1. The Black Death

2. The Black Death was one of the most disastrous epidemics in our history, resulting in the deaths of an estimated 75 to 200 million people in asia and Europe. At its most deadly in Europe in the years 1346–1353. 
Causes: Though there were several ideas/theories as to the origin of the Black Death, analysis of DNA from victims in northern and southern Europe published in 2010 /2011 indicates that the pathogen responsible was the ‘Yersinia pestis bacterium’, probably causing several forms of plague.

3. First discovered/ Origin :The Black Death is thought to have originated in Central Asia, where it then travelled along the Silk Road, arriving in Crimea by From there, it was most likely spread by ‘Oriental rat fleas’ living on the black rats that were commonly found on merchant ships. Spreading throughout the Mediterranean and Europe, the Black Death is estimated to have killed an incredible 30–60% of Europe's total population. In total, the plague may have reduced the world population from an estimated 450 million down to 350–375 million in the 14th century, A massive decrease . The world population as a whole did not recover to pre-plague levels until the 17th century. The plague recurred occasionally in Europe up until the 19th century.

4. Known as:The black death goes by many other names such as "Great Mortality or the "Great Plague".
Europe:The disease, caused by Yersinia pestis, is enzootic which is commonly present in populations of fleas carried by ground rodents found in mainly Central Asia, Kurdistan, Western Asia, Northern India and Uganda.
The plague reached Europe in several places , entering Sicily in October 1347, carried by twelve ‘Genoese galleys’. Galleys from Kaffa arrived in both Genoa and Venice in January 1348, but it was the outbreak in Pisa a few weeks later that was the entry point to northern Italy. Towards the end of January, one of the galleys expelled from Italy arrived in Marseille .From Italy, the disease spread northwest across Europe, hitting France, Spain, Portugal and England by June of 1348, then turned and spread east through Germany and Scandinavia from 1348 to  It was introduced in Norway in 1349 when a ship landed at Askøy, then spread to Bergen and Iceland. Finally it spread to north western Russia in The plague was less common in parts of Europe that had smaller trade relations with their neighbours, including Poland, the majority of the Basque Country, isolated parts of Belgium and the Netherlands, and isolated alpine villages throughout the continent . The middle East was far worse affected with huge population decreases and Social and Economic structures facing serious problems

5. Symptoms
Modern accounts of the plague are often varied or not specific/improper. The most common symptom was the appearance of ‘buboes’ in the groin, the neck and armpits, which oozed pus and bled when opened. This was soon followed by serious fever and vomiting of blood. Most victims died two to seven days after initial infection. Freckle-like spots and rashes, which could have been caused by flea-bites, were identified as another possible sign of the plague.
Sources say that ; ‘It is said that the plague takes three forms. In the first people suffer an infection of the lungs, which leads to breathing difficulties. Whoever has this corruption or contamination to any extent cannot escape but will die within two days. Another form...in which boils erupt under the armpits,...a third form in which people of both sexes are attacked in the groin.’

6. -The three types of plague are the result of the route of infection: bubonic plague, septicemic plague, and pneumonic plague. Bubonic plague is mainly spread by infected fleas from small animals.
- It may also result from exposure to the body fluids from a dead plague infected animal. In the bubonic form of plague, the bacteria enter through the skin through a flea bite and travel via the lymphatic vessels to a lymph node , causing it to swell.
-Diagnosis is made by finding the bacteria in the blood, sputum, or fluid from lymph nodes.
-Prevention is through public health measures such as not handling dead animals in areas where plague is common. Vaccines have not been found to be very useful for plague prevention. Several antibiotics are effective for treatment including streptomycin, gentamicin ,and doxycycline.
- Without treatment it results in the death of 30% to 90% of those infected. Death, is normally within ten days. With treatment the risk of death is around 10%.Globally in 2013 there were about 750 documented cases which resulted in 126 deaths. The disease is most common in Africa.