{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T06:40:39Z","timestamp":1784011239046,"version":"3.55.0"},"update-to":[{"DOI":"10.1371\/journal.pntd.0012868","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2025,2,21]],"date-time":"2025-02-21T00:00:00Z","timestamp":1740096000000}}],"reference-count":18,"publisher":"Public Library of Science (PLoS)","issue":"2","license":[{"start":{"date-parts":[[2025,2,12]],"date-time":"2025-02-12T00:00:00Z","timestamp":1739318400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100019180","name":"HORIZON EUROPE European Research Council","doi-asserted-by":"publisher","award":["949963"],"award-info":[{"award-number":["949963"]}],"id":[{"id":"10.13039\/100019180","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosntds.org"],"crossmark-restriction":false},"short-container-title":["PLoS Negl Trop Dis"],"abstract":"<jats:sec id=\"sec011\">\n<jats:title>Background<\/jats:title>\n<jats:p>Loiasis is endemic in Central Africa. Despite evidence of clinical complications and increased mortality, it remains excluded from the list of neglected tropical diseases. The main manifestations are Calabar swellings (CS), Eyeworm (EW) and non-specific general symptoms such arthralgia and pruritus. We calculated incidence rates for clinical manifestations of loiasis from a 13-month study on clinical manifestations in 991 individuals living in <jats:italic>Loa loa<\/jats:italic>-endemic areas in the Republic of Congo.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec012\">\n<jats:title>Methodology<\/jats:title>\n<jats:p>From September 2022 to September 2023, community health workers collected weekly symptoms from cohort participants. Detailed data on symptom duration, intensity, associated pruritus, and impact on sleep were recorded. Laboratory procedures included thick blood smear for <jats:italic>L. loa<\/jats:italic> microfilaremia measurement, creatininemia measurement and eosinophilia counts. We used multiple failure analysis and frailty models to calculate incidence rates of EW, CS, arthralgia, pruritus and absence from work (AfW) and to analyses factors associated with increased incidence of each symptom. The population-attributable fractions (PAFs) associated with loiasis were also calculated for pruritus, AfW and arthralgia.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec013\">\n<jats:title>Principal findings<\/jats:title>\n<jats:p>Among the studied manifestations, arthralgia had the highest incidence rate at 555.2 cases per 1000 Person-Year (PY), followed by pruritus (332.3 cases\/1000 PY), AfW (298.6\/1000 PY), EW (266.4\/1000 PY), and CS (213.8\/1000 PY). Notably, the incidence rates of CS, pruritus, arthralgia, and AfW were statistically significantly higher in the subgroup of individuals who experienced at least one episode of EW during the follow-up period. EW occurrence is more frequent when microfilaremia is present. The PAFs of AfW, pruritus and arthralgia, associated with loiasis was 18.0% [07.3\u201327.6], 20.8% [11.6\u201329.1] and 12.1% [3.1\u201320.1], respectively.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec014\">\n<jats:title>Conclusion\/significance<\/jats:title>\n<jats:p>This is the first study to provide incidence rates for the clinical manifestations of loiasis. These estimates are crucial for assessing the burden of loiasis. The findings highlight the disease\u2019s impact on quality of life.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pntd.0012868","type":"journal-article","created":{"date-parts":[[2025,2,12]],"date-time":"2025-02-12T18:41:38Z","timestamp":1739385698000},"page":"e0012868","update-policy":"https:\/\/doi.org\/10.1371\/journal.pntd.corrections_policy","source":"Crossref","is-referenced-by-count":4,"title":["Incidence of loiasis clinical manifestations in a rural area of the Republic of Congo: Results from a longitudinal prospective study (the MorLo project)"],"prefix":"10.1371","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4400-5204","authenticated-orcid":true,"given":"J\u00e9r\u00e9my T.","family":"Campillo","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Biam-Miveck","family":"Pakat-Pambou","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bachiratou","family":"Sahm","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S\u00e9bastien D.S.","family":"Pion","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marlhand C.","family":"Hemilembolo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elodie","family":"Lebredonchel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michel","family":"Boussinesq","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fran\u00e7ois","family":"Missamou","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C\u00e9dric B.","family":"Chesnais","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2025,2,12]]},"reference":[{"issue":"3","key":"pntd.0012868.ref001","doi-asserted-by":"crossref","first-page":"e165","DOI":"10.1016\/S1473-3099(23)00438-3","article-title":"The African eye worm: current understanding of the epidemiology, clinical disease, and treatment of loiasis","volume":"24","author":"M Ramharter","year":"2023","journal-title":"Lancet Infect Dis"},{"issue":"1","key":"pntd.0012868.ref002","doi-asserted-by":"crossref","first-page":"108","DOI":"10.1016\/S1473-3099(16)30405-4","article-title":"Excess mortality associated with loiasis: a retrospective population-based cohort study","volume":"17","author":"CB Chesnais","year":"2016","journal-title":"Lancet Infect Dis"},{"issue":"3","key":"pntd.0012868.ref003","doi-asserted-by":"crossref","first-page":"ofad103","DOI":"10.1093\/ofid\/ofad103","article-title":"Excess mortality associated with loiasis: confirmation by a new retrospective cohort study conducted in the Republic of Congo","volume":"10","author":"MC Hemilembolo","year":"2023","journal-title":"Open Forum Infect Dis"},{"issue":"9","key":"pntd.0012868.ref004","doi-asserted-by":"crossref","first-page":"e704","DOI":"10.1016\/S2666-5247(23)00142-8","article-title":"Association between blood Loa loa microfilarial density and proteinuria levels in a rural area of the Republic of Congo (MorLo): a population-based cross-sectional study","volume":"4","author":"JT Campillo","year":"2023","journal-title":"Lancet Microbe"},{"issue":"6","key":"pntd.0012868.ref005","doi-asserted-by":"crossref","first-page":"e0011430","DOI":"10.1371\/journal.pntd.0011430","article-title":"Association between altered cognition and Loa loa microfilaremia: first evidence from a cross-sectional study in a rural area of the Republic of Congo. 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