and populations from Central Europe are susceptible to West Nile virus infection.

West Nile virus (WNV), a with an avian primary host, is already widespread in Europe and might also pose an infection risk to Germany, should competent mosquito vectors be present. Therefore, we analysed the ability of WNV to infect German mosquitoes with special emphasis on field collected specimens of and biotype . We collected egg rafts of mosquitoes over two subsequent seasons at two geographically distinct sampling areas in Germany and differentiated the samples by molecular methods. Adult females, reared from the various egg rafts, were challenged with WNV by feeding of artificial blood meals. WNV infection was confirmed by real-time RT-PCR and virus titration. The results showed that field collected . biotype and . mosquitoes native to Germany are susceptible to WNV infection at 25 °C as well as 18 °C incubation temperature. . mosquitoes, which have not been established as WNV vector so far, were the most permissive species tested with maximum infection rates of 96% at 25 °C. Furthermore, a disseminating infection was found in up to 94% of tested . biotype and 100% of . . Considering geographical variation of susceptibility, . biotype mosquitoes from Southern Germany were more susceptible to WNV infection than corresponding populations from Northern Germany. All in all, we observed high infection and dissemination rates even at a low average ambient temperature of 18 °C. The high susceptibility of German populations for WNV indicates that an enzootic transmission cycle in Germany could be possible.