東京慈恵会医科大学
医学部 英語
2026年度 解答・解説

Some of the most important discoveries in medicine were the result of an A, fortunate mistake by a single researcher. Many others, however, came from the slow work of many people, each adding a little to what had been learned before. Such was the case with one of the great public health successes of the 19th century, the discovery of how tidewater fever spreads.

Tidewater fever is an infection that causes a high temperature, pain in the joints, and a deep tiredness that can last for weeks. Before the 1880s, doctors in the port town of Carrow believed that it was caused by bad air rising from the harbor mud, because every year the outbreaks began in midsummer, when the tide flats dried out in the heat. The standard advice was to keep the windows shut at night. This advice could only B residents' discomfort a little, and the disease returned every summer.

The first step towards the truth came in 1884, when a physician named Anselm Kroll noticed that sailors sleeping on ships anchored far from the shore rarely became ill, while fishermen living by the water often did. He collected water from the tide flats and found tiny living things in it. When he injected the water into guinea pigs, however, they died within hours of other causes, so the water could not be used to show anything about the disease.

At that time, the part played by insects in spreading disease was hardly understood. Ten years earlier, a naturalist named Ines Varga had described a small biting fly that lived only in the salt marshes around Carrow. Large numbers of the flies were found C in the mud of the marsh during the day, and they came out to feed at dusk. Varga suggested in her report that the fly might carry a disease, but few doctors read it.

Kroll came across her report by chance and wondered whether the fly was the missing link. He asked a young colleague, Tobias Lind, to make fine nets and hang them over the beds of families in the harbor district. In houses where the nets were used, no new cases appeared that summer, while neighboring houses without nets suffered as before. The fly, not the air, was spreading the fever.

In 1891, the city council gave Kroll a gold medal for his work, but Varga's name did not appear on the certificate. Kroll was embarrassed, so he announced that he would give half of the prize money to her. Lind D by announcing that he would share his own small reward with the nurses who had hung the nets. So, ironically, because the doctors were so eager to be fair to one another, the credit for the discovery ended up spread among many more people than anyone had expected.

By 1895, the city had begun producing enough E netting for every home in the harbor district, and the number of cases F sharply within a few years. Later improvements in drainage and in the design of houses made the protection even stronger. Thus, the discovery turned a yearly threat into a disease that most people in Carrow no longer feared.

Our expectations shape not only what we notice but also how we feel. Can the mere expectation of harm really make a person ill? Many doctors now say yes. Dr. Lucia Ferreira trained in medicine in 1962 and spent decades working in small hospitals in the north of the country. In her early years, she accepted without question the standard view that every sickness had a physical cause, and that finding and treating that cause would A.

However, her experience with many patients slowly persuaded her that this view was too narrow. Again and again she met people who became sick because they expected to be sick, even though nothing was physically wrong with them. She recalls one man who was told that his headaches were the first sign of a serious brain disease. He lost weight, stopped sleeping, and grew steadily weaker; yet when he was examined later, it turned out that his doctors B: there was no disease at all. His fear alone had been making him ill.

She tells an even stranger story about a farmer named Walter Penn, a patient of her teacher, Dr. Harold Quill. In the autumn of 1951, Quill was asked to visit the farm of a fifty-year-old man who had not eaten for days and could barely stand. Illness was suspected, but every test failed to C. At last, when Penn seemed close to death, his daughter told Quill that, a week earlier, an old woman in the village, who was said to have special powers, had pointed at him and said, "Before the harvest is over, you will be gone." Walter D and had not eaten since.

Quill thought carefully about what to do. The next morning he asked the whole family to come to the bedroom, and then he spoke in the most serious voice he could manage. He said that he had visited the old woman during the night and had made her admit that she had only wanted to frighten the farmer, and that the curse had never been real. "But to be safe," he added, "I will remove what she has put inside you." He sent for his assistant, who E a clear liquid into Penn's arm; it was, in fact, only a mild medicine to settle the stomach.

Within the hour, Penn was sitting up. By evening he was asking for soup, and the next day he walked to the barn by himself. He F for another fifteen years. "It is very clear," writes Ferreira, "that Walter believed, in the deepest part of his mind, that his days were numbered." Words alone had been enough to bring him to the edge of death, and in the end, words alone had also been able to X.

Almost all of you have probably had this experience: a song that sounded strange the first time you heard it slowly becomes one of your favorites. For example, you might hear a new song A in the shops and cafés you visit during one week. After a few days, you find yourself humming it, even though you did not like it at first. This is known as the mere-exposure effect. Several reasons can be given to explain this phenomenon.

The first reason is familiarity. Your brain has to deal with an enormous amount of new information every day, and unfamiliar things require extra effort. Your brain, therefore, is happy to ignore anything that it does not B harmful. When you meet something for the second or third time without any bad result, your brain relaxes and marks it as safe, and this feeling of safety slowly turns into a feeling of liking.

The other reason is ease of processing. Things you have seen or heard before are processed more quickly, and this smoothness feels pleasant. You may believe that you like something for its own qualities, but your brain is often simply enjoying how easy it is to recognize. In the same way, people tend to doubt or ignore information that C their existing preferences.

The mere-exposure effect is commonly used by advertisers. By showing you the name and the face of a product again and again, they make sure that you recognize it the next time you go shopping. It also makes that product seem to be the safest or most reliable one D.

The effect is not just an amusing phenomenon but can have various effects on your mind. On the positive side, it can help you with learning a language. You might see a new word several times in different books, and the repeated exposure makes the word feel familiar, so you can remember it more easily.

On the negative side, though, the effect can influence how you make decisions. When you have met a treatment many times, you tend to trust it and to overlook other possibilities. For doctors, especially, this can be dangerous because it might lead to the continued use of an old treatment when a better one exists. A doctor may be more likely to keep using a familiar drug even if the evidence for a new drug is E to change the choice.