A What Is A Hookworm Infection (感染)?
Hookworm is an infection of one of two different 7 to 13 mm long roundworms. Heavy infection with hookworm can create serious health problems for newborns, children, pregnant women, and persons who are malnourished. Approximately one-quarter of the world’s population is infected with hookworm.
B Where are hookworms commonly found?
One of the most common species, Ancylostoma Duodenale, is found in southern Europe, northern Africa, northern Asia, and parts of South America. A second species, Necator Americanus, was widespread in the southeastern United States early in this century. The Rockefeller Sanitary Commission was founded in response, and hookworm infection has been largely controlled.
C How do I get a hookworm infection?
You can become infected by direct contact with contaminated (污染的) soil, generally through walking barefoot, or accidentally swallowing contaminated soil.
Hookworms have a complex life cycle that begins and ends in the small intestine (肠道). Hookworm eggs require warm, moist, shaded soil to hatch into larvae (幼虫). These barely visible larvae enter the skin (often through bare feet), are carried to the lungs, go through the breathing tract to the mouth, are swallowed, and eventually reach the small intestine. This journey takes about a week. In the small intestine, the larvae develop into half-inch-long worms, attach themselves to the intestinal wall, and suck blood. The adult worms produce thousands of eggs. These eggs are passed in the human waste. If the eggs contaminate soil and conditions are right, they will hatch, molt, and develop into infective larvae again after 5 to 10 days.
D Who is at risk?
People who have direct contact with soil that contains human feces (粪便) in areas where hookworm is common are at high risk of infection. Children—because they play in dirt and often go barefoot—are at high risk. Since transmission of hookworm infection requires development of the larvae in soil, hookworm cannot be spread person to person. Contact among children in institutional or child care settings should not increase the risk of infection.
E _______________
In countries where hookworm is common and re-infection is likely, light infections are often not treated. In the United States, hookworm infections are generally treated for 1-3 days with medication prescribed (开药方) by your health care provider. The drugs are effective and appear to have few side effects. For children under the age of 2, the decision to treat should be made by their health care provider.
59. We can guess that the passage is intended for __________.
A. doctors B. scientists C. medical students D. common readers
60. We can imply that the Rockefeller Sanitary Commission in the second paragraph is_______.
A. a centre for information about hookworm infection in the United States
B. an organization for preventing and treating the hookworm infection
C. an educational organization in the United States in the 1950s
D. an organization which identifies the hookworm all over the world
61. The best heading for Part E should be ________.
A. What are the symptoms of hookworm?
B. How can I prevent hookworm?
C. What should I do if I think I have a hookworm infection?
D. What is the treatment for hookworm?
62. Which of the following statements about the life cycle of hookworms is right according to the passage?
A. Hookworm eggs develop into hookworm larvae in the small intestine.
B. Hookworm larvae feed on human’s blood in the intestine walls.
C. Hookworm eggs will become larvae in warm, moist, shaded soil.
D. Hookworm larvae will become hookworm eggs in human waste.