HIV-Infected H9 T Cell (IMAGE) PLOS Caption Gut microbiome may contribute to HIV transmission in high-risk men. Credit NIAID, Flickr CCBY2.0 Usage Restrictions All figures and photographic images will be published under a Creative Commons Attribution License (CCAL), which allows them to be freely used, distributed, and built upon as long as proper attribution is given. 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.