Passage1
Do who choose to go on exotic，far-flung holidays deserve free health advice before they travel？And even if they pay，who ensures that they get good，up-to-date information？Who，for that matter，should collect that information in the first place？For a variety of reasons，travel medicine in Britain is a responsibility nobody wants.As a result，many travellers go abroad prepared to avoid serious disease.
Why is travel medicine so unloved？Partly there's an identity problem. Because it takes an interest in anything that impinges on the health of travelers ，this emerging medical specialism invariably cuts across the traditional disciplines. It delves into everything from seasickness，jet lag and the hazards of camels to malaria and plague. But travel medicine has a more serious obstacle to overcome. Travel clinics are meant to tell people how to avoid ending up dead or in a hospital when they come home，but it is notoriously difficult to get anybody pay out money for keeping people healthy.
Travel medicine has also been colonized by commercial interests; the vast majority of travel clinics in Britain are run by airlines or travel companies. And while travel concerns are happy to sell profitable injections, they may be less keen to spread bad news about travellers' diarrhea in Turkey, or to take time to spell out preventive measures travellers could take."The NHS finds it difficult to define travellers' health,"says Ron Behrens,"the only NHS consultant in travel and director of the travel clinic of the Hospital for Tropical Diseases in London."Should it come within the NHS or should it be paid for?"It's Gary area, and opinion is spilt. No one seems to have any responsibility for defining its role,"he says.
To compound its low status in the medical hierarchy, travel medicine has to rely on statistics that are patchy at best. In most cases we just don't know how many Britons contract diseases when abroad. And even if a disease linked to travel there is rarely any information about where those afflicted went, what they are, how they behaved, or which vaccinations they had. This shortage of hard facts and figures makes it difficult to give detailed advice to people, information that might even save their lives.
A recent leader in British Medical Journal argued."Travel medicine will emerge as credible disciplines only if the risks encountered by travellers and the relative benefits of public health interventions are well defined in terms of their relative occurrence, distribution and control."Exactly how much money is wasted by poor travel advice. The real figure is anybody's guess, but it could easily run into millions. Behrens gives one example. Britain spends more than £ 1 million each year just on cholera vaccines that often don't work and so give people a false sense of security."Information on the prevention and treatment of all forms of diarrhea would be a better priority," he says.
The phrase "delves into" in Paragraph 2 can be replaced by_______.
into a mouse's brain. But now Wendy Ingram, a graduate student at the University of California, Berkeley, has challenged this common sense. She has found a way to "cure" mice of their inborn fear of cats by infecting them with a parasite, reported the science journal Nature. The parasite, called Toxoplasma gondii, might sound unfamiliar to you, but the shocking fact is that up to one-third of people around the world are infected by it. This parasite can cause different diseases among humans, especially pregnant women-it is linked to blindness and the death of unborn babies. However, the parasite's effects on mice are unique. Ingram and her team measured how mice reacted to a cat's urine (尿) before and after it was infected by the parasite. They noted that normal mice stayed far away from the urine while mice that were infected with the parasite walked freely around the test area. But that's not all. The parasite was found to be more powerful than originally thought-even after researchers cured the mice of the infection. They no longer reacted with fear to a cat's smell, which could indicate that the infection has caused a permanent change in mice's brains. Why does a parasite change a mouse's brain instead of making it sick like it does to humans? The answer lies in evolution. "It's exciting scary to know how a parasite can manipulate a mouse's brain this way," Ingram said. But she also finds it inspiring. "Typically if you have a bacterial infection, you go to a doctor and take antibiotics and the infection is cleared and you expect all the symptoms to also go away." She said, but this study has proven that wrong. "This may have huge implications for infectious disease medicine."
