Now, U.S. researchers have identified a new way to treat people infected with tuberculosis (肺结核)before they get sick.

Tuberculosis is one of the world’s most ______ health threats.The World Health Organization says tuberculosis kills nearly two million people each year. Another two billion are ______: they are infected, but don’t have symptoms of the disease. Those at highest risk can take medicine, but Vanderbilt University researcher Timothy Sterling says not everyone ______ with the treatment, which is a daily dose of isoniazid(异烟肼，抗结核药)for nine months. So although the medication is highly effective if people take all of their medication, many people do not take all their medication and therefore the effectiveness of the treatment plan is______. As a(n) ______, Sterling and his colleagues ______ isoniazid with another drug, rifapentine(利福喷汀).The combination was taken weekly, not daily, for just three months. And the results of this study showed that the new treatment plan ---- the three months of isoniazid and rifapentine---- was as effective as the nine–month isoniazid treatment plan.______, the short-course, three-month treatment plan had higher treatment completion rates and was also well ______.

There was some other difference. The two-drug, combination treatment was administered as directly ______ therapy. That means the patients took their medicine in the presence of a health care worker, to ensure that they followed the treatment plan. This was a large study, involving 7,500 participants in North America, Spain, and Brazil. Sterling ______ that most of the people in this study were HIV-negative. The results might be ______for HIV-positive people. A recent study in South Africa indicated that the combination therapy works well in people infected with HIV as well as tuberculosis, but the study was too small to be______.

Timothy Sterling’s research, published in The New England Journal of Medicine, has been ______ by the U.S. Centers for Disease Control and Prevention, the CDC. The government health agency recommends the 12-dose weekly combination treatment as an equal alternative to the 270–dose daily treatment plan that has been the______therapy. But because of possible ______ issues, the CDC still recommends the daily treatment plan for HIV–positive patients who are taking antiretroviral drugs or women who are pregnant. Also because of a lack of data, the CDC says children under age 12 should stay with the nine-month daily treatment.