N'Djetchi Martial Kassi, Ilboudo Hamidou, Koffi Mathurin, Kaboré Jacques, Kaboré Justin Windingoudi, Kaba Dramane, Courtin Fabrice, Coulibaly Bamoro, Fauret Pierre, Kouakou Lingué, Ravel Sophie, Deborggraeve Stijn, Solano Philippe, De Meeûs Thierry, Bucheton Bruno, Jamonneau Vincent
Laboratoire des Interactions Hôte-Microorganisme-Environnement et Evolution, Unité de Formation et de Recherche Environnement, Université Jean Lorougnon Guédé, Daloa, Côte d'Ivoire.
Unité de recherches sur les bases biologiques de la lutte intégrée, Centre International de Recherche-Développement sur l'Elevage en zone Subhumide, Bobo-Dioulasso, Burkina Faso.
PLoS Negl Trop Dis. 2017 Oct 18;11(10):e0005993. doi: 10.1371/journal.pntd.0005993. eCollection 2017 Oct.
Important control efforts have led to a significant reduction of the prevalence of human African trypanosomiasis (HAT) in Côte d'Ivoire, but the disease is still present in several foci. The existence of an animal reservoir of Trypanosoma brucei gambiense may explain disease persistence in these foci where animal breeding is an important source of income but where the prevalence of animal African trypanosomiasis (AAT) is unknown. The aim of this study was to identify the trypanosome species circulating in domestic animals in both Bonon and Sinfra HAT endemic foci.
METHODOLOGY/PRINCIPAL FINDINGS: 552 domestic animals (goats, pigs, cattle and sheep) were included. Blood samples were tested for trypanosomes by microscopic observation, species-specific PCR for T. brucei sl, T. congolense, T. vivax and subspecies-specific PCR for T. b. gambiense and T. b. gambiense immune trypanolysis (TL). Infection rates varied significantly between animal species and were by far the highest in pigs (30%). T. brucei s.l was the most prevalent trypanosome species (13.7%) followed by T. congolense. No T. b. gambiense was identified by PCR while high TL positivity rates were observed using T. b. gambiense specific variants (up to 27.6% for pigs in the Bonon focus).
This study shows that domestic animals are highly infected by trypanosomes in the studied foci. This was particularly true for pigs, possibly due to a higher exposure of these animals to tsetse flies. Whereas T. brucei s.l. was the most prevalent species, discordant results were obtained between PCR and TL regarding T. b. gambiense identification. It is therefore crucial to develop better tools to study the epidemiological role of potential animal reservoir for T. b. gambiense. Our study illustrates the importance of "one health" approaches to reach HAT elimination and contribute to AAT control in the studied foci.
重要的防控措施已使科特迪瓦的人类非洲锥虫病（HAT）患病率大幅降低，但该病仍在多个疫源地存在。布氏冈比亚锥虫动物宿主的存在可能解释了这些疫源地疾病的持续存在，在这些地区，畜牧业是重要的收入来源，但动物非洲锥虫病（AAT）的患病率未知。本研究的目的是确定在博农和辛夫拉HAT流行疫源地的家畜中传播的锥虫种类。
方法/主要发现：纳入了552头家畜（山羊、猪、牛和绵羊）。通过显微镜观察、布氏锥虫复合种、刚果锥虫、活跃锥虫的种特异性PCR以及布氏冈比亚锥虫和布氏罗得西亚锥虫的亚种特异性PCR及免疫锥虫溶解试验（TL）检测血样中的锥虫。不同动物种类的感染率差异显著，猪的感染率最高（30%）。布氏锥虫复合种是最常见的锥虫种类（13.7%），其次是刚果锥虫。PCR未鉴定出布氏冈比亚锥虫，但使用布氏冈比亚锥虫特异性变体观察到较高的TL阳性率（博农疫源地猪的阳性率高达27.6%）。
本研究表明，在所研究疫源地的家畜中锥虫感染率很高。猪尤其如此，可能是因为这些动物更容易接触采采蝇。虽然布氏锥虫复合种是最常见的种类，但在布氏冈比亚锥虫的鉴定上，PCR和TL结果不一致。因此，开发更好的工具来研究潜在动物宿主对布氏冈比亚锥虫的流行病学作用至关重要。我们的研究说明了“同一健康”方法对于实现消除HAT以及在研究疫源地控制AAT的重要性。
