Study shows Black Death did not kill indiscriminately | Top News | Reuters
“A lot of people have assumed that the Black Death killed indiscriminately, just because it had such massive mortality,” anthropologist Sharon DeWitte of the University at Albany in New York, said in a telephone interview. 
People already in poor health often are more vulnerable in epidemics. “But there’s been a tradition of thinking that the Black Death was this unique case where no one was safe and if you were exposed to the disease that was it. You had three to five days, and then you were dead,” DeWitte said. The plague epidemic of 1347 to 1351 was one of the deadliest recorded in human history, killing about 75 million people, according to some estimates, including more than a third of Europe’s population.
DeWitte analyzed skeletons unearthed from the East Smithfield cemetery in London, dug especially for plague victims and excavated in the 1980s, for bone and teeth abnormalities that would show that people had health problems before they died of plague. She found such abnormalities in many skeletons, suggesting these people had experienced malnutrition, iron deficiencies and infections well before succumbing to the Black Death.