Solved by a verified expert:Epidemiology is the study of disease in populations. The severity of a disease outbreak depends on the infectious organism and the susceptible population. Vaccines present a limited exposure to the pathogen and result in a protective immune response. Vaccine development is a lengthy and very expensive process.In your role as a respected epidemiologist, you are asked for a professional opinion about development of a vaccine. Choose a good candidate disease (infectious organism) for vaccine development and explain why this expensive research will result in improvement of health in target populations (animal or human).Add an example of a disease which is not appropriate for vaccine development and explain your reasoning. For example, measles and related viruses (canine distemper and Newcastle disease virus, which infects birds, were good candidates for vaccine development because the organism (Paramyxovirus: Measles) is stable, very contagious, and causes serious disease. The parainfluenza virus 3 which causes common colds and coughs is not a good candidate because it usually does not lead to serious disease and infection does not result in lasting immunity. A vaccine against kennel cough (canine paramyxovirus 3) only offers short term protection.