Table of contents

March 2011 - Volume 66 - 3

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H1N1 flu virus particle. Computer artwork of an H1N1 influenza A (flu) virus particle (virion). In the particle's lipid envelope (purple) are two types of protein spike, haemagglutinin (H) and neuraminidase (N), which determine the strain of virus. These are used for recognising and binding to the host cell. PASIEKA / SCIENCE PHOTO LIBRARY.