Influenza: The Cutting Edge (IMAGE) Cold Spring Harbor Laboratory Press Caption Highly pathogenic avian influenza H7N9 viruses isolated from humans. The viral particles were examined by use of transmission electron microscopy after negative staining with uranyl acetate. Credit Image courtesy of Michiko Ujie and Masaki Imai, Institute of Medical Science, University of Tokyo Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.