11. Blood tests specific for Y . pestis showed that five participants in the study were infected. 12. Both are caused by the bacterium Yersinia pestis and are easily treated with antibiotics like tetracycline. 13. Caused by a bacterium, Yersinia pestis 14. An even deadlier form, pneumonic plague, develops when a person inhales Y . pestis . 15. The virus is called Yersinia pestis . 16. But scientists warn that plague probably is triggered by a particularly crafty bacterium, Yersinia pestis . 17. Additionally, Pulicidae transmit " Yersinia pestis ", the bacteria responsible for plague. 18. As civilization concentrated in crowded, dirty cities, Y . pestis became hardier and more infectious. 19. Bubonic plague is an infectious disease of animals and humans caused by a bacterium named Yersinia pestis . 20. A variety of alternatives to the " Y . pestis " have been put forward.
