{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T23:52:08Z","timestamp":1791935528583,"version":"4.3.4"},"reference-count":61,"publisher":"Cambridge University Press (CUP)","issue":"4","license":[{"start":{"date-parts":[[2003,10,17]],"date-time":"2003-10-17T00:00:00Z","timestamp":1066348800000},"content-version":"unspecified","delay-in-days":16,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Parasitology"],"published-print":{"date-parts":[[2003,10]]},"abstract":"<jats:p><jats:italic>Babesia microti<\/jats:italic>(Apicomplexa: Piroplasmida) has historically been considered a common parasite of Holarctic rodents. However, human babesiosis due to this species has generally been limited to the northeastern seaboard of the United States and Minnesota and Wisconsin. The absence of reports of<jats:italic>B. microti<\/jats:italic>babesiosis from sites where the agent is enzootic, such as in western Europe, remains unexplained. Previous work focusing on the 18S rDNA demonstrates little sequence diversity among samples from allopatric host populations across a wide geographical area. It may be that genetic diversity is underestimated due to sample size or the gene analysed. Accordingly, we collected blood or spleen samples from American or Eurasian animals with parasites that were morphologically consistent with<jats:italic>B. microti<\/jats:italic>, amplified the 18S rDNA and<jats:italic>beta<\/jats:italic>-tubulin gene, and conducted phylogenetic analysis. Surprisingly, what was considered to be \u2018<jats:italic>B. microti<\/jats:italic>\u2019 by microscopy appears to be a diverse species complex. We identify 3 distinct clades within this complex, including parasites from non-rodent hosts. Rodent parasites comprise 2 clades, one representing zoonotic isolates, and the other apparently maintained in microtine rodents, and therefore their morphological detection within animals from a site does not necessarily imply a risk to public health.<\/jats:p>","DOI":"10.1017\/s0031182003003822","type":"journal-article","created":{"date-parts":[[2003,10,17]],"date-time":"2003-10-17T13:42:34Z","timestamp":1066398154000},"page":"301-309","source":"Crossref","is-referenced-by-count":118,"title":["What is<i>Babesia microti<\/i>?"],"prefix":"10.1017","volume":"127","author":[{"given":"H. K.","family":"GOETHERT","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S. R.","family":"TELFORD","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"56","published-online":{"date-parts":[[2003,10,17]]},"reference":[{"key":"S0031182003003822_ref035","doi-asserted-by":"publisher","DOI":"10.2307\/3224894"},{"key":"S0031182003003822_ref049","doi-asserted-by":"crossref","unstructured":"TELFORD, S. R., 3rd , GORENFLOT, A. , BRASSEUR, P. & SPIELMAN, A. (1993).Babesial infections in humans and wildlife. In Parasitic Protozoa , vol. 5 (ed. Kreier, J. P. ), pp. 1\u201347.Academic Press,San Diego, CA, USA.","DOI":"10.1016\/B978-0-12-426015-3.50006-6"},{"key":"S0031182003003822_ref060","doi-asserted-by":"crossref","unstructured":"ZAHLER, M. , RINDER, H. & GOTHE, R. 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(2000). DNA Sequence Polymorphism . Universitat de Barcelona, Barcelona."},{"key":"S0031182003003822_ref057","doi-asserted-by":"publisher","DOI":"10.1016\/0378-1119(89)90116-9"},{"key":"S0031182003003822_ref009","doi-asserted-by":"publisher","DOI":"10.1136\/vr.149.18.552"},{"key":"S0031182003003822_ref031","unstructured":"KILLICK-KENDRICK, R. (1974).Parasitic protozoa of the blood of rodents II. Hemogregarines, malaria parasites and piroplasms of rodents: an annotated check list and host index.Acta Tropica 31, 29\u201369."},{"key":"S0031182003003822_ref030","unstructured":"KARBOWIAK, G. , STANKO, M. , RYCHLIK, L. , NOWAKOWSKI, W. & SIUDA, K. 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