{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T14:00:15Z","timestamp":1790690415030,"version":"4.1.0"},"reference-count":37,"publisher":"Oxford University Press (OUP)","issue":"7","license":[{"start":{"date-parts":[[2021,7,3]],"date-time":"2021-07-03T00:00:00Z","timestamp":1625270400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004359","name":"Swedish Research Council","doi-asserted-by":"publisher","award":["2018-04468"],"award-info":[{"award-number":["2018-04468"]}],"id":[{"id":"10.13039\/501100004359","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004348","name":"Stockholm County Council","doi-asserted-by":"publisher","award":["SLL20150135"],"award-info":[{"award-number":["SLL20150135"]}],"id":[{"id":"10.13039\/501100004348","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004348","name":"Stockholm County Council","doi-asserted-by":"publisher","award":["FoUI-953118"],"award-info":[{"award-number":["FoUI-953118"]}],"id":[{"id":"10.13039\/501100004348","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,4,9]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>The effect of primaquine in preventing Plasmodium vivax relapses from dormant stages is well established. For Plasmodium ovale, the relapse characteristics and the use of primaquine is not as well studied. We set to evaluate the relapsing properties of these 2 species, in relation to primaquine use among imported malaria cases in a nonendemic setting.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>We performed a nationwide retrospective study of malaria diagnosed in Sweden 1995\u20132019, by reviewing medical records of 3254 cases. All episodes of P. vivax (n\u2005=\u2005972) and P. ovale (n\u2005=\u2005251) were selected for analysis.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>First time relapses were reported in 80\/857 (9.3%) P. vivax and 9\/220 (4.1%) P. ovale episodes, respectively (P\u2005&amp;lt;\u2005.01). Without primaquine, the risk for relapse was higher in P. vivax, 20\/60 (33.3%), compared to 3\/30 (10.0%) in P. ovale (hazard ratio [HR] 3.5, 95% confidence interval [CI] 1.0\u201312.0). In P. vivax, patients prescribed primaquine had a reduced risk of relapse compared to episodes without relapse preventing treatment, 7.1% vs 33.3% (HR 0.2, 95% CI .1\u2013.3). In P. ovale, the effect of primaquine on the risk of relapse did not reach statistical significance, with relapses seen in 2.8% of the episodes compared to 10.0% in patients not receiving relapse preventing treatment (HR 0.3, 95% CI .1\u20131.1).<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>The risk of relapse was considerably lower in P. ovale than in P. vivax infections indicating different relapsing features between the two species. Primaquine was effective in preventing P. vivax relapse. In P. ovale, relapse episodes were few, and the supportive evidence for primaquine remains limited.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/cid\/ciab610","type":"journal-article","created":{"date-parts":[[2021,7,1]],"date-time":"2021-07-01T19:46:18Z","timestamp":1625168778000},"page":"1199-1207","source":"Crossref","is-referenced-by-count":25,"title":["Relapse of <i>Plasmodium vivax<\/i> and <i>Plasmodium ovale<\/i> Malaria With and Without Primaquine Treatment in a Nonendemic Area"],"prefix":"10.1093","volume":"74","author":[{"given":"Andreas","family":"W\u00e5ngdahl","sequence":"first","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden"},{"name":"Department of Infectious Diseases, V\u00e4ster\u00e5s Hospital, V\u00e4ster\u00e5s, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Klara","family":"Sond\u00e9n","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden"},{"name":"Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katja","family":"Wyss","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden"},{"name":"Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christine","family":"Stenstr\u00f6m","sequence":"additional","affiliation":[{"name":"Department of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David","family":"Bj\u00f6rklund","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jessica","family":"Zhang","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helena","family":"Hervius Askling","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden"},{"name":"Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christina","family":"Carlander","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, V\u00e4ster\u00e5s Hospital, V\u00e4ster\u00e5s, Sweden"},{"name":"Division of Infectious Diseases, Department of Medicine Huddinge, Karolinska Institutet, Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Urban","family":"Hellgren","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden"},{"name":"Division of Infectious Diseases, Department of Medicine Huddinge, Karolinska Institutet, Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"F\u00e4rnert","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine Solna, Karolinska Institutet, Stockholm, Sweden"},{"name":"Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2021,7,3]]},"reference":[{"key":"2022040917420268700_CIT0001","volume-title":"World malaria report 2020","author":"WHO.","year":"2020"},{"key":"2022040917420268700_CIT0002","doi-asserted-by":"crossref","first-page":"e0007414","DOI":"10.1371\/journal.pntd.0007414","article-title":"Persistent transmission of Plasmodium malariae and Plasmodium ovale species in an area of declining Plasmodium falciparum transmission in eastern Tanzania","volume":"13","author":"Yman","year":"2019","journal-title":"PLoS Negl Trop Dis"},{"key":"2022040917420268700_CIT0003","doi-asserted-by":"crossref","first-page":"332","DOI":"10.1016\/S0140-6736(19)31096-7","article-title":"Mapping the global endemicity and clinical burden of Plasmodium vivax, 2000\u201317: a spatial and temporal modelling study","volume":"394","author":"Battle","year":"2019","journal-title":"Lancet"},{"key":"2022040917420268700_CIT0004","doi-asserted-by":"crossref","first-page":"15","DOI":"10.4269\/ajtmh.16-0141","article-title":"Global epidemiology of Plasmodium vivax","volume":"95","author":"Howes","year":"2016","journal-title":"Am J Trop Med Hyg"},{"key":"2022040917420268700_CIT0005","doi-asserted-by":"crossref","first-page":"112","DOI":"10.1186\/s12936-017-1759-2","article-title":"A systematic review of the clinical presentation, treatment and relapse characteristics of human Plasmodium ovale malaria","volume":"16","author":"Groger","year":"2017","journal-title":"Malar J"},{"key":"2022040917420268700_CIT0006","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1186\/1475-2875-10-297","article-title":"Determinants of relapse periodicity in Plasmodium vivax malaria","volume":"10","author":"White","year":"2011","journal-title":"Malar J"},{"key":"2022040917420268700_CIT0007","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1016\/B978-0-12-397900-1.00002-5","article-title":"Relapse","volume":"80","author":"White","year":"2012","journal-title":"Adv Parasitol"},{"key":"2022040917420268700_CIT0008","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1128\/mBio.00625-18","article-title":"Bone marrow is a major parasite reservoir in Plasmodium vivax infection","volume":"9","author":"Obaldia","year":"2018","journal-title":"mBio"},{"key":"2022040917420268700_CIT0009","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1186\/1475-2875-13-144","article-title":"Geographical variation in Plasmodium vivax relapse","volume":"13","author":"Battle","year":"2014","journal-title":"Malar J"},{"key":"2022040917420268700_CIT0010","doi-asserted-by":"crossref","first-page":"885","DOI":"10.1080\/14787210.2016.1220304","article-title":"Management of relapsing Plasmodium vivax malaria","volume":"14","author":"Chu","year":"2016","journal-title":"Expert Rev Anti Infect Ther"},{"key":"2022040917420268700_CIT0011","doi-asserted-by":"crossref","first-page":"e1003561","DOI":"10.1371\/journal.pmed.1003561","article-title":"The prevention and treatment of Plasmodium vivax malaria","volume":"18","author":"Chu","year":"2021","journal-title":"PLoS Med"},{"key":"2022040917420268700_CIT0012","doi-asserted-by":"crossref","first-page":"1285","DOI":"10.1007\/s00436-010-2071-z","article-title":"What is the evidence for the existence of Plasmodium ovale hypnozoites?","volume":"107","author":"Richter","year":"2010","journal-title":"Parasitol Res"},{"key":"2022040917420268700_CIT0013","volume-title":"Guidelines for the treatment of malaria","year":"2015","edition":"3"},{"key":"2022040917420268700_CIT0014","doi-asserted-by":"crossref","first-page":"215","DOI":"10.1056\/NEJMoa1710775","article-title":"Single-dose tafenoquine to prevent relapse of Plasmodium vivax malaria","volume":"380","author":"Lacerda","year":"2019","journal-title":"N Engl J Med"},{"key":"2022040917420268700_CIT0015","doi-asserted-by":"crossref","first-page":"229","DOI":"10.1056\/NEJMoa1802537","article-title":"Tafenoquine versus primaquine to prevent relapse of Plasmodium vivax malaria","volume":"380","author":"Llanos-Cuentas","year":"2019","journal-title":"N Engl J Med"},{"key":"2022040917420268700_CIT0016","doi-asserted-by":"crossref","first-page":"1336","DOI":"10.1086\/424663","article-title":"Primaquine therapy for malaria","volume":"39","author":"Baird","year":"2004","journal-title":"Clin Infect Dis"},{"key":"2022040917420268700_CIT0017","volume-title":"WHO guidelines for malaria. Geneva: World Health Organization,","author":"WHO.","year":"2021"},{"key":"2022040917420268700_CIT0018"},{"key":"2022040917420268700_CIT0019","doi-asserted-by":"crossref","first-page":"949","DOI":"10.1093\/cid\/cix437","article-title":"Obesity and diabetes as risk factors for severe Plasmodium falciparum malaria: results from a Swedish nationwide study","volume":"65","author":"Wyss","year":"2017","journal-title":"Clin Infect Dis"},{"key":"2022040917420268700_CIT0020","doi-asserted-by":"crossref","first-page":"1335","DOI":"10.1093\/infdis\/jiz292","article-title":"Severity of Plasmodium falciparum and non-falciparum malaria in travelers and migrants: a nationwide observational study over 2 decades in Sweden","volume":"220","author":"W\u00e5ngdahl","year":"2019","journal-title":"J Infect Dis"},{"key":"2022040917420268700_CIT0021","doi-asserted-by":"crossref","first-page":"1025","DOI":"10.1016\/S1473-3099(18)30348-7","article-title":"The effect of chloroquine dose and primaquine on Plasmodium vivax recurrence: a WorldWide Antimalarial Resistance Network systematic review and individual patient pooled meta-analysis","volume":"18","author":"Commons","year":"2018","journal-title":"Lancet Infect Dis"},{"key":"2022040917420268700_CIT0022","author":"UN."},{"key":"2022040917420268700_CIT0023","volume-title":"World malaria report. Geneva: World Health Organization,","author":"WHO.","year":"2019"},{"key":"2022040917420268700_CIT0024","doi-asserted-by":"crossref","first-page":"975","DOI":"10.1128\/JCM.01858-08","article-title":"Multiplexed real-time PCR assay for discrimination of Plasmodium species with improved sensitivity for mixed infections","volume":"47","author":"Shokoples","year":"2009","journal-title":"J Clin Microbiol"},{"key":"2022040917420268700_CIT0025","doi-asserted-by":"crossref","first-page":"1","DOI":"10.2807\/1560-7917.ES.2019.24.5.1800139","article-title":"Malaria in Eritrean migrants newly arrived in seven European countries, 2011 to 2016","volume":"24","author":"Sonden","year":"2019","journal-title":"Euro Surveill"},{"key":"2022040917420268700_CIT0026","doi-asserted-by":"crossref","first-page":"1094","DOI":"10.4269\/ajtmh.20-0186","article-title":"Estimating the proportion of Plasmodium vivax recurrences caused by relapse: a systematic review and meta-analysis","volume":"103","author":"Commons","year":"2020","journal-title":"Am J Trop Med Hyg"},{"key":"2022040917420268700_CIT0027","doi-asserted-by":"crossref","first-page":"e1001891","DOI":"10.1371\/journal.pmed.1001891","article-title":"Strategies for understanding and reducing the Plasmodium vivax and Plasmodium ovale hypnozoite reservoir in Papua New Guinean children: a randomised placebo-controlled trial and mathematical model","volume":"12","author":"Robinson","year":"2015","journal-title":"PLoS Med"},{"key":"2022040917420268700_CIT0028","doi-asserted-by":"crossref","first-page":"78","DOI":"10.1186\/s12936-018-2226-4","article-title":"Molecular evidence for relapse of an imported Plasmodium ovale wallikeri infection","volume":"17","author":"Veletzky","year":"2018","journal-title":"Malar J"},{"key":"2022040917420268700_CIT0029","doi-asserted-by":"crossref","first-page":"2119","DOI":"10.1093\/cid\/ciz131","article-title":"Prospective clinical and molecular evaluation of potential Plasmodium ovale curtisi and wallikeri relapses in a high-transmission setting","volume":"69","author":"Groger","year":"2019","journal-title":"Clin Infect Dis"},{"key":"2022040917420268700_CIT0030","first-page":"347","article-title":"Late relapse of imported Plasmodium ovale malaria: a case report","volume":"93","author":"Siala","year":"2015","journal-title":"Tunis Med"},{"key":"2022040917420268700_CIT0031","first-page":"CD004389","article-title":"Primaquine for preventing relapse in people with Plasmodium vivax malaria treated with chloroquine","volume":"10","author":"Galappaththy","year":"2013","journal-title":"Cochrane Database Syst Rev"},{"key":"2022040917420268700_CIT0032","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1186\/s12916-018-1204-6","article-title":"Geographical and temporal trends and seasonal relapse in Plasmodium ovale spp. and Plasmodium malariae infections imported to the UK between 1987 and 2015","volume":"16","author":"Nabarro","year":"2018","journal-title":"BMC Med"},{"key":"2022040917420268700_CIT0033","doi-asserted-by":"crossref","first-page":"e0006230","DOI":"10.1371\/journal.pntd.0006230","article-title":"Use of primaquine and glucose-6-phosphate dehydrogenase deficiency testing: divergent policies and practices in malaria endemic countries","volume":"12","author":"Recht","year":"2018","journal-title":"PLoS Negl Trop Dis"},{"key":"2022040917420268700_CIT0034","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1186\/s40794-017-0049-x","article-title":"Management of Plasmodium vivax risk and illness in travelers","volume":"3","author":"Baird","year":"2017","journal-title":"Trop Dis Travel Med Vaccines"},{"key":"2022040917420268700_CIT0035","doi-asserted-by":"crossref","first-page":"929","DOI":"10.1016\/S0140-6736(19)31285-1","article-title":"Short-course primaquine for the radical cure of Plasmodium vivax malaria: a multicentre, randomised, placebo-controlled non-inferiority trial","volume":"394","author":"Taylor","year":"2019","journal-title":"Lancet"},{"key":"2022040917420268700_CIT0036","first-page":"CD012656","article-title":"Primaquine at alternative dosing schedules for preventing relapse in people with Plasmodium vivax malaria","volume":"7","author":"Milligan","year":"2019","journal-title":"Cochrane Database Syst Rev"},{"key":"2022040917420268700_CIT0037","doi-asserted-by":"crossref","first-page":"104","DOI":"10.1186\/s12936-019-2731-0","article-title":"Accuracy of malaria diagnosis by clinical laboratories in Belgium","volume":"18","author":"Loomans","year":"2019","journal-title":"Malar J"}],"container-title":["Clinical Infectious Diseases"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/academic.oup.com\/cid\/advance-article-pdf\/doi\/10.1093\/cid\/ciab610\/39716069\/ciab610.pdf","content-type":"application\/pdf","content-version":"am","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/cid\/article-pdf\/74\/7\/1199\/43350189\/ciab610.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/cid\/article-pdf\/74\/7\/1199\/43350189\/ciab610.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,9]],"date-time":"2022-04-09T17:42:47Z","timestamp":1649526167000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/cid\/article\/74\/7\/1199\/6314296"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,7,3]]},"references-count":37,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2021,7,3]]},"published-print":{"date-parts":[[2022,4,9]]}},"URL":"https:\/\/doi.org\/10.1093\/cid\/ciab610","relation":{},"ISSN":["1058-4838","1537-6591"],"issn-type":[{"value":"1058-4838","type":"print"},{"value":"1537-6591","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2022,4,1]]},"published":{"date-parts":[[2021,7,3]]}}}