Francisella tularensis and tularemia

The bacterium today known as Francisella tularensis was first identified 99 years ago and, since then, much research has been devoted to study it and the resulting disease, tularemia. F. tularensis became the focus of an intense research effort during the first half of the 20th century, in particularly in the United States and Soviet Union, since the disease was fairly common. Due to its high infectivity, ease of spread, and severity of the resulting disease, it was one of the agents given the highest priority in the biological weapon programs of the United States and Soviet Union. After termination of these programs in the 1960s, the interest in F. tularensis diminished significantly, but after several decades of little attention, the last decade has led to resurgence in the research on F. tularensis. In 2003, the Science magazine phrased it as follows: “an obscure weapon of the cold war edges into the limelight”. There were multiple reasons for this resurgence, one of which was an increase in the number of tularemia cases in several European countries and, moreover, the intense research effort on potential bioterrorist agents in the US post 9/11. Thereby, the number of annual publications on F. tularensis has tripled in 10 years, and many new research groups, in particular American, have entered the field. This has led to very rapid development of state-of-the-art research tools, and fast progress in the understanding of F. tularensis. A proof of the rapid progress was the publication of a comprehensive volume on Francisella and tularemia in 2007. Although only four years ago, the rapid pace of the research has led to many new discoveries since then and, to this end, we now present a collection of articles from leading scientists on the up-to-date knowledge regarding F. tularensis. The articles cover important areas such as molecular research tools, experimental models, genomics, virulence mechanisms, manipulation and subversion of host responses, host immune responses, and the ecology of F. tularensis.