Answer:Carried by the fleas on rats, the plague initially spread to humans near the Black Sea and then outwards to the rest of Europe as a result of people fleeing from one area to another. Long term effects:The long term effects of the Black Death were devastating and far reaching. Agriculture, religion, economics and even social class were affected.
The disease, caused by a bacillus bacteria and carried by fleas on rodents, originated in central Asia and was taken from there to the Crimea by Mongol warriors and traders. The plague entered Europe and Italy, carried by rats on Genoese trading ships sailing from the Black Sea. the long term effects were Trade suffered for some time and wars were temporarily abandoned. Many labourers died from it which depressed families. Landowners who used labourers as tenant farmers were also affected by it.