Meningitis is a relatively rare infection that affects the delicate membranes -- called meninges (men-in'-jeez) -- that cover the brain and spinal cord. Bacterial meningitis can be deadly and contagious among people in close contact. Viral meningitis tends to be less severe and most people recover completely without specific therapy. Fungal meningitis is a rare form of meningitis and generally occurs only in people with weakened immune systems.
The Black Death is thought to have originated in the arid plains of Central Asia, where it then travelled along the Silk Road, reaching Crimea by 1343. From there, it was most likely carried by Oriental rat fleas living on the black rats that were regular passengers on merchant ships.
The international effects of Black Death. Death and disease were familiar features of life in the Middle Ages, but previous epidemics were dwarfed by the arrival of the Black Death. It erupted out of central Asia to create a pandemic greater even than the Plague of Justinian 800 years earlier. Present in bubonic, pneumonic and septicaemic forms, the Black Death had killed millions by the time it finally declined. Europe may have lost a third of its people, China perhaps half.