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By Helena Curtis; N. Sue Barnes; Adriana Schnek; Alicia Massarini

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5 percent of their genes. In 400 BCE Hippocrates identified the most widespread disease in Greece as phthisis and in so doing described classic signs of consumption or TB. ” The infected transmit the TB pathogen when they 40 allies and enemies cough, sneeze, or merely breathe, and dense population centers have always acted as breeding grounds. Today TB infects one-third of the world’s population, and humans, not cattle, serve as the reservoir. Bubonic plague, syphilis, and anthrax began appearing with regularity about 2000 BCE.

Manufacturers of salad dressings, coleslaw mixes, and mayonnaise now encourage the growth of lactic acid bacteria to produce an acidic tangy flavor and preserve the food. When bacterial contaminants did not produce a tasty, edible product, the ancients froze, smoked, or dried the food or added salt, sugar, or honey. These preservation methods inhibit bacteria’s growth by making water molecules unavailable for cellular reactions. Food producers still use these ancient methods, but they now also use chemicals to inhibit the growth of microbes in food.

1). Paleopathologists use fiber optics, X-ray imaging, and computerized tomography to see inside caskets without disturbing the contents. Only when they find evidence of damaged tissue do they open the casket and salvage DNA from a bit of tissue, bone, or tooth pulp. By comparing the ancient DNA with 38 allies and enemies that of present-day pathogens, scientists have identified the main bacterial diseases that have haunted society for millennia: anthrax, bubonic plague (Yersinia pestis), cholera (Vibrio cholera), diphtheria (Corynebacterium diphtheria), leprosy (Mycobacterium leprae), syphilis (Treponema pallidum), tuberculosis (TB) (M.

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