{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,30]],"date-time":"2026-10-30T03:54:10Z","timestamp":1793332450275,"version":"4.5.0"},"reference-count":16,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2022,2,14]],"date-time":"2022-02-14T00:00:00Z","timestamp":1644796800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2022,2,14]],"date-time":"2022-02-14T00:00:00Z","timestamp":1644796800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["R01AI137395"],"award-info":[{"award-number":["R01AI137395"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Parasites Vectors"],"published-print":{"date-parts":[[2022,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Background<\/jats:title>\n                <jats:p><jats:italic>Plasmodium ovale<\/jats:italic> is a neglected malarial parasite that can form latent hypnozoites in the human liver. Over the last decade, molecular surveillance studies of non-falciparum malaria in Africa have highlighted that <jats:italic>P. ovale<\/jats:italic> is circulating below the radar, including areas where <jats:italic>Plasmodium falciparum<\/jats:italic> is in decline. To eliminate malaria where <jats:italic>P. ovale<\/jats:italic> is endemic, a better understanding of its epidemiology, asymptomatic carriage, and transmission biology is needed.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>We performed a pilot study on <jats:italic>P. ovale<\/jats:italic> transmission as part of an ongoing study of human-to-mosquito transmission of <jats:italic>P. falciparum<\/jats:italic> from asymptomatic carriers. To characterize the malaria asymptomatic reservoir, cross-sectional qPCR surveys were conducted in Bagamoyo, Tanzania, over three transmission seasons. Positive individuals were enrolled in transmission studies of <jats:italic>P. falciparum<\/jats:italic> using direct skin feeding assays (DFAs) with <jats:italic>Anopheles gambiae<\/jats:italic> s.s. (IFAKARA strain) mosquitoes. For a subset of participants who screened positive for <jats:italic>P. ovale<\/jats:italic> on the day of DFA, we incubated blood-fed mosquitoes for 14\u00a0days to assess sporozoite development.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>Molecular surveillance of asymptomatic individuals revealed a <jats:italic>P. ovale<\/jats:italic> prevalence of 11% (300\/2718), compared to 29% (780\/2718) for <jats:italic>P. falciparum<\/jats:italic>. Prevalence for <jats:italic>P. ovale<\/jats:italic> was highest at the beginning of the long rainy season (15.5%, 128\/826) in contrast to <jats:italic>P. falciparum<\/jats:italic>, which peaked later in both the long and short rainy seasons. Considering that these early-season <jats:italic>P. ovale<\/jats:italic> infections were low-density mono-infections (127\/128), we speculate many were due to hypnozoite-induced relapse. Six of eight <jats:italic>P. ovale<\/jats:italic>-infected asymptomatic individuals who underwent DFAs successfully transmitted <jats:italic>P. ovale<\/jats:italic> parasites to <jats:italic>A. gambiae<\/jats:italic>.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p><jats:italic>Plasmodium ovale<\/jats:italic> is circulating at 4\u201315% prevalence among asymptomatic individuals in coastal Tanzania, largely invisible to field diagnostics. A different seasonal peak from co-endemic <jats:italic>P. falciparum<\/jats:italic>, the capacity to relapse, and efficient transmission to <jats:italic>Anopheles<\/jats:italic> vectors likely contribute to its persistence amid control efforts focused on <jats:italic>P. falciparum<\/jats:italic>.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Graphical Abstract<\/jats:title>\n                \n              <\/jats:sec>","DOI":"10.1186\/s13071-022-05181-2","type":"journal-article","created":{"date-parts":[[2022,2,14]],"date-time":"2022-02-14T12:03:03Z","timestamp":1644840183000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Seasonality and transmissibility of Plasmodium ovale in Bagamoyo District, Tanzania"],"prefix":"10.1186","volume":"15","author":[{"given":"Brian B.","family":"Tarimo","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vincent O.","family":"Nyasembe","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Billy","family":"Ngasala","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher","family":"Basham","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Isaack J.","family":"Rutagi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meredith","family":"Muller","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Srijana B.","family":"Chhetri","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rebecca","family":"Rubinstein","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan J.","family":"Juliano","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mwajabu","family":"Loya","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rhoel R.","family":"Dinglasan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jessica T.","family":"Lin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8743-7285","authenticated-orcid":false,"given":"Derrick K.","family":"Mathias","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2022,2,14]]},"reference":[{"key":"5181_CR1","doi-asserted-by":"publisher","first-page":"808","DOI":"10.1016\/j.pt.2016.07.001","volume":"32","author":"CJ Sutherland","year":"2016","unstructured":"Sutherland CJ. Persistent parasitism: the adaptive biology of malariae and ovale malaria. Trends Parasitol. 2016;32:808\u201319.","journal-title":"Trends Parasitol"},{"key":"5181_CR2","doi-asserted-by":"publisher","first-page":"1005","DOI":"10.1093\/infdis\/jiaa478","volume":"223","author":"CL Mitchell","year":"2021","unstructured":"Mitchell CL, Brazeau NF, Keeler C, Mwandagalirwa MK, Tshefu AK, Juliano JJ, et al. Under the radar: epidemiology of Plasmodium ovale in the Democratic Republic of the Congo. J Infect Dis. 2021;223:1005\u201314.","journal-title":"J Infect Dis"},{"key":"5181_CR3","doi-asserted-by":"publisher","first-page":"1544","DOI":"10.1086\/652240","volume":"201","author":"CJ Sutherland","year":"2010","unstructured":"Sutherland CJ, Tanomsing N, Nolder D, Oguike M, Jennison C, Pukrittayakamee S, et al. Two nonrecombining sympatric forms of the human malaria parasite Plasmodium ovale occur globally. 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Clin Infect Dis. 2019;69:2119\u201326.","journal-title":"Clin Infect Dis"},{"key":"5181_CR16","doi-asserted-by":"publisher","first-page":"2191","DOI":"10.1038\/s41598-019-38629-0","volume":"9","author":"R Zhou","year":"2019","unstructured":"Zhou R, Li S, Zhao Y, Yang C, Liu Y, Qian D, et al. Characterization of Plasmodium ovale spp. imported from Africa to Henan Province, China. 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Informed consent in Kiswahili was obtained prior to screening for malaria and for enrollment into the mosquito feeding portion of the study.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare that they have no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"56"}}