A、They believe some plants in the jungles can cure the disease. B、They need to study animals that also get infected with the dis

A deadly infectious outbreak swept through a small city in Zaire Africa last spring, killing more than 100 people. The killer was a real virus that caused most victims to bleed to death. Although scientist rushed to control the outbreak, people in the U.S. wondered: “Could it attack here?” “We’re foolish to think it couldn’t come to our country,” say doctors, “the virus can be highly infectious. If you come into contact with a victim’s blood or other body fluids, you can get sick, too. All it takes is an infected person to start such a disease.” That’s what scientists believe happened in Zaire. The health-care workers who treated the first victims there soon fell ill, too. The problem was they had no protective equipment to prevent themselves from being infected. International rescue workers brought equipment to Zaire soon after the outbreak occurred. Now the disease appears to be under control. One big mystery is that no one knows where the virus comes from or where it will strike next. Some scientists say the virus lies inactive in the cell of some kind of plant, insect or other animal, then it somehow finds a way to infect humans. Scientists are now headed into jungles of Africa to find out where the virus lives. Once they find the virus they also hope to find ways to compel it.
Questions 33 to 35 are based on the passage you have just heard.
33. What happened to most of the victims of the disease mentioned in this passage?
34. Which of the following can be a medium to spread the disease?
35. Why are scientists going into the African jungles?