Open Access Research

Toxoplasma gondii infection: relationship between seroprevalence and risk factors among primary schoolchildren in the capital areas of Democratic Republic of São Tomé and Príncipe, West Africa

Chia-Kwung Fan1,2*, Lin-Wen Lee3, Chien-Wei Liao1,2, Ying-Chieh Huang1,2, Yueh-Lun Lee3, Yu-Tai Chang4, Ângela dos Santos Ramos José da Costa5, Vilfrido Gil6, Li-Hsing Chi4, Takeshi Nara7, Akiko Tsubouchi7 and Olaoluwa P Akinwale8

Author Affiliations

1 Department of Parasitology, College of Medicine, Taipei Medical University, 250 Wuxing St, Taipei, 11031, Taiwan

2 Center for International Tropical Medicine, College of Medicine, Taipei Medical University, 250 Wuxing St, Taipei, 11031, Taiwan

3 Department of Microbiology and Immunology, College of Medicine, Taipei Medical University, 250 Wuxing St, Taipei, 11031, Taiwan

4 Taiwan Medical Mission in São Tomé, São Tomé, C.P. 839, Democratic Republic of São Tomé and Príncipe

5 Ministry of Health and Social Affairs, São Tomé, C.P. 23, Democratic Republic of São Tomé and Príncipe

6 National Global Fund Program in Sao Tome, Sao Tome, C.P. 23, Democratic Republic of São Tomé and Príncipe

7 Department of Molecular and Cellular Parasitology, Juntendo University School of Medicine, Tokyo, 113-8421, Japan

8 Nigerian Institute of Medical Research, Lagos, P.M.B 2013, Nigeria

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Parasites & Vectors 2012, 5:141 doi:10.1186/1756-3305-5-141

Published: 13 July 2012

Abstract

Background

The status of Toxoplasma gondii infection among primary schoolchildren (PSC) of the Democratic Republic of São Tomé and Príncipe (DRSTP), West Africa, remains unknown to date.

Methods

A serologic survey and risk factors associated T. gondii infection among PSC in the DRSTP was assessed by the latex agglutination (LA) test and a questionnaire interview including parents’ occupation, various uncomfortable symptoms, histories of eating raw or undercooked food, drinking unboiled water, and raising pets, was conducted in October 2010. Schoolchildren from 4 primary schools located in the capital areas were selected, in total 255 serum samples were obtained by venipuncture, of which 123 serum samples were obtained from boys (9.8 ± 1.4 yrs) and 132 serum samples were obtained from girls (9.7 ± 1.3 yrs).

Results

The overall seroprevalence of T. gondii infection was 63.1% (161/255). No significant gender difference in seroprevalence was found between boys (62.6%, 77/123) and girls (63.6%, 84/132) (p = 0.9). The older age group of 10 years had insignificantly higher seroprevalence (69.9%, 58/83) than that of the younger age group of 8 year olds (67.7%, 21/31) (p = 0.8). It was noteworthy that the majority of seropositive PSC (75.8%, 122/161) had high LA titers of ≥1: 1024, indirectly indicating acute or repeated Toxoplasma infection. Parents whose jobs were non-skilled workers (73.1%) showed significantly higher seroprevalence than that of semiskilled- (53.9%) or skilled workers (48.8%) (p < 0.05). Children who had a history of raising cats also showed significantly higher seroprevalence than those who did not (p < 0.001).

Children who claimed to have had recent ocular manifestation or headache, i.e. within 1 month, seemed to have insignificantly higher seroprevalence than those who did not (p > 0.05).

Conclusions

Parents’ educational level and cats kept indoors seemed to be the high risk factors for PSC in acquisition of T. gondii infection. While, ocular manifestation and/or headache of PSC should be checked for the possibility of being T. gondii elicited. Measures such as improving environmental hygiene and intensive educational intervention to both PSC and their parents should be performed immediately so as to reduce T. gondii infection of DRSTP inhabitants including PSC and adults.

Keywords:
Seroepidemiology; Toxoplasma gondii; Primary schoolchildren; Democratic Republic of São Tomé and Príncipe; West Africa