浙江省诸暨市草塔中学高中英语 Unit 1 Great Scientists What do you know about cholera素材 新人教版必修5

浙江省诸暨市草塔中学高中英语 Unit 1 Great Scientists What do you know about cholera 素材 新人教版必修 5Cholera is a water-borne disease that is spread through polluted water and food. Cholera is an illness caused by the bacterium called Vibrio cholera (霍乱弧 菌 ). It produces an enterotoxin ( 肠 毒 素 ) that causes a painless, watery diarrhea (痢疾) that can quickly lead to severe dehydration (脱水) and death if treatment is not given. Vomiting （呕吐） also takes place in most patients. Most persons infected with cholera do not become ill, although the bacterium is present in their waste for 7-14 days. When this illness does strike, more than 90% of the time it is not severe and is difficult to tell from other types of diarrhea. Less than 10% of sick persons develop cholera with signs of moderate or severe dehydration.A person may get cholera by drinking water or eating food polluted with the cholera bacterium. The disease can spread rapidly in areas without the proper treatment of drinking water. The cholera bacterium may also live in the environment in dirty rivers and coastal waters. Shellfish eaten raw have been a source of cholera. Therefore, the disease is not likely to spread directly from one person to another.Cholera can be simply and successfully treated by immediate replacement of the fluid (液体) and salts lost through diarrhea. Patients can be treated by being given a mixture of sugar and salt to be mixed with water and drunk in large amounts. Antibiotics ( 抗 生 素 ) shorten the course and decrease the severity of the illness. Persons who develop severe diarrhea and vomiting in countries where cholera takes place should seek medical attention at once.To avoid cholera, we should eat well-cooked food instead of raw food.