单选题 Influenza has been with us a long time. According to some Greek writers 1 medical history, the outbreak of 412 B. C. was of influenza. The same has been suggested of the sickness 2 swept through the Greek army attacking Syracuse in 395 B.C. Flu is a disease that moves most quickly among people living in 3 conditions, hence, it is likely to attack armies.
4 the nineteenth century there were five widespread outbreaks of influenza. The last of the five 5 in 1889 and marked the beginning of the story of influenza in our time. 6 the recent outbreak, it started in Asia.
For more than forty years before that outbreak, influenza had steadily 7 and was believed to be dying out. A new group of outbreaks was 8 by the great outbreak of 1889-1890 and for the next quarter of a century influenza remains a constant threat.
In April 918 flu broke among American troops stationed in France. It quickly spread through all the 9 but caused relatively few deaths. Four months later, however, a second outbreak started which 10 to be a killer. It killed not only the old and already sick but also healthy young adults. It went through every country in the world. It brought the life of whole countries to stop, food supplies stopped and work loss was very great. It is thus clear that influenza is a terrible infection that we have to pay more attention to.