The list of infectious diseases that spread from the Old World to the New is long; the major killers include smallpox, measles, whooping cough, chicken pox, bubonic plague, typhus, and malaria (Denevan, 1976, p.
Dog owners tend to live longer and far better after a heart attack or stroke. Researchers found that there were 33% lesser chance of death to occur in a person who is the owner of a dog after a heart attack. Dogs tend to calm the humans.
