Reading

1. Reading • Pre-reading • Reading • Post-reading

2. Pre-reading • What do you know about infectious diseases? • Do you know how to prove a new scientific research? Discuss in small groups the stages in examining a new scientific idea. What order should you put them in? ⑦ Make a conclusion Think of a method Collect results Make up a question Find a problem Analyse the results Repeat if necessary ③ ④ ② ① ⑤ ⑥

3. Reading • Supply the following words with detail. John Snow Cholera Two theories on cholera The correct theory Steps of his research

4. Group Discussion • Cholera is a 19th century disease. What disease do you think is similar to cholera today? • Do you think John Snow would have solved this problem without the map? • What should you do if you're travelling to a country that has a cholera outbreak according to Snow’s theory?

5. What should you do if you're travelling to a country that has a cholera outbreak? • Drink only water that you have boiled or treated with chlorine or iodine. Other safe drinks include tea or coffee made with boiled water and carbonated, bottled beverages with no ice. • Eat only food that's been thoroughly cooked and is still hot, or fruit that you've peeled yourself. • Avoid undercooked or raw fish and shellfish. • Avoid raw salads and vegetables. • Avoid food and drinks from street vendors. "Boil it, cook it, peel it, or forget it." TIPS

6. The End

7. John Snow (1813-1858)

8. John Snow was born in York on March 15th, 1813, the oldest of nine children. York London His father worked as a laborer. While poor, his parents were determined to give their children whatever educational opportunities they could afford. He was educated at a private school in his native city until the age of fourteen, when he was apprenticed(当学徒) to William Hardcastle, a surgeon(外科医生) living at Newcastle-on-Tyne.

9. 1836 37 38 39 40 41 42 43 44 1845 After serving for a short time as a surgeon and unqualified assistant during the cholera epidemic of 1831-2, he became in October 1836 a student at the Hunterian School of medicine in Great Windmill Street, London. He began to attend the medical practice at the Westminster Hospital in the following October, He graduated M.D. of the University of London on 20 Dec. 1844, and in 1850 he was admitted a licentiate of the Royal College of Physicians.

10. Dr. Snow was also a prominent anesthesiologist(麻醉师) He designed a chloroform inhaler(氯仿吸入器), described in his book, On Chloroform and other Anesthetics, published in 1858. What else was he famous for?

11. What is Cholera? • Cholera is the illness caused by a bacterium called Vibria cholerae. It infects people‘s intestines(肠), causing diarrhea(腹泻), vomiting and leg cramps. The most common cause of cholera is by someone eating food or drinking water that has been contaminated with the bacteria. • After a disaster, this is a very real danger, since regular, clean water and food supplies are often unavailable. The disease can be spread even further by infected people using already dirty water sources to clean themselves or dispose of waste.

12. Cholera can be mild or even without symptoms, a severe case can lead to death without immediate treatment. The diarrhea and vomiting brought on by the infection quickly leaves the body without enough fluid. The following dehydration(脱水) and shock can kill a person within hours.

13. The spread of cholera Previous cholera epidemic in Great Britain in 1831-32 Great Britain London Death of first cholera case in London during the 1848-49 epidemic Germany

14. death "…I found that nearly all the deaths had taken place within a short distance of the pump." Snow on Cholera

15. Snow suspected contamination of pump water. Small, white, flocculent particles

16. Steps of his research Cholera epidemic • Find a problem • Make up a question • Think of a method • Collect results • Analyse the results • Repeat if necessary • Make a conclusion How did cholera kill people? Gather information Mark on the dead people on the map the dead people Many of the deaths were near the water pump. Two other deaths in another part Cholera was spread by germs instead of a cloud of gas