{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,12]],"date-time":"2026-10-12T12:08:13Z","timestamp":1791806893911,"version":"4.3.4"},"reference-count":47,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,12,9]],"date-time":"2021-12-09T00:00:00Z","timestamp":1639008000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Federal Office for Agriculture and Food (BLE)","award":["2819104615"],"award-info":[{"award-number":["2819104615"]}]},{"name":"German Federal Office for Agriculture and Food (BLE)","award":["2818SE001"],"award-info":[{"award-number":["2818SE001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Mosquitoes collected from mid-December 2020 to early March 2021 from hibernacula in northeastern Germany, a region of West Nile virus (WNV) activity since 2018, were examined for WNV-RNA. Among the 6101 mosquitoes tested in 722 pools of up to 12 specimens, one pool of 10 Culex pipiens complex mosquitoes collected in early March 2021 in the cellar of a medieval castle in Rosslau, federal state of Saxony-Anhalt, tested positive. Subsequent mosquito DNA analysis produced Culex pipiens biotype pipiens. The pool homogenate remaining after nucleic acid extraction failed to grow the virus on Vero and C6\/36 cells. Sequencing of the viral NS2B-NS3 coding region, however, demonstrated high homology with virus strains previously collected in Germany, e.g., from humans, birds, and mosquitoes, which have been designated the East German WNV clade. The finding confirms the expectation that WNV can overwinter in mosquitoes in Germany, facilitating an early start to the natural transmission season in the subsequent year. On the other hand, the calculated low infection prevalence of 0.016\u20130.20%, depending on whether one or twelve of the mosquitoes in the positive pool was\/were infected, indicates a slow epidemic progress and mirrors the still-hypoendemic situation in Germany. In any case, local overwintering of the virus in mosquitoes suggests its long-term persistence and an enduring public health issue.<\/jats:p>","DOI":"10.3390\/v13122463","type":"journal-article","created":{"date-parts":[[2021,12,10]],"date-time":"2021-12-10T02:07:18Z","timestamp":1639102038000},"page":"2463","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":71,"title":["First Evidence of West Nile Virus Overwintering in Mosquitoes in Germany"],"prefix":"10.3390","volume":"13","author":[{"given":"Helge","family":"Kampen","sequence":"first","affiliation":[{"name":"Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Infectology, 17493 Greifswald-Insel Riems, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8647-0497","authenticated-orcid":false,"given":"Birke Andrea","family":"Tews","sequence":"additional","affiliation":[{"name":"Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Infectology, 17493 Greifswald-Insel Riems, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Doreen","family":"Werner","sequence":"additional","affiliation":[{"name":"Leibniz-Centre for Agricultural Landscape Research, 15374 Muencheberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Byas, A.D., and Ebel, G.D. (2020). Comparative pathology of West Nile virus in humans and non-human animals. Pathogens, 9.","DOI":"10.3390\/pathogens9010048"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1186\/1756-3305-7-323","article-title":"A review of the vector management methods to prevent and control outbreaks of West Nile virus infection and the challenge for Europe","volume":"7","author":"Bellini","year":"2014","journal-title":"Parasit. Vectors"},{"key":"ref_3","first-page":"309","article-title":"The role of birds in the ecology of West Nile virus in Europe and Africa","volume":"267","author":"Malkinson","year":"2002","journal-title":"Curr. Top. Microbiol. Immunol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"635","DOI":"10.1128\/CMR.00045-12","article-title":"West Nile virus: Biology, transmission, and human infection","volume":"25","author":"Colpitts","year":"2012","journal-title":"Clin. Microbiol. Rev."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1097\/QCO.0b013e32816b5cad","article-title":"Experimental infections with West Nile virus","volume":"20","author":"Bowen","year":"2007","journal-title":"Curr. Opin. Infect. Dis."},{"key":"ref_6","unstructured":"ECDC (European Center for Disease Prevention and Control) (2021, October 19). Epidemiological Update: West Nile Virus Transmission Season in Europe, 2018. Available online: https:\/\/www.ecdc.europa.eu\/en\/news-events\/epidemiological-update-west-nile-virus-transmission-season-europe-2018."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1080\/14787210.2020.1713751","article-title":"The knowns and unknowns of West Nile virus in Europe: What did we learn from the 2018 outbreak?","volume":"18","author":"Camp","year":"2020","journal-title":"Expert Rev. Anti. Infect. Ther."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1016\/j.antiviral.2018.12.005","article-title":"West Nile virus epizootic in Germany, 2018","volume":"162","author":"Ziegler","year":"2019","journal-title":"Antivir. Res."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Ziegler, U., Santos, P.D., Groschup, M.H., Hattendorf, C., Eiden, M., H\u00f6per, D., Eisermann, P., Keller, M., Michel, F., and Klopfleisch, R. (2020). West Nile virus epidemic in Germany triggered by epizootic emergence, 2019. Viruses, 12.","DOI":"10.3390\/v12040448"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"2001786","DOI":"10.2807\/1560-7917.ES.2020.25.46.2001786","article-title":"Autochthonous West Nile virus infection outbreak in humans, Leipzig, Germany, August to September 2020","volume":"25","author":"Pietsch","year":"2020","journal-title":"Euro Surveill."},{"key":"ref_11","unstructured":"ECDC (European Center for Disease Prevention and Control) (2021, October 19). Distribution of West Nile Virus Infections among Human and Outbreaks among Equids and\/or Birds in the EU, Transmission Season 2020. Available online: https:\/\/www.ecdc.europa.eu\/sites\/default\/files\/images\/WNF_HumanAndAnimal_Historical2020.png."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Kampen, H., Holicki, C.M., Ziegler, U., Groschup, M.H., Tews, B.A., and Werner, D. (2020). West Nile virus mosquito vectors (Diptera: Culicidae) in Germany. Viruses, 12.","DOI":"10.3390\/v12050493"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"742","DOI":"10.3201\/eid0704.017426","article-title":"West Nile virus in overwintering Culex mosquitoes, New York City, 2000","volume":"7","author":"Nasci","year":"2001","journal-title":"Emerg. Infect. Dis."},{"key":"ref_14","first-page":"326","article-title":"The discovery of West Nile virus in overwintering Culex pipiens (Diptera: Culicidae) mosquitoes in Lehigh County, Pennsylvania","volume":"20","author":"Bugbee","year":"2004","journal-title":"J. Am. Mosq. Control Assoc."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"490","DOI":"10.1093\/jmedent\/42.3.490","article-title":"Detection of West Nile viral RNA from overwintering pool of Culex pipiens pipiens (Diptera: Culicidae) in New Jersey","volume":"42","author":"Farajollahi","year":"2005","journal-title":"J. Med. Entomol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"452","DOI":"10.1186\/s13071-017-2399-7","article-title":"West Nile virus in overwintering mosquitoes, Central Europe","volume":"10","author":"Rudolf","year":"2017","journal-title":"Parasit. Vectors"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"257","DOI":"10.2987\/20-6949.1","article-title":"Overwintering of Culex modestus and other mosquito species in a reedbed ecosystem, including arbovirus findings","volume":"36","author":"Rudolf","year":"2020","journal-title":"J. Am. Mosq. Control Assoc."},{"key":"ref_18","unstructured":"Schaffner, F., Angel, G., Geoffroy, B., Hervy, J.P., Rhaiem, A., and Brunhes, J. (2001). The Mosquitoes of Europe. An Identification and Training Programme, IRD Editions (CD-Rom)."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Becker, N., Petric, D., Zgomba, M., Boase, C., Dahl, C., Madon, M., and Kaiser, A. (2020). Mosquitoes, Springer. [3rd ed.].","DOI":"10.1007\/978-3-030-11623-1"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"80","DOI":"10.1111\/jvec.12286","article-title":"Mosquito species composition and phenology (Diptera, Culicidae) in two German zoological gardens imply different risks of mosquito-borne pathogen transmission","volume":"43","author":"Heym","year":"2018","journal-title":"J. Vector Ecol."},{"key":"ref_21","first-page":"4248756","article-title":"A novel Pan-Flavivirus detection and identification assay based on RT-qPCR and microarray","volume":"2017","author":"Sachse","year":"2017","journal-title":"Biomed. Res. Int."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"286","DOI":"10.1016\/j.virol.2007.06.016","article-title":"Direct broad-range detection of alphaviruses in mosquito extracts","volume":"368","author":"Eshoo","year":"2007","journal-title":"Virology"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"748","DOI":"10.1177\/104063871002200515","article-title":"Two new real-time quantitative reverse transcription polymerase chain reaction assays with unique target sites for the specific and sensitive detection of lineages 1 and 2 West Nile virus strains","volume":"22","author":"Eiden","year":"2010","journal-title":"J. Vet. Diagn. Investig."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"436","DOI":"10.3201\/eid1403.070463","article-title":"Genetic variability of West Nile virus in US blood donors, 2002\u20132005","volume":"14","author":"Grinev","year":"2008","journal-title":"Emerg. Infect. Dis."},{"key":"ref_25","unstructured":"CDC (Centers for Disease Control and Prevention) (2021, November 01). West Nile Virus\u2014Resources, Available online: https:\/\/www.cdc.gov\/westnile\/resourcepages\/mosqSurvSoft.html."},{"key":"ref_26","first-page":"407","article-title":"Die Culicidenvorkommen in den Rheinauen des Oberrheingebiets mit besonderer Ber\u00fccksichtigung von Uranotaenia (Culicidae, Diptera)\u2014einer neuen Stechm\u00fcckengattung f\u00fcr Deutschland","volume":"10","author":"Becker","year":"1995","journal-title":"Mitt. Dtsch. Ges. Allg. Angew. Entomol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"3437","DOI":"10.1007\/s00436-017-5652-2","article-title":"The thermophilic mosquito species Uranotaenia unguiculata Edwards, 1913 (Diptera: Culicidae) moves north in Germany","volume":"116","author":"Tippelt","year":"2017","journal-title":"Parasitol. Res."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Jansen, S., Heitmann, A., L\u00fchken, R., Leggewie, M., Helms, M., Badusche, M., Rossini, G., Schmidt-Chanasit, J., and Tannich, E. (2019). Culex torrentium: A potent vector for the transmission of West Nile virus in central Europe. Viruses, 11.","DOI":"10.3390\/v11060492"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Holicki, C.M., Ziegler, U., R\u0103ileanu, C., Kampen, H., Werner, D., Schulz, J., Silaghi, C., Groschup, M.H., and Vasi\u0107, A. (2020). West Nile virus lineage 2 vector competence of indigenous Culex and Aedes mosquitoes from Germany at temperate climate conditions. Viruses, 12.","DOI":"10.3390\/v12050561"},{"key":"ref_30","first-page":"361","article-title":"Isolation in Portugal of West Nile virus from Anopheles maculipennis mosquitoes","volume":"16","author":"Filipe","year":"1972","journal-title":"Acta Virol."},{"key":"ref_31","first-page":"85","article-title":"West Nile virus and other zoonotic viruses in Russia: Examples of emerging-reemerging situations","volume":"18","author":"Lvov","year":"2004","journal-title":"Arch. Virol."},{"key":"ref_32","unstructured":"CDC (Centers for Disease Control and Prevention) (2021, October 19). Mosquito Species in which West Nile Virus Has Been Detected, United States, 1999\u20132016, Available online: https:\/\/www.cdc.gov\/westnile\/resources\/pdfs\/MosquitoSpecies1999-2016.pdf."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"500","DOI":"10.1007\/s13337-014-0234-8","article-title":"Putative novel lineage of West Nile virus in Uranotaenia unguiculata mosquito, Hungary","volume":"25","author":"Kemenesi","year":"2014","journal-title":"Virus Dis."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1007\/978-3-319-94075-5_5","article-title":"Vector potential of mosquito species (Diptera: Culicidae) occurring in Central Europe","volume":"10","author":"Kampen","year":"2018","journal-title":"Parasitol. Res. Monogr."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"589","DOI":"10.1089\/vbz.2007.0266","article-title":"Vector competence of some French Culex and Aedes mosquitoes for West Nile virus","volume":"8","author":"Balenghien","year":"2008","journal-title":"Vector-Borne Zoon. Dis."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"462","DOI":"10.1603\/0022-2585-38.3.462","article-title":"Effect of incubation at overwintering temperatures on the replication of West Nile virus in New York Culex pipiens (Diptera: Culicidae)","volume":"38","author":"Dohm","year":"2001","journal-title":"J. Med. Entomol."},{"key":"ref_37","first-page":"e2000063","article-title":"Mosquito surveillance of West Nile and Usutu viruses in four territorial units of Slovakia and description of a confirmed autochthonous human case of West Nile fever, 2018 to 2019","volume":"26","author":"Bradbury","year":"2021","journal-title":"Euro Surveill."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"243","DOI":"10.3389\/fvets.2020.00243","article-title":"Enhanced West Nile virus circulation in the Emilia-Romagna and Lombardy regions (northern Italy) in 2018 detected by entomological surveillance","volume":"7","author":"Calzolari","year":"2020","journal-title":"Front. Vet. Sci."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Klobucar, A., Savic, V., Curman Posavec, M., Petrinic, S., Kuhar, U., Toplak, I., Madic, J., and Vilibic-Cavlek, T. (2021). Screening of mosquitoes for West Nile virus and Usutu virus in Croatia, 2015\u20132020. Trop. Med. Infect. Dis., 6.","DOI":"10.3390\/tropicalmed6020045"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1186\/s13071-021-04736-z","article-title":"West Nile and Usutu viruses co-circulation in Central Italy: Outcomes of the 2018 integrated surveillance","volume":"14","author":"Scaramozzino","year":"2021","journal-title":"Parasit. Vectors"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"679","DOI":"10.3201\/eid0704.017415","article-title":"West Nile virus infection in birds and mosquitoes, New York State, 2000","volume":"7","author":"Bernard","year":"2001","journal-title":"Emerg. Infect. Dis."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"e105514","DOI":"10.1016\/j.actatropica.2020.105514","article-title":"West Nile virus lineage 2 in Culex mosquitoes in Thessaly, Greece, 2019","volume":"208","author":"Papa","year":"2020","journal-title":"Acta Trop."},{"key":"ref_43","unstructured":"FLI (Friedrich-Loeffler-Institut) (2021, October 19). West Nile Virus. Available online: https:\/\/www.fli.de\/en\/news\/animal-disease-situation\/west-nile-virus."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1038\/sj.hdy.6884120","article-title":"Culex pipiens in London Underground tunnels: Differentiation between surface and subterranean populations","volume":"82","author":"Byrne","year":"1999","journal-title":"Heredity"},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Brugman, V.A., Hern\u00e1ndez-Triana, L.M., Medlock, J.M., Fooks, A.R., Carpenter, S., and Johnson, N. (2018). The role of Culex pipiens L. (Diptera: Culicidae) in virus transmission in Europe. Int. J. Environ. Res. Public Health, 15.","DOI":"10.3390\/ijerph15020389"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"6088","DOI":"10.1038\/s41598-018-24133-4","article-title":"Overwintering of West Nile virus in a bird community with a communal crow roost","volume":"8","author":"Barker","year":"2018","journal-title":"Sci. Rep."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"1498","DOI":"10.1093\/jme\/tjz070","article-title":"Overwintering of West Nile virus in the United States","volume":"56","author":"Reisen","year":"2019","journal-title":"J. Med. Entomol."}],"container-title":["Viruses"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1999-4915\/13\/12\/2463\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T07:43:56Z","timestamp":1760168636000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1999-4915\/13\/12\/2463"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,12,9]]},"references-count":47,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2021,12]]}},"alternative-id":["v13122463"],"URL":"https:\/\/doi.org\/10.3390\/v13122463","relation":{},"ISSN":["1999-4915"],"issn-type":[{"value":"1999-4915","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,12,9]]}}}