Biology subjects

Sauter-Louis, C.

Publications and source records attributed to Sauter-Louis, C..

3 recordsLinked to original sources

bioRxiv2026

Buffaloed in Brandenburg: Germany's first Brush with Foot-and-Mouth Disease after four Decades of Freedom

Foot-and-mouth disease (FMD) virus is one of the most feared and most consequential pathogens of livestock worldwide. It can be spread rapidly by the transboundary movement of animals, animal products and byproducts. In January 2025, Germany detected its first FMD outbreak since 1988 in extensively reared water buffalo on a small farm in the state of Brandenburg, directly outside Berlin, the federal capital. Immediate control measures including a standstill for movements of susceptible animals and pre-emptive culling were implemented by the veterinary authorities. Whole-genome sequencing identified the virus as serotype O, topotype ME-SA, lineage SA-2018 and revealed extensive recombination, but cross-neutralization assays suggested good heterologous protection by an O/PanAsia-2 vaccine strain. Epidemiological back-calculation placed the time of virus introduction in late December 2024. Although the entry route remains unresolved, human-associated introduction is most likely. Network analysis revealed minimal farm connectivity, and simulations predicted low potential for onward transmission, which is consistent with the outbreak being ultimately restricted to a single herd. This event underscores the constant and unpredictable risk of introduction of the virus. Early detection through increased awareness and comprehensive differential diagnostics as well as the international collaboration of veterinary services, laboratories and experts are essential in the face of the global presence of FMD.

microbiology↗

bioRxiv2024

Circulation of West Nile Virus and Usutu Virus in Birds in Germany, 2021 and 2022.

BackgroundUsutu virus (USUV) and West Nile virus (WNV) are zoonotic arthropod-borne orthoflaviviruses. The enzootic transmission cycles of both include Culex mosquitoes as vectors and birds as amplifying hosts. For more than ten years, these viruses have been monitored in birds in Germany by a multidisciplinary network. While USUV is present nationwide, WNV used to be restricted to the central-east. MethodsIn 2021 and 2022, over 2300 live bird blood samples and organs from over 3000 deceased birds were subjected to molecular and serological analysis regarding presence of WNV and USUV. The samples were collected at sites all over Germany. ResultsCirculation of both viruses increased in 2022. For USUV, the nationwide presence of lineages Africa 3 and Europe 3 reported in previous years was confirmed. Lineage Europe 2, formerly restricted to the German east, was able to expand westward. Nonetheless, USUV neutralizing antibody (nAb) detection rates remained low (< 9%). 2021 and 2022 were characterized by stable enzootic circulation of WNV lineage 2, dominated by one previously identified subcluster (95% of generated sequences). In 2022, more than 20% of birds in the endemic region in eastern Germany carried nAb against WNV. Serological data also indicate expanding WNV circulation west and south of the known hotspots in Germany. ConclusionsUSUV circulates enzootically nationwide. Emergence of WNV at several new locations in Germany with a potential increase in human infections may be imminent. In this context, wild bird monitoring serves as a capable early-warning system in a One Health setting.

microbiology↗

bioRxiv2022

African swine fever virus - variants on the rise

African swine fever virus (ASFV), a large and complex DNA-virus circulating between soft ticks and indigenous suids in sub-Saharan Africa, has made its way into swine populations from Europe to Asia. This virus, causing a severe haemorrhagic disease (African swine fever) with very high lethality rates in wild boar and domestic pigs, has demonstrated a remarkably high genetic stability for over 10 years. Consequently, analyses into virus evolution and molecular epidemiology often struggled to provide the genetic basis to trace outbreaks while few resources have been dedicated to genomic surveillance on whole-genome level. During its recent incursion into Germany in 2020, ASFV has unexpectedly diverged into five clearly distinguishable linages with at least ten different variants characterized by high-impact mutations never identified before. Noticeably, all new variants share a frameshift mutation in the 3 end of the DNA polymerase PolX gene O174L, suggesting a causative role as possible mutator gene. Although epidemiological modelling supported the influence of increased mutation rates, it remains unknown how fast virus evolution might progress under these circumstances. Moreover, a tailored Sanger sequencing approach allowed us, for the first time, to trace variants with genomic epidemiology to regional clusters. In conclusion, our findings suggest that this new factor has the potential to dramatically influence the course of the ASFV pandemic with unknown outcome. Therefore, our work highlights the importance of genomic surveillance of ASFV on whole-genome level, the need for high-quality sequences and calls for a closer monitoring of future phenotypic changes of ASFV.

genomics↗