{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T11:13:23Z","timestamp":1776942803761,"version":"3.51.4"},"reference-count":42,"publisher":"American Society of Tropical Medicine and Hygiene","issue":"4","license":[{"start":{"date-parts":[[2023,10,4]],"date-time":"2023-10-04T00:00:00Z","timestamp":1696377600000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2023,10,4]]},"abstract":"<jats:title>ABSTRACT.<\/jats:title>\n<jats:p>To implement the appropriate strategies for scale-up interventions to eliminate onchocerciasis without severe adverse events, clinical and biological factors associated with loiasis were analyzed in onchocerciasis-endemic areas. Blood was collected from volunteers after examination by a physician. Detection of microfilariae and measurement of Ov16 IgG4 were performed using direct microscopic examination of blood and onchocerciasis rapid test detection, respectively. Areas with sporadic, hypoendemic, and hyperendemic onchocerciasis endemicity were found. Participants with microfilaremia were considered microfilaremic, and those without microfilaremia were seen as amicrofilaremic. Of the 471 study participants, 40.5% (<jats:italic>n<\/jats:italic>\u2009=\u2009191) had microfilariae. Among them, <jats:italic>Mansonella <\/jats:italic>spp. was the most common (78.2%, <jats:italic>n<\/jats:italic>\u2009=\u2009147), followed by <jats:italic>Loa loa<\/jats:italic> (41.4%, <jats:italic>n<\/jats:italic>\u2009=\u200979). The association between the two species represented 18.3% (<jats:italic>n<\/jats:italic>\u2009=\u200935). The specific immunoglobulins of <jats:italic>Onchocerca volvulus<\/jats:italic> were detected in 24.2% of participants (<jats:italic>n<\/jats:italic>\u2009=\u200987\/359). Overall prevalence of <jats:italic>L. loa<\/jats:italic> was 16.8%. Hypermicrofilaremia was found in 3% (<jats:italic>N<\/jats:italic>\u2009=\u200914), and one participant had more than 30,000 microfilaremiae per milliliter. The frequency of <jats:italic>L. loa<\/jats:italic> did not vary according to the level of onchocerciasis transmission. Pruritus was the most common clinical sign (60.5%, <jats:italic>n<\/jats:italic>\u2009=\u2009285) reported, mainly in microfilaremic participants (72.2%, <jats:italic>n<\/jats:italic>\u2009=\u2009138\/191). The prevalence of <jats:italic>L. loa<\/jats:italic> microfilaria in the study population was below the threshold at risk for the occurrence of serious side effects due to ivermectin. Clinical manifestations frequently observed could be exacerbated by microfilaremia in areas where onchocerciasis transmission is high.<\/jats:p>","DOI":"10.4269\/ajtmh.22-0558","type":"journal-article","created":{"date-parts":[[2023,6,20]],"date-time":"2023-06-20T13:43:35Z","timestamp":1687268615000},"page":"850-857","source":"Crossref","is-referenced-by-count":6,"title":["Sociodemographics, Clinical Factors, and Biological Factors Associated with Loiasis in Endemic Onchocerciasis Areas in Southern Gabon"],"prefix":"10.4269","volume":"109","author":[{"given":"Reinne","family":"Moutongo Mouandza","sequence":"first","affiliation":[{"name":"Department of Parasitology-Mycology and Tropical Medicine, Faculty of Medicine, Universit\u00e9 des Sciences de la Sant\u00e9, Libreville, Gabon"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jean Romain","family":"Mourou","sequence":"additional","affiliation":[{"name":"Department of Parasitology-Mycology and Tropical Medicine, Faculty of Medicine, Universit\u00e9 des Sciences de la Sant\u00e9, Libreville, Gabon"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bridy","family":"Moutombi Ditombi","sequence":"additional","affiliation":[{"name":"Department of Parasitology-Mycology and Tropical Medicine, Faculty of Medicine, Universit\u00e9 des Sciences de la Sant\u00e9, Libreville, Gabon"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hadry","family":"Roger Sibi Matotou","sequence":"additional","affiliation":[{"name":"Department of Parasitology-Mycology and Tropical Medicine, Faculty of Medicine, Universit\u00e9 des Sciences de la Sant\u00e9, Libreville, Gabon"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bernadette","family":"Ekomi","sequence":"additional","affiliation":[{"name":"Department of Parasitology-Mycology and Tropical Medicine, Faculty of Medicine, Universit\u00e9 des Sciences de la Sant\u00e9, Libreville, Gabon"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marielle Karine","family":"Bouyou-Akotet","sequence":"additional","affiliation":[{"name":"Department of Parasitology-Mycology and Tropical Medicine, Faculty of Medicine, Universit\u00e9 des Sciences de la Sant\u00e9, Libreville, Gabon"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Denise Patricia","family":"Mawili-Mboumba","sequence":"additional","affiliation":[{"name":"Department of Parasitology-Mycology and Tropical Medicine, Faculty of Medicine, Universit\u00e9 des Sciences de la Sant\u00e9, Libreville, Gabon"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"2795","reference":[{"key":"b1","series-title":"Ann Trop Med Parasitol","first-page":"715","article-title":"Loiasis","volume":"100","author":"Boussinesq","year":"2006"},{"key":"b2","series-title":"J Infect Dis","first-page":"1318","article-title":"Loiasis in endemic and nonendemic populations: immunologically mediated 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