{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T05:03:53Z","timestamp":1789967033054,"version":"4.0.1"},"reference-count":45,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T00:00:00Z","timestamp":1789948800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>China was certified malaria-free by the World Health Organization in 2021; however, imported malaria remains a significant challenge to maintaining malaria elimination due to increasing international travel and overseas population mobility. Imported malaria cases have been continuously reported in Shandong Province, but detailed clinical characteristics, parasite species distribution, travel history, and treatment patterns among hospitalised malaria patients following elimination remain insufficiently characterised.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      We conducted a retrospective hospital-based observational study of malaria patients admitted to our hospital in Shandong Province, China, from January 2021 to June 2026. Demographic information, travel history, clinical manifestations, laboratory findings,\n                      <jats:italic>Plasmodium<\/jats:italic>\n                      species identification, and antimalarial treatments were analysed. The associations between travel regions and\n                      <jats:italic>Plasmodium<\/jats:italic>\n                      species distribution were evaluated using chi-square tests.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      A total of 120 hospitalised malaria patients were included in the analysis. The number of malaria admissions increased from two cases in 2021 to 45 cases in 2025, with seasonal clustering during the second and third quarters of the year. All patients were male, and 98.3% were aged 30\u201359 years. Most patients had a travel history to Africa (95.8%), particularly West Africa (54.2%) and Central Africa (28.3%). Among the 120 patients with confirmed parasite identification,\n                      <jats:italic>Plasmodium falciparum<\/jats:italic>\n                      (\n                      <jats:italic>P. falciparum<\/jats:italic>\n                      ) was the predominant species (67.5%), followed by\n                      <jats:italic>Plasmodium ovale<\/jats:italic>\n                      (\n                      <jats:italic>P. ovale<\/jats:italic>\n                      ) (20.0%),\n                      <jats:italic>Plasmodium vivax<\/jats:italic>\n                      (\n                      <jats:italic>P. vivax<\/jats:italic>\n                      ) (7.5%), and\n                      <jats:italic>Plasmodium malariae<\/jats:italic>\n                      (\n                      <jats:italic>P. malariae<\/jats:italic>\n                      ) (5.0%). Fever was observed in all patients. The distribution of\n                      <jats:italic>Plasmodium<\/jats:italic>\n                      species differed significantly according to travel regions (Monte Carlo simulated\n                      <jats:italic>P<\/jats:italic>\n                      \u00a0&amp;lt;\u00a00.001). Further analysis within Africa revealed a significant difference among West, Central, and East Africa (Monte Carlo simulated\n                      <jats:italic>P<\/jats:italic>\n                      \u00a0=\u00a00.016). All patients received antimalarial treatment. Artemisinin-based therapies were the main treatment strategies, with dihydroartemisinin\u2013piperaquine used in 90.0% of patients and intravenous artesunate administered in 41.7% of cases.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Imported malaria remains a significant clinical and public health challenge following malaria elimination in Shandong Province. Cases are predominantly identified among working-age males returning from sub-Saharan Africa, with P. falciparum as the dominant parasite species. Therefore, strengthening surveillance of overseas travellers, improving early diagnosis, and maintaining standardised treatment protocols are essential to prevent the re-establishment of malaria.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fcimb.2026.1952587","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T04:28:55Z","timestamp":1789964935000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Epidemiological and clinical characteristics of imported malaria patients admitted to a specialized hospital: a retrospective study (2021\u2013 June 2026)"],"prefix":"10.3389","volume":"16","author":[{"given":"Kun","family":"Peng","sequence":"first","affiliation":[{"name":"Digestive Disease Hospital of Shandong First Medical University, Shandong First Medical University & Shandong Academy of Medical Sciences","place":["Jining, Shandong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenjing","family":"Gong","sequence":"additional","affiliation":[{"name":"Digestive Disease Hospital of Shandong First Medical University, Shandong First Medical University & Shandong Academy of Medical Sciences","place":["Jining, Shandong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuan","family":"Dong","sequence":"additional","affiliation":[{"name":"Digestive Disease Hospital of Shandong First Medical University, Shandong First Medical University & Shandong Academy of Medical Sciences","place":["Jining, Shandong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yunjing","family":"Zhao","sequence":"additional","affiliation":[{"name":"Digestive Disease Hospital of Shandong First Medical University, Shandong First Medical University & Shandong Academy of Medical Sciences","place":["Jining, Shandong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Li","family":"Zhang","sequence":"additional","affiliation":[{"name":"Digestive Disease Hospital of Shandong First Medical University, Shandong First Medical University & Shandong Academy of Medical Sciences","place":["Jining, Shandong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chuanbing","family":"Zhu","sequence":"additional","affiliation":[{"name":"Digestive Disease Hospital of Shandong First Medical University, Shandong First Medical University & Shandong Academy of Medical Sciences","place":["Jining, Shandong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nuo","family":"Xu","sequence":"additional","affiliation":[{"name":"Digestive Disease Hospital of Shandong First Medical University, Shandong First Medical University & Shandong Academy of Medical Sciences","place":["Jining, Shandong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiang","family":"Li","sequence":"additional","affiliation":[{"name":"Digestive Disease Hospital of Shandong First Medical University, Shandong First Medical University & Shandong Academy of Medical Sciences","place":["Jining, Shandong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yihan","family":"Guo","sequence":"additional","affiliation":[{"name":"Digestive Disease Hospital of Shandong First Medical University, Shandong First Medical University & Shandong Academy of Medical Sciences","place":["Jining, Shandong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanmei","family":"Shen","sequence":"additional","affiliation":[{"name":"Digestive Disease Hospital of Shandong First Medical University, Shandong First Medical University & Shandong Academy of Medical Sciences","place":["Jining, Shandong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongli","family":"Zhao","sequence":"additional","affiliation":[{"name":"Digestive Disease Hospital of Shandong First Medical University, Shandong First Medical University & Shandong Academy of Medical Sciences","place":["Jining, Shandong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,21]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1186\/s12916-018-1207-3","article-title":"Association of mutations in the Plasmodium falciparum Kelch13 gene (Pf3D7_1343700) with parasite clearance rates after artemisinin-based treatments\u2014a WWARN individual patient data meta-analysis","volume":"17","author":"Amaratunga","year":"2019","journal-title":"BMC Med."},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pntd.0011884","article-title":"Seasonal prediction of the distribution of three major malaria vectors in China: Based on an ecological niche model","volume":"18","author":"An","year":"2024","journal-title":"PloS Negl.Trop. 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