Research projects

Funding: BMBF, Conservation International, DFG, Operation Wallacea, Volkswagen-Stiftung, DAAD (PhD/reinvitation fellowship to BB, SR, RoR, AR RiR, AH) as well as to supervisors, Small Rufford Fund, private organisations

Project Details:
The Ankarafantsika National Park and the Mariarano forest contain different habitat types, including xerophytic forests, dry deciduous forests, semi-humid gallery forests along rivers or lake shores, coastal mangrove forests (Mariarano) and secondary vegetation formations that may develop after bushfires or selective wood extraction. This mosaic of habitat types offers many different ecological niches for lemurs and other forest dwelling organisms. Both forests are unique in northwestern Madagascar by harboring five endangered or critically endangered lemur species, one of which, the golden brown mouse lemur (Microcebus ravelobensis) was only recently described by our group in 1998. Moreover, the Ankarafantsika National Park comprises the largest remaining continuous patch of dry deciduous forest in northwestern Madagascar and is therefore of utmost importance for the longterm preservation of biodiversity in this biogeographic zone. Knowledge on the environmental flexibility of lemurs is still in its infancy, but urgently needed for conservation management. The aim of this longterm programme is to study the conservation biology of these lemur species, including their vulnerability towards diseases, at sites, for which we already have basic data. This knowledge will help to understand the environmental flexibility of species, how macrogeographic events such as climate change affect lemur?s life history and long-term survival and provide empirical data for long-term conservation management of lemurs in northwestern Madagascar.

Results:

e.g.

 

Klein, A.; Radespiel, U.; Springer, A.; Rakotondravony, R.; Strube, C. (2024): Temporal dynamics in gastrointestinal helminth infections of sympatric mouse lemur species (Microcebus murinus and Microcebus ravelobensis) in Northwestern Madagascar. International Journal for Parasitology: Parasites and Wildlife, 25, 100972. https://doi.org/10.1016/j.ijppaw.2024.100972.

 

Rasoloharijaona, S.; Randrianambinina, B.; Radespiel, U. (2024): Evidence for female dominance in the Milne-Edwards? Sportive lemur (Lepilemur edwardsi). American Journal of Primatology, e23658. https://doi.org/10.1002/ajp.23658.

 

Steffens, T.S.; Ramsay, M.S.; Andriatsitohaina, B.; Cosby, A.E.; Lehman, S.M.; Rakotondravony, R.; Razafitsalama, M.; Teixeira, H.; Radespiel, U. (2022): Shifting biogeographic patterns of Microcebus ravelobensis and M. murinus. Int. J. Prim., 43, 636-656. https://doi.org/10.1007/s10764-022-00304-z.

 

Wuesthoff, E.; Fuller T.K.; Sutherland, C.; Kamilar, J.M.; Ramanankirahina, R.; Rakotondravony, R.; Rouse, S.; Radespiel, U. (2021): Spatial partitioning of sympatric species of mouse lemurs across a mangrove-dry forest habitat gradient. J. Mammal. 102(5), 1266-1278. https://doi.org/10.1093/jmammal/gyab082.

 

Durden, L.A.; Kessler, S.E.; Radespiel, U.; Hasiniaina, A.F.; Stekolnikov, A.A.; Chalkowski, K.; Zohdy, S. (2021): Host associations of ectoparasites of the gray mouse lemur, Microcebus murinus, in northwestern Madagascar. J. of Parasitol. 107(1), 108-114. https://doi.org/10.1645/20-145.

Cooperation Partners:

Prof. Solofonirina Rasoloharijaona, University of Mahajanga, Madagascar

Prof. Blanchard Randrianambinina, University of Mahajanga, Madagascar

Dr. Romule Rakotondravony, University of Mahajanga, Madagascar

Dr. Rindra Ramanankirahina, University of Antananarivo, Madagascar

Dr. Hanta Razafindraibe, University of Antananarivo, Madagascar

Prof. Shawn Lehman, Toronto University, Canada

Prof. Hermann Behling, Georg-August-Universität Göttingen

Prof. Travis Steffens, University of Guelph, Canada; Planet Madagascar

Funding: DFG, 491.000 EUR

Project Details:
The aim of the project is to analyse host-parasite interactions between the Fasciola hepatica as parasite and dairy cows as host, taking into account the genome of both interaction partners. Until now, studies on endoparasite resistance have focused exclusively on the genome of the host or the parasite, without considering genotype-genotype interactions between these two players. Therefore, for the first time, interactions will be modelled considering bovine genotypes (Gh) and F. hepatica genotypes (Gp).

Results:

May, K., Hecker, A.S., Strube, C., Tong, Y., König, S. (2025) Genetic parameters and single-step genome-wide association analysis for trematode (Fasciola hepatica and Calicophoron / Paramphistomum spp.) infections in German dairy cows. Infection, Genetics and Evolution 128, 105712

 

Hecker, A.S., Raulf, M.-K., König, S., Knubben-Schweizer, G., Wenzel, C., May, K., Strube, C. (2024) In-herd prevalence of Fasciola hepatica and Calicophoron/Paramphistomum spp. infections in German dairy cows with comparison of two coproscopical methods and establishment of real-time pyrosequencing for rumen fluke species differentiation. Veterinary Parasitology 327, 110142

 

May, K., Hecker, A.S., König, S., Strube, C. (2024) Helminth co-infections have no additive detrimental impact on milk yield and milk quality compared to mono-infections in German dairy cows. Parasites & Vectors 17, 398

Cooperation Partners:

Dr. Dr. Katharina May, Justus-Liebig-Universität Gießen

Funding: BMBF, 122.004 EUR

Project Details:
Every year, about 750,000 people die from mosquito-borne diseases, including malaria, dengue fever, rift valley fever and chikungunya fever. The incidence of these diseases is expected to increase significantly over the next few decades, as the ranges of several mosquito species are expanding due to climate
change. Mosquitoes not only transmit diseases, but can also influence the severity of the diseases they transmit. It has been shown in experimental infections of animals, the transmission of arboviruses by mosquito bites compared to artificial infection can lead to an increase in the severity of the disease. In
addition, it is known that the saliva of insects and ticks can promote the progression of vector-borne diseases. The skin is the first organ to be exposed to an arbovirus infection, thus the initial infection events also significantly determine the course of the disease. It is therefore essential for many to investigate a natural infection of the skin via a mosquito bite. So far, this could only be achieved by in-vivo experiments (animal experiments). In this project, an alternative is to be developed by replacing animal models with human skin explants for ethical and physiological reasons. The challenge of this study will be to establish an assay in which mosquitoes can use the skin implants as potential hosts. The goal is a successful biting of the skin explants by mosquitoes. Exemplarily, in a second step the skin explants should be infected via bite of Rift Valley Fever Virus (RVFV) and/or Chikungunya Virus (CHIKV)-infected mosquitoes. If
successful, the project results will allow to choose from different models for future research questions.

Funding: Deutsche Forschungsgemeinschaft (DFG), 140.519 EUR

Project Details:
Mosquito-borne arboviruses are an increasing (re-)emerging threat for more than 781 million people in Africa (70% of the continental population) (Weetman et al., 2018). Aedes-borne yellow fever (YFV), dengue (DENV), chikungunya (CHIKV) and Zika virus (ZIKV) as well as Aedes- and Culex-borne Rift Valley fever (RVFV) virus infections have been documented from the African continent, but reports are sketchy. The absence of evidence-based risk maps for arbovirus infections prevents adequate planning of both public health and research resources. Although the main vectors Aedes aegypti, Aedes albopitus and Culex quinquefasciatus are prevalent in Central and West African countries (Kreamer et al., 2015); the distribution and the frequency of arboviral infections and outbreaks display a surprising heterogeneity between and within certain countries. Thus, we ask the key question: Do genetic variability and bionomic differences in local mosquito vector populations influence arbovirus occurrence across countries in West Africa?
Here we propose to assess the difference in human exposure to arboviruses (through an epidemiologic and serologic study) based on in-depth multi-national investigation on the vector?s biting behavior, virus surveillance, and the genetic structure of vector populations. We will conduct our study in three West and Central African countries (Benin, Gabon and Côte d?Ivoire) with different and specific epidemiological profiles. Benin (West Africa) will present a setting with low arboviral occurrence, Gabon (Central Africa) will represent a latent focus with high arboviral occurrence where no outbreaks have been reported since 2010, and Côte d?Ivoire (West Africa) will represent an active focus with high arboviral occurrence where ongoing outbreaks have been reported recently. In each country, the study will be conducted in already known arbovirus foci or potential arbovirus foci with arbovirus detection from either human, animal or mosquitoes. As arboviruses have been reported mainly in large African cities, the study will be conducted in the capital cities (and their surrounding towns) of every country to maximize the probability to observe an arboviral infection We will select three sites representing each rural, suburban or urban area to capture potential variability in arbovirus prevalence in connection with mosquito species diversity, and vector and human populations.
The outcomes will help directly to set up a sustainable network on arboviruses (termed EcoVir-network) which will work to contribute to improving the surveillance, prevention and control of arboviruses in Africa. Furthermore, we will build a well-trained new generation of young African scientists through our training program, who will in future contribute to arbovirus control in Africa.

Cooperation Partners:

Prof. Dr. Steffen Borrmann: Tübingen, Germany

Dr. Julien Zahouli Bi Zahouli: Abidjan; Côte d?Ivoire

Prof. Dr. Luc Salako Djogbenou: Abomey-Calavi, Benin

Dr. Gäel Darren Maganga: Franceville, Gabon

Prof. Dr. Ayola Akim Adegnika: Lambarene, Gabon

Prof. Dr. Jacques Mavoungou: Libreville, Gabon

Funding: DFG, 199.880 EUR

Project Details:
Proanthocyanidins are natural substances that have shorn to exhibit anthelmintic activity against various nematode species in vitro. However, it is unclear which molecular and cellular targets of the parasites are affected by proanthocyanidins. This question, as well as the effectiveness of the natural substances in parasitic infections, will be investigated in the current project.

Results:

François Ngnodandi Belga, F.N., Raulf, M.K., Spiegler, V., Liebau, E., Hensel, A. Strube, C., Ndjonka, D. (2024) In vivo anthelmintic activity of Combretum mucronatum Schumach & Thonn leaf extract against Haemonchus contortus in goats. Veterinary Parasitology 331, 110288

 

Belga, F.N., Waindok, P., Raulf, M.-K., Jato, J., Orman, E., Rehbein, S., Spiegler, V., Liebau, E., Hensel, A. Ndjonka, D., Strube, C. (2024) Phytochemical analysis and anthelmintic activity of Combretum mucronatum leaf extract against infective larvae of soil-transmitted helminths including ruminant gastrointestinal nematodes. Parasites & Vectors 17, 99

 

Jato, J., Waindok, P., Ngnodandi, F.N.B.F., Orman, E., Agyare, C., Bekoe E.O., Strube, C., Hensel, A., Liebau, E., Spiegler, V. (2023) Anthelmintic activities of extract and ellagitannins from Phyllanthus urinaria against Caenorhabditis elegans and zoonotic or animal parasitic nematodes. Planta Medica 89, 1215-1228

Cooperation Partners:

Prof. Dr. Andreas Hensel, Universität Münster

Prof. Dr. Eva Liebau, Universität Münster

Prof. Dr. Christian Agyare, Kwame Nkrumah University of Science and Technology (KNUST), Ghana

Prof. Dr. Dieudonne Ndjonka, University of Ngaoundéré, Kamerun

Dr. Emilia Oppong Bekoe, University of Ghana, Ghana

Funding: Intervet Deutschland GmbH, 124.000 EUR

Project Details:
Tick-borne diseases are gaining importance in both human and veterinary medicine. In the course of climate change, a change in tick activity is to be expected and will be investigated in this project. In addition, tick exposure of dogs and cats will be investigated and the prevalence of various pathogens in the ticks collected will be determined.

Results:

Probst, J., Springer, A., Topp, A.-K., Bröker, M., Williams, H., Dautel, H., Kahl, O., Strube, C. (2023) Winter activity of questing ticks (Ixodes ricinus and Dermacentor reticulatus) in Germany − Evidence from quasi-natural tick plots, field studies and a tick submission study.  Ticks and Tick-Borne Diseases 14, 102225

 

Probst, J., Springer, A., Strube, C. (2023) Year-round tick exposure of dogs and cats in Germany and Austria - results from a tick collection study. Parasites & Vectors 16, 70

Funding: DFG, 141.000 EUR

Project Details:
In this project, microbial changes in the pig intestine will be determined over the course of an Ascaris suum infection. In addition, samples will also be examined with regard to the metabolome. Furthermore, the question whether a single A. suum infection has the same effects as continuous exposure will be answered. Thus, the project aims at a comprehensive characterisation of the parasite-microbiome-host interactions in pig roundworm infections, the most significant helminthic parasitosis in pig farming.

Results:

Springer, A., Wagner, L., Koehler, S., Klinger, S., Breves, G., Brüggemann, D.A., Strube, C. (2022) Modulation of the porcine intestinal microbiota in the course of Ascaris suum infection. Parasite & Vectors 15, 433

Cooperation Partners:

Dr. D. Brüggemann, Max Rubner-Institut

Funding: Bundesministerium für Bildung und Forschung, Projektträger DLR, 217.069 EUR

Project Details:
In den letzten Jahren wurden neben Arboviren, die eine ernsthafte Bedrohung für die öffentliche Gesundheit darstellen, eng verwandte Viren aus der gleichen Virusfamilie beschrieben, welche durch ihre Insektenspezifität als nicht-humanpathogen oder wirbeltierpathogen angesehen werden. Diese Apathogenität gegenüber Mensch und Wirbeltier macht die insektenspezifischen Viren zu einem interessanten Modell für Arboviren, deren Evolution und Wechselwirkung mit Vektoren. Insektenviren haben weiterhin das Potential Arbovirus-Übertragungen zu hemmen und so direkt zu einer Verbesserung der öffentlichen Gesundheit beizutragen. In dieser Studie soll eine interdisziplinäre Herangehensweise, bestehend aus virologischer, verhaltensbiologischer und ökologischer Sicht, einen Fortschritt in der Vektorkontrolle erzielen. Hierbei soll die Interaktion von Culex pipiens molestus Mücken mit Insektenviren und insektiziden Wirkstoffen näher erforscht und die Anwendbarkeit einer solchen trilateralen Interaktion in der integrierten Stechmückenbekämpfung untersucht werden.

Results:

Heinig-Hartberger, M.; Hellhammer, F.; Zöller, D.D.J.A.; Dornbusch, S.; Bergmann, S.; Vocadlova, K.; Junglen, S.; Stern, M.; Lee, K.-Z.; Becker, S.C. (2023) Culex Y Virus: A Native Virus of Culex Species Characterized In Vivo. Viruses 15: 235. https://doi.org/10.3390/v15010235

https://doi.org/10.3390/v15010235

Cooperation Partners:

Dr. Kwang-Zin Lee, Frauenhofer IME

Funding: Elanco, 20.000 EUR

Project Details:
In recent years, the incidence of Tick-borne encephalitis (TBE) has increased in areas that are not considered official risk areas. In Germany, most of these areas are located in southern Germany, however, in the beginning of 2019, the National Institute of Public Health (Robert-Koch-Institut) declared a district in the Northern Germ federal state Lower Saxony as official risk area. In order to better assess the TBE risk for humans and animals in Lower Saxony and to obtain information on the localisation of natural foci, sera from livestock, pet and wild animals from Lower Saxony will be tested for TBE antibodies. Serum collection will particularly include districts in which human TBE cases have occurred.

Cooperation Partners:

Dr. U. Nagel-Kohl, LAVES, Hannover

Prof. Dr. Gerhard Dobler, Nationales Konsiliarlabor für FSME, München

Funding: Pfizer, 170.000 EUR

Project Details:
This first Germany-wide field study will create a dataset with monthly tick densities over a 3-year at selected sites in Germany. The data collected will serve as input data for a statistical model to predict tick density.

Cooperation Partners:

Dr. O. Kahl, tick-radar GmbH

Prof. Dr. U. Mackenstedt, Universität Hohenheim

Prof. Dr. M. Pfeffer, Universität Leipzig