2. Medieval World

3. Black Death Caused by the bacterium Yersinia pestis, which still circulates among humans After genetic material from four London victim’s teeth were extracted, teams of researchers have sequenced 99% of the plague’s genome (2011). First big pandemic with disseminated Yersinia pestis in humans

4. Black Death – called so due to the blackened skin of the victims A pneumonic infection, highly contagious, which could be transmitted via inhalation, ingestion, or even a slight abrasion on the skin. Lung lesions occur, heart and kidneys turn to fatty goo, and death usually results from heart failure The walls of blood vessels hemorrhage

5. A Little History Much of the knowledge of the Black Death comes from chronicles We rely on works of artists for our visual pictures of the past Statistics are almost unknown during the Middle Ages; today compiling data is a vital part of our society

6. A Little History It was a common belief during the Middle Ages that the Black Plague was a punishment sent by God for the supposed wickedness and corruption of the times. Methods of preventing or treating the plague were often based on magic or the supernatural. Medieval doctors had no idea that a bacteria that lived on the fleas was the true cause of the plague

7. Black Death – a perfect storm Much of the mortality is explained by situational factors  Cooler climate conditions, excess of rain led to failed crop harvests and widespread hunger  Overcrowded medieval cities  Immunocompromised population living under stressful conditions –

8. A Little History Medieval cities were often crowded, dirty and unhealthy. Poor sanitation and a lack of personal cleanliness provided ideal ground for breeding disease 1/3 of the population died, leaving workers in short supply. Peasants began to realize their worth and demand fewer taxes and more rights  changed the world

9. Medieval Medicine Medievals believed that there were 4 humors in the human body. The balance of these 4 humors was essential for good health. Balance was achieved by diet, medicines and phlebotomy Blood – sanguine (social, pleasure) Phlegm – phlegmatic (relaxed, quiet) Yellow Bile – choleric (ambition) Black Bile – melancholy (thoughtful, sad)

10. Healing Herbal remedies were common Most treatment was done at home Given the medical uncertainty of the time, many medievals turned towards charms, special prayers or rituals Rural vs. city

11. The Culprits

12. The Famine of 1315- 1317  By 1300 Europeans were farming almost all the land they could cultivate.  A population crisis developed.  Climate changes in Europe produced three years of crop failures between 1315-17 because of excessive rain.  As many as 15% of the peasants in some English villages died.  One consequence of starvation & poverty was susceptibility to disease.

14. Symptoms  High fever  Swelling in the lymphs  Chills  Malaise  Muscle pain  Severe headache  Seizures 2-3 days pneumonic plague appears:  Severe cough  Frothy bloody sputum  Difficulty breathing

15. Septicemic Plague  Organ failure low blood pressure  Nausea, vomiting  Low blood pressure  Fever  Blood clotting problems  Abdominal pain Persons with the plague need immediate treatment, meaning within 24 hours of when the first symptoms occurred Antibiotics are used to treat the plague