Tick (IMAGE) University of Texas at San Antonio Caption The bacterium, Francisella tularensis, is highly infectious, even fatal, when introduced in the lungs. It has been found in infected animals, such as rabbits, as well as in insects and ticks. Credit UTSA Courtesy Photo 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.