Those studying the disease needed to know where wild birds were migrating and whether they carried the virus from its incubation points in large duck and chicken farms.
要回答这些问题不仅需要弄清野生鸟类的迁徙途径，还需要弄清它们是否携带了潜伏在大型养殖场中的病毒。
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Monitoring duck populations for the H5N1 virus and tracking rice farming by satellite are the optimal ways to predict an outbreak's distribution, the researchers said.