U. S. and Russian government officials say it is essential they keep some smallpox alive in case a future biological threat demands more tests with the virus.
美国和俄罗斯的官方表示，留存一些天花病毒以进行更多的测试，这对未来应对生物威胁是非常必要的。
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A computer virus that logs keystrokes has infected computers used in Nevada to remotely pilot U. s. drones over Afghanistan and other war zones, Wired reports.
Meanwhile, Novavax will be begin human tests of its seasonal influenza vaccine, using virus-like particles, in the fall. Currently all U. S. flu vaccines are egg-based.