ORIGINAL ARTICLE Trans R Soc Trop Med Hyg 2018; 00:1–6 doi:10.1093/trstmh/try083 Toxoplasma gondii: seroprevalence and associated risk factors among preschool-aged children in Osun State, Nigeria Oluyomi A. Sowemimo a,b , Tsung-Han Wu c , Yueh-Lun Lee d , Samuel O. Asaolu a , Ting-Wu Chuang e , Olaoluwa P. Akinwale f , Bolaji O. Badejoko g , Vincent P. Gyang f , Timothy Nwafor f , Emmanuel Henry f and Chia-Kwung Fan e,h, * a Department of Zoology, Obafemi Awolowo University, Ile-Ife, Osun State; b Department of Zoology, University of Lagos, Akoka, Lagos State, Nigeria; c Department of Pulmonary Medicine, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan; d Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; e Department of Molecular Parasitology and Tropical Diseases, School of Medicine, College of Medicine,Taipei Medical University, Taipei, Taiwan; f Molecular Parasitology Research Laboratory, Department of Public Health, Nigerian Institute of Medical Research, Yaba, Lagos State; g Mother and Child Hospital, Ondo, Ondo State, Nigeria; h Tropical Medicine Division, International PhD Program in Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan *Corresponding author. Tel: +886 926862790; E-mail: tedfan@tmu.edu.tw Received 16 March 2018; revised 11 June 2018; editorial decision 6 July 2018; accepted 9 July 2018 Background: Toxoplasma gondii is an ubiquitous apicomplexan parasite, which causes toxoplasmosis in ani- mals and humans worldwide. However, little is known about T. gondii infection among preschool-aged children in Nigeria. Methods: A cross-sectional study of 272 preschool children aged 2.25±1.09 years from four communities (Edunabon, Erin-Ijesha, Ijebu-jesa and Ile-Ife) in Osun State, Nigeria was conducted between January and July 2016, and the demographic data was obtained via questionnaires. Antibody titres against T. gondii of ser- um samples were assessed by ELISA. Results: The overall seroprevalence of T. gondii infection was 6.9% (19/272). There was no significant differ- ence in seroprevalence of T. gondii infection between boys (7.04%; 10/142) and girls (6.92%; 9/130; p=0.97). No associations were found between age, gender, parental educational level, occupation and religion, and T. gondii seropositivity. None showed statistical significance between the risk factors tested after multivariate adjustment; nevertheless, residing in Ijebu-jesa community was shown to be associated with an increased risk of infection (p=0.04). Conclusion: This is the first report of T. gondii infection among preschool children in Nigeria. Prevalence studies such as this could help in the development of strategies for the future for disease prevention and control of T. gondii transmission. Keywords: Nigeria, preschool children, risk factors, seroprevalence, Toxoplasma gondii Introduction Toxoplasmosis is an important parasitic zoonosis caused by the protozoan Toxoplasma gondii, which is widespread in animals and humans worldwide. 1 Felids such as cats are the definitive hosts of T. gondii and the transmission cycle involves a wide var- iety of intermediate hosts, including humans. Humans become infected with T. gondii mainly by: • close contact with the soil or accidentally ingesting T. gondii oocyst excreted in cats faeces in contaminated food or water; • congenitally by transplacental transmission of tachyzoites; 2,3 • by ingestion of tissue cysts in undercooked or raw meat, or visceral organs. 4,5 Most cases of toxoplasmosis are asymptomatic or only show some self-limiting flu-like syndromes. However, the clinical disease is seen in only a few cases, with serious consequences in immuno- compromised people, particularly AIDS patients, human foetuses and newborn children. 6 An infected newborn could manifest symp- toms including cerebral calcifications, hydrocephaly, microcephaly, psychomotoric retardation, deafness, blindness and epilepsy. 3,4 © The Author(s) 2018. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com. 1 of 6 Downloaded from https://academic.oup.com/trstmh/advance-article-abstract/doi/10.1093/trstmh/try083/5076183 by RSTMH Member Access user on 26 October 2018