|MadSci Network: Medicine|
Hello, Thanks for your question. I think the best advice I can give about writing stories with a science base is to read about and understand the science you want to incorporate. By even asking this question, you have made it clear want to get the science right in your story, which is great. Learning about the science is a large undertaking, but all the good science novels I have ever read were written by people who had a good foundation in the area of science they were using within their stories. Have you read much about porphyria yet? The term encompasses a group of metabolic disorders that result from defects in the biosynthesis of heme. There are many types including 4 acute types, each of which represents a distinct genetic disorder. Some porphyrias are autosomal dominant, (i.e. you only need to inherit the defect from one parent in order to be affected), and others are autosomal recessive (i.e. you need to inherit the defect from both parents in order to be affected). The onset of these different types varies also, ranging from early childhood, to puberty, to adulthood. The symptoms of the various disorders can be quite different. Genetic disorders in general cannot be contagious. However, there can be triggers for an attack of a particular disease that one is predisposed to. In the case of porphyria, attacks can be triggered by the ingestion of certain drugs or hormones, or can be precipitated by fasting and dieting. Again, this probably varies for different types of porphyrias. So, in short, if we were to take the scenario you outlined in your question, I imagine you would have to have most people susceptible to the effects of a particular disease causing agent. The disease could have the symptoms you wanted (though make sure to check the biology of what you decide upon!). In this case, you might be able to incorporate the symptoms of porphyria you were thinking of originally. For example, perhaps a virus or bacteria could infect humans, and cause a vast overproduction of some compound that then causes sickness and/or death? In such a scenario, be sure to think about how the disease is transmitted from person to person, (e.g. is it inhaled, is it via touch, is it sexually transmitted, is there another host involved, for example an insect that transmits a pathogen, etc.), and how long the disease takes to cause death, or illness, etc. Reference to a basic textbook on epidemiology may help you get an idea of what to consider when "creating" a disease that might be universally contagious and which could go on to infect a large percentage of the population. If your background in science is not yet strong, perhaps a good idea would be to read a bit about diseases that have wrought devastation in the past. For example, the Great Plague or the Influenza pandemic just after the first world war. The history of such diseases may be helpful in planning a story such as yours. If you are looking for books on the subject of Plagues, just searching any book selling web site with the word "plague" should bring up more than enough titles. Perhaps your college library will stock at least some of these. Good luck with your writing!
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