Scientists around the world are racing to learn how to rapidly diagnose, treat and stop th

e spread of a new, deadly disease. SARS—Severe Acute Respiratory Syndrome—was 【31】______ for the first time in February 2003 in Hanoi, 【32】______ since then has infected more than 1,600 people in 15 countries, killing 63. At this 【33】______ , there are more questions than answers surrounding the disease. Symptoms start 【34】______ a fever over 100.4 degrees F, chills, headache or body 【35】______. Within a week, the patient has a dry cough, which might 【36】______ to shortness of breath. In 10% to 20% of cases, patients require 【37】______ ventilation to breathe. About 3.5% die from the disease. Symptoms 【38】______ begin in two to seven days, but some reports suggest it 【39】______ take as long as 10 days. Scientists are close to 【40】______ a lab test to diagnose SARS. In the meantime, it is diagnosed by its symptoms. There is no evidence 【41】______ antibiotics or anti-viral medicines help, 【42】______ doctors can offer only supportive care. Patients with SARS are kept in isolation to reduce the risk of 【43】______ . Scientists aren't sure yet, but some researchers think it's a 【44】______ discovered corona virus, the family of viruses that cause some common colds. Most cases appear to have been passed 【45】______ droplets expelled when infected patients cough or sneeze. Family members of infected people and medical workers who care 【46】______ them have been most likely to 【47】______ the illness. But recent developments in Hong Kong suggest that the 【48】______ might spread through air, or that the virus might 【49】______ for two to three hours on doorknobs or other 【50】______ . Health experts say it is unlikely, though, that sharing an elevator briefly with an infected person would be enough to pass the virus.

A．detected

B．caught

C．disclosed

D．revealed