Research article

Re-emergence of tularemia in Germany: Presence of Francisella tularensis in different rodent species in endemic areas

Philipp Kaysser¹ , Erik Seibold¹ , Kerstin Mätz-Rensing² , Martin Pfeffer¹ , Sandra Essbauer¹ and Wolf D Splettstoesser^1,3

¹Bundeswehr Institute of Microbiology, Neuherbergstrasse 11, D-80937 Munich, Germany

²German Primate Center, Kellnerweg 4, D-37077 Göttingen, Germany

³Institute of Medical Microbiology, Virology and Hygiene, University Hospital Rostock, Schillingallee 70, D-18057 Rostock, Germany

author email corresponding author email

BMC Infectious Diseases 2008, 8:157doi:10.1186/1471-2334-8-157

Published:	17 November 2008

Abstract

Background

Tularemia re-emerged in Germany starting in 2004 (with 39 human cases from 2004 to 2007) after over 40 years of only sporadic human infections. The reasons for this rise in case numbers are unknown as is the possible reservoir of the etiologic agent Francisella (F.) tularensis. No systematic study on the reservoir situation of F. tularensis has been published for Germany so far.

Methods

We investigated three areas six to ten months after the initial tularemia outbreaks for the presence of F. tularensis among small mammals, ticks/fleas and water. The investigations consisted of animal live-trapping, serologic testing, screening by real-time-PCR and cultivation.

Results

A total of 386 small mammals were trapped. F. tularensis was detected in five different rodent species with carrier rates of 2.04, 6.94 and 10.87% per trapping area. None of the ticks or fleas (n = 432) tested positive for F. tularensis. We were able to demonstrate F. tularensis-specific DNA in one of 28 water samples taken in one of the outbreak areas.

Conclusion

The findings of our study stress the need for long-term surveillance of natural foci in order to get a better understanding of the reasons for the temporal and spatial patterns of tularemia in Germany.