{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T13:26:40Z","timestamp":1779197200776,"version":"3.51.4"},"reference-count":32,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2021,10,29]],"date-time":"2021-10-29T00:00:00Z","timestamp":1635465600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2021,10,29]],"date-time":"2021-10-29T00:00:00Z","timestamp":1635465600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100001713","name":"European and Developing Countries Clinical Trials Partnership","doi-asserted-by":"publisher","award":["TMA 2015 SF-998"],"award-info":[{"award-number":["TMA 2015 SF-998"]}],"id":[{"id":"10.13039\/501100001713","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Malar J"],"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Background<\/jats:title>\n                <jats:p>Asymptomatic malaria infections largely remain undetected and act as a reservoir for continuous transmission. The study assessed the prevalence of submicroscopic asymptomatic malaria infections and anaemia in two rural low (300\u00a0m above sea level) and highland (700\u00a0m asl) settings of Korogwe District north-eastern Tanzania.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>A cross-sectional malariometric survey involving individuals aged 0\u201319 years was conducted in June 2018 in the two rural villages. Venous blood was collected from eligible study participants for estimation of haemoglobin level, detection of malaria by rapid diagnostic test (RDT), quantification of malaria parasitaemia by microscopy, as well as dried blood spot (DBS) for determining submicroscopic infections by PCR targeting the small subunit of the ribosomal ribonucleic acid (ssrRNA) of human <jats:italic>Plasmodium.<\/jats:italic><\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>Out of 565 individuals tested, 211 (37.3%) were malaria positive based on RDT, whereas only 81 (14.3%) were positive by microscopy. There was no significant difference in the prevalence between the highland and the lowland village, p\u2009=\u20090.19 and p\u2009=\u20090.78 microscopy and RDT, respectively. Three out of 206 (1.5%) RDT\/microscopy negative samples were <jats:italic>P. falciparum<\/jats:italic> positive by PCR. Of the 211 RDT and 81 microscopy positive, 130 (61.6%) and 33 (40.7%), respectively, were defined as being asymptomatic. Of the 565 individuals, 135 (23.9%) were anaemic (haemoglobin\u2009&lt;\u200911\u00a0g\/dL) out of which 5.2% were severely anaemic. The risk of being anaemic was significantly higher among individuals with asymptomatic malaria as compared to those without malaria as confirmed by RDT (AOR\u2009=\u20092.06 (95% CI 1.32\u20133.20) while based on microscopic results there was no significant differences observed (AOR\u2009=\u20092.09, 95% CI 0.98\u20134.47). Age and altitude had no effect on the risk of anaemia even after adjusting for asymptomatic malaria.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>Asymptomatic malaria is associated with an increased risk of having anaemia in the study communities. The findings highlight the need for targeted interventions focusing on asymptomatic infections which is an important risks factor for anaemia in the community and act as a source of continued transmission of malaria in the study area.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s12936-021-03952-3","type":"journal-article","created":{"date-parts":[[2021,10,29]],"date-time":"2021-10-29T10:04:04Z","timestamp":1635501844000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":36,"title":["Prevalence of asymptomatic malaria, submicroscopic parasitaemia and anaemia in Korogwe District, north-eastern Tanzania"],"prefix":"10.1186","volume":"20","author":[{"given":"Paul M.","family":"Hayuma","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christian W.","family":"Wang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Edwin","family":"Liheluka","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vito","family":"Baraka","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rashid A.","family":"Madebe","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniel T. 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The study was also approved by Institutional Review Board (IRB) of Sokoine University of Agriculture (SUA) with reference number SUA\/ADM\/R.1\/8\/232. Prior to data collection, sensitization meetings were held with potential study participants in the respective study communities. The study objectives were explained to participants in Kiswahili, a language understood by the parents and guardians with emphasis laid upon voluntary participation. Written informed consent to participate was obtained from each study participant or their parents\/guardians.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval\u00a0and consent to participate"}},{"value":"This manuscript is published with permission from the Director General of the National Institute for Medical Research, Tanzania.","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":"424"}}