<I>Treponema pallidum</I> (IMAGE) University of Zurich Caption Immunofluorescence photomicrograph of Treponema bacteria in human tissue. Credit Steven J. Norris, UTHealth McGovern Medical School, Houston/USA 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.