Influenza A H5N1 Immigration Is Filtered Out at Some International Borders

• Robert G. Wallace ,

  *To whom correspondence should be addressed. E-mail: rwallace@uci.edu

  Affiliation Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, California, United States of America

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• Walter M. Fitch

  Affiliation Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, California, United States of America

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