active and passive immunity. Pan over many Wellcome products available at this time. Time start: 00:32:27:00 Time end: 00:40:00:00 Length: 00:08:33:00