Avian Influenza A H5N1 Viruses (IMAGE) American Society for Microbiology Caption This is a colorized transmission electron micrograph of Avian influenza A H5N1 viruses. Credit Wikipedia Usage Restrictions Attribution 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.