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Identifying wildlife reservoirs of neglected taeniid tapeworms: Non-invasive diagnosis of endemic Taenia serialis infection in a wild primate population. PLoS Negl Trop Dis 2017; 11:e0005709. [PMID: 28704366 PMCID: PMC5526605 DOI: 10.1371/journal.pntd.0005709] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 07/25/2017] [Accepted: 06/12/2017] [Indexed: 11/19/2022] Open
Abstract
Despite the global distribution and public health consequences of Taenia tapeworms, the life cycles of taeniids infecting wildlife hosts remain largely undescribed. The larval stage of Taenia serialis commonly parasitizes rodents and lagomorphs, but has been reported in a wide range of hosts that includes geladas (Theropithecus gelada), primates endemic to Ethiopia. Geladas exhibit protuberant larval cysts indicative of advanced T. serialis infection that are associated with high mortality. However, non-protuberant larvae can develop in deep tissue or the abdominal cavity, leading to underestimates of prevalence based solely on observable cysts. We adapted a non-invasive monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) to detect circulating Taenia spp. antigen in dried gelada urine. Analysis revealed that this assay was highly accurate in detecting Taenia antigen, with 98.4% specificity, 98.5% sensitivity, and an area under the curve of 0.99. We used this assay to investigate the prevalence of T. serialis infection in a wild gelada population, finding that infection is substantially more widespread than the occurrence of visible T. serialis cysts (16.4% tested positive at least once, while only 6% of the same population exhibited cysts). We examined whether age or sex predicted T. serialis infection as indicated by external cysts and antigen presence. Contrary to the female-bias observed in many Taenia-host systems, we found no significant sex bias in either cyst presence or antigen presence. Age, on the other hand, predicted cyst presence (older individuals were more likely to show cysts) but not antigen presence. We interpret this finding to indicate that T. serialis may infect individuals early in life but only result in visible disease later in life. This is the first application of an antigen ELISA to the study of larval Taenia infection in wildlife, opening the doors to the identification and description of infection dynamics in reservoir populations. Although tapeworm parasites of the genus Taenia are globally distributed and inflict enormous socioeconomic and health costs on their hosts, which include humans, little is known about taeniid tapeworms that infect wildlife. This gap in knowledge prevents an assessment of the potential for these parasites to infect humans and production animals and is largely due to the difficulty of conducting standard diagnostic tests on wildlife. To address this gap, we adapted a standard diagnostic assay to be used with dried urine samples. We used urine from geladas, primates endemic to Ethiopia, which are frequently infected with the larval stage of a taeniid tapeworm and exhibit protuberant cysts during advanced infection. The use of this diagnostic test in a wild gelada population allowed us to detect that individuals can be infected without exhibiting observable cysts, and that some individuals may control infection in its early stages. This tool provides information about how a neglected tapeworm functions in a wildlife system and opens the door to the non-invasive identification of tapeworm reservoir hosts that may threaten humans.
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Braae UC, Saarnak CFL, Mukaratirwa S, Devleesschauwer B, Magnussen P, Johansen MV. Taenia solium taeniosis/cysticercosis and the co-distribution with schistosomiasis in Africa. Parasit Vectors 2015; 8:323. [PMID: 26065414 PMCID: PMC4465723 DOI: 10.1186/s13071-015-0938-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 06/05/2015] [Indexed: 12/03/2022] Open
Abstract
Background This study aimed to map the distribution of Taenia solium taeniosis/cysticercosis and the co-distribution with schistosomiasis in Africa. These two major neglected tropical diseases are presumed to be widely distributed in Africa, but currently the level of co-distribution is unclear. Methods A literature search on T. solium taeniosis/cysticercosis was performed to compile all known studies on the presence of T. solium and apparent prevalence of taeniosis and porcine cysticercosis in Africa. Studies were geo-referenced using an online gazetteer. A Bayesian framework was used to combine the epidemiological data on the apparent prevalence with external information on test characteristics to estimate informed district-level prevalence of taeniosis and porcine cysticercosis. Districts with T. solium taeniosis/cysticercosis presence were cross-referenced with the Global Neglected Tropical Diseases Database for schistosomiasis presence. Results The search strategies identified 141 reports of T. solium in Africa from 1985 to 2014 from a total of 476 districts in 29 countries, 20 with porcine cysticercosis, 22 with human cysticercosis, and 16 with taeniosis, in addition to 2 countries identified from OIE reports. All 31 countries were considered, on national scale, to have co-distribution with schistosomiasis. Presence of both parasites was confirmed in 124 districts in 17 countries. The informed prevalence of taeniosis and porcine cysticercosis were estimated for 14 and 41 districts in 10 and 13 countries, respectively. Conclusions With the paucity of data, T. solium infection is grossly under-reported and expected to be more widespread than this study suggests. In areas where co-distribution occurs there is a need for increased emphasis on evaluation of integrated intervention approaches for these two helminth infections and allocation of resources for evaluating the extent of adverse effects caused by mass drug administration. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-0938-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Uffe Christian Braae
- Department of Veterinary Disease Biology, Section for Parasitology and Aquatic Diseases, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1870, Frederiksberg, Denmark.
| | - Christopher F L Saarnak
- Department of Veterinary Disease Biology, Section for Parasitology and Aquatic Diseases, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1870, Frederiksberg, Denmark.
| | - Samson Mukaratirwa
- School of Life Sciences, University of KwaZulu-Natal, Durban, South Africa.
| | - Brecht Devleesschauwer
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, 9820, Merelbeke, Belgium. .,Institute of Health and Society (IRSS), Université catholique de Louvain, 1200, Brussels, Belgium.
| | - Pascal Magnussen
- Department of Veterinary Disease Biology, Section for Parasitology and Aquatic Diseases, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1870, Frederiksberg, Denmark. .,Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1353, Copenhagen, Denmark.
| | - Maria Vang Johansen
- Department of Veterinary Disease Biology, Section for Parasitology and Aquatic Diseases, Faculty of Health and Medical Sciences, University of Copenhagen, DK-1870, Frederiksberg, Denmark.
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Mwape KE, Phiri IK, Praet N, Dorny P, Muma JB, Zulu G, Speybroeck N, Gabriël S. Study and ranking of determinants of Taenia solium infections by classification tree models. Am J Trop Med Hyg 2014; 92:56-63. [PMID: 25404073 DOI: 10.4269/ajtmh.13-0593] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Taenia solium taeniasis/cysticercosis is an important public health problem occurring mainly in developing countries. This work aimed to study the determinants of human T. solium infections in the Eastern province of Zambia and rank them in order of importance. A household (HH)-level questionnaire was administered to 680 HHs from 53 villages in two rural districts and the taeniasis and cysticercosis status determined. A classification tree model (CART) was used to define the relative importance and interactions between different predictor variables in their effect on taeniasis and cysticercosis. The Katete study area had a significantly higher taeniasis and cysticercosis prevalence than the Petauke area. The CART analysis for Katete showed that the most important determinant for cysticercosis infections was the number of HH inhabitants (6 to 10) and for taeniasis was the number of HH inhabitants > 6. The most important determinant in Petauke for cysticercosis was the age of head of household > 32 years and for taeniasis it was age < 55 years. The CART analysis showed that the most important determinant for both taeniasis and cysticercosis infections was the number of HH inhabitants (6 to 10) in Katete district and age in Petauke. The results suggest that control measures should target HHs with a high number of inhabitants and older individuals.
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Affiliation(s)
- Kabemba E Mwape
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia; Department of Veterinary Tropical Diseases, Faculty of Veterinary Sciences, University of Pretoria, Pretoria, South Africa; Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium; Laboratory of Veterinary Parasitology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium; Department of Disease Control, School of Veterinary Medicine, University of Zambia, Zambia; Petauke District Hospital, Petauke, Zambia; Institute of Health and Society, Université Catholique de Louvain, Brussels, Belgium
| | - Isaac K Phiri
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia; Department of Veterinary Tropical Diseases, Faculty of Veterinary Sciences, University of Pretoria, Pretoria, South Africa; Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium; Laboratory of Veterinary Parasitology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium; Department of Disease Control, School of Veterinary Medicine, University of Zambia, Zambia; Petauke District Hospital, Petauke, Zambia; Institute of Health and Society, Université Catholique de Louvain, Brussels, Belgium
| | - Nicolas Praet
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia; Department of Veterinary Tropical Diseases, Faculty of Veterinary Sciences, University of Pretoria, Pretoria, South Africa; Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium; Laboratory of Veterinary Parasitology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium; Department of Disease Control, School of Veterinary Medicine, University of Zambia, Zambia; Petauke District Hospital, Petauke, Zambia; Institute of Health and Society, Université Catholique de Louvain, Brussels, Belgium
| | - Pierre Dorny
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia; Department of Veterinary Tropical Diseases, Faculty of Veterinary Sciences, University of Pretoria, Pretoria, South Africa; Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium; Laboratory of Veterinary Parasitology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium; Department of Disease Control, School of Veterinary Medicine, University of Zambia, Zambia; Petauke District Hospital, Petauke, Zambia; Institute of Health and Society, Université Catholique de Louvain, Brussels, Belgium
| | - John B Muma
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia; Department of Veterinary Tropical Diseases, Faculty of Veterinary Sciences, University of Pretoria, Pretoria, South Africa; Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium; Laboratory of Veterinary Parasitology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium; Department of Disease Control, School of Veterinary Medicine, University of Zambia, Zambia; Petauke District Hospital, Petauke, Zambia; Institute of Health and Society, Université Catholique de Louvain, Brussels, Belgium
| | - Gideon Zulu
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia; Department of Veterinary Tropical Diseases, Faculty of Veterinary Sciences, University of Pretoria, Pretoria, South Africa; Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium; Laboratory of Veterinary Parasitology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium; Department of Disease Control, School of Veterinary Medicine, University of Zambia, Zambia; Petauke District Hospital, Petauke, Zambia; Institute of Health and Society, Université Catholique de Louvain, Brussels, Belgium
| | - Niko Speybroeck
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia; Department of Veterinary Tropical Diseases, Faculty of Veterinary Sciences, University of Pretoria, Pretoria, South Africa; Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium; Laboratory of Veterinary Parasitology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium; Department of Disease Control, School of Veterinary Medicine, University of Zambia, Zambia; Petauke District Hospital, Petauke, Zambia; Institute of Health and Society, Université Catholique de Louvain, Brussels, Belgium
| | - Sarah Gabriël
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia; Department of Veterinary Tropical Diseases, Faculty of Veterinary Sciences, University of Pretoria, Pretoria, South Africa; Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium; Laboratory of Veterinary Parasitology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium; Department of Disease Control, School of Veterinary Medicine, University of Zambia, Zambia; Petauke District Hospital, Petauke, Zambia; Institute of Health and Society, Université Catholique de Louvain, Brussels, Belgium
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Mwape KE, Phiri IK, Praet N, Muma JB, Zulu G, Van den Bossche P, de Deken R, Speybroeck N, Dorny P, Gabriël S. Taenia solium Infections in a rural area of Eastern Zambia-a community based study. PLoS Negl Trop Dis 2012; 6:e1594. [PMID: 22479664 PMCID: PMC3313923 DOI: 10.1371/journal.pntd.0001594] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 02/24/2012] [Indexed: 11/18/2022] Open
Abstract
Background Taenia solium taeniosis/cysticercosis is a parasitic infection occurring in many developing countries. Data on the status of human infections in Zambia is largely lacking. We conducted a community-based study in Eastern Zambia to determine the prevalence of human taeniosis and cysticercosis in a rural community. Methods and Findings Stool and serum samples were collected from willing participants. Geographical references of the participants' households were determined and household questionnaires administered. Taeniosis was diagnosed in stool samples by coprology and by the polyclonal antibody-based copro-antigen enzyme-linked immunosorbent assay (copro-Ag ELISA), while cysticercosis was diagnosed in serum by the B158/B60 monoclonal antibody-based antigen ELISA (sero-Ag ELISA). Identification of the collected tapeworm after niclosamide treatment and purgation was done using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). A total of 255 households from 20 villages participated in the study, 718 stool and 708 serum samples were collected and examined. Forty-five faecal samples (6.3%) were found positive for taeniosis on copro-Ag ELISA while circulating cysticercus antigen was detected in 5.8% (41/708) individuals. The tapeworm recovered from one of the cases was confirmed to be T. solium on PCR-RFLP. Seropositivity (cysticercosis) was significantly positively related to age (p = 0.00) and to copro-Ag positivity (taeniosis) (p = 0.03) but not to gender. Change point analysis revealed that the frequency of cysticercus antigens increased significantly in individuals above the age of 30. Copro-Ag positivity was not related to age or gender. The following risk factors were noted to be present in the study community: free-range pig husbandry system and poor sanitation with 47.8% of the households visited lacking latrines. Conclusions This study has recorded high taeniosis and cysticercosis prevalences and identified the need for further studies on transmission dynamics and impact of the disease on the local people. Taenia solium taeniosis/cysticercosis is a zoonotic infection endemic in many developing countries, with humans as the definitive host (taeniosis) and pigs and humans as the intermediate hosts (cysticercosis). When humans act as the intermediate host, the result can be neurocysticercosis, which is associated with acquired epilepsy, considerable morbidity and even mortality. In Africa, most studies have been carried out in pigs with little or no data in humans available. In this human study, conducted in a rural community in Eastern Zambia, prevalences for taeniosis and cysticercosis were determined at 6.3% and 5.8% respectively, indicating the hyperendemicity of the area. Cysticercosis infection was strongly related with age, with a significant increase in prevalence occurring in individuals from the age of 30 onward. A collected tapeworm was confirmed to be T. solium. Risk factors associated with the transmission and maintenance of the parasite such as free roaming pigs, households without latrines, backyard slaughter of pigs without inspection and consumption of undercooked pork were also present. The findings of this work have identified the need for further research in the transmission dynamics and the burden that this infection has on the resources of poor local people.
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Affiliation(s)
- Kabemba E. Mwape
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Isaac K. Phiri
- Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Nicolas Praet
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - John B. Muma
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | | | | | - Reginald de Deken
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Niko Speybroeck
- Institute of Health and Society, Université Catholique de Louvain, Brussels, Belgium
| | - Pierre Dorny
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Laboratory of Parasitology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Sarah Gabriël
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- * E-mail:
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