Amur Tigers Boris and Svetlaya (IMAGE) Proceedings of the National Academy of Sciences Caption Samples collected from Amur tigers including�Boris and Svetlaya (pictured) enabled the researchers to assess the population's exposure to canine distemper virus Credit Image credit: Wildlife Conservation Society 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.