Population history of indigenous peoples of the Americas scope of the epidemics over the years was tremendous, killing millions of people—possibly in excess of 90% of the population in the hardest hit areas—and creating one of "the greatest human catastrophe in history, far exceeding even the disaster of the Black Death of medieval Europe", which had killed up to one-third of the people in Europe and Asia between 1347 and 1351. One of the most devastating diseases was smallpox, but other deadly diseases included typhus, measles, influenza, bubonic plague, cholera, malaria, tuberculosis, mumps, yellow fever and pertussis, which were chronic in Eurasia. This transfer of disease between the
Early-onset Alzheimer's disease 3.5% of total Alzheimer's disease, it has presented a useful model in studying various aspects of the disorder. Currently, the early-onset familial AD gene mutations guide the vast majority of animal model-based therapeutic discovery and development for AD. Alzheimer's disease (AD) is the most common cause of dementia and usually occurs in old age. It is invariably fatal, generally within 10 years of the first signs. Early signs of AD include unusual memory loss, particularly in remembering recent events and the names of people and things, logopenic primary progressive aphasia. As the disease progresses, the patient exhibits more serious problems,