Hassan Mo'awia M, Osman Omran F, El-Raba'a Fathi Ma, Schallig Henk Dfh, Elnaiem Dia-Eldin A
Department of Epidemiology, Tropical Medicine Research Institute, National Centre for Research, Ministry of Science and Technology, PO Box 1304, Khartoum, Sudan.
Parasit Vectors. 2009 Jun 17;2(1):26. doi: 10.1186/1756-3305-2-26.
The study aims to determine the role of domestic dogs in transmission of visceral leishmaniasis in eastern Sudan. A cross-sectional survey was conducted in 10 villages along the River Rahad in eastern Sudan to elucidate the role of domestic dogs (Canis familiaris, Linnaeus, 1758) as a reservoir host of Leishmania donovani. In this study, 87 dogs were screened for infection by Leishmania donovani. Blood and lymph node samples were taken from 87 and 33 dogs respectively and subsequently screened by the Polymerase Chain Reaction (PCR) and Direct Agglutination Test (DAT) test. Additional lymph node smears were processed for microscopy and parasite culture. Host preference of the visceral leishmaniasis (VL) vector in the area, Phlebotomus orientalis, and other sandflies for the Nile rat (Arvicanthis niloticus, E. Geoffrey, 1803), the genet (Genetta genetta, Linnaeus, 1758), the mongoose (Herpeistes ichneumon, Linnaeus, 1758), and the domestic dog were determined by counting numbers of sand flies attracted to CDC traps that were baited by these animals.
DAT on blood samples detected anti-Leishmania antibodies in 6 samples (6.9%). Two out of 87 (2.3%) blood samples tested were PCR positive, giving an amplification product of 560 bp. The two positive samples by PCR were also positive by DAT. However, none of the 33 lymph nodes aspirates were Leishmania positive when screened by microscopy, culture and genus-specific PCR. The dog-baited trap significantly attracted the highest number of P. orientalis and sand fly species (P < 0.001). This was followed by the Egyptian mongoose baited trap and less frequently by the genet baited trap.
It is concluded that the results obtained from host attraction studies indicate that dog is more attractive for P. orientalis than Egyptian mongoose, common genet and Nile rat.
本研究旨在确定家犬在苏丹东部内脏利什曼病传播中的作用。在苏丹东部拉哈德河沿岸的10个村庄进行了一项横断面调查，以阐明家犬（犬属家犬，林奈，1758年）作为杜氏利什曼原虫储存宿主的作用。在本研究中，对87只犬进行了杜氏利什曼原虫感染筛查。分别从87只和33只犬采集血液和淋巴结样本，随后通过聚合酶链反应（PCR）和直接凝集试验（DAT）进行筛查。另外对淋巴结涂片进行显微镜检查和寄生虫培养。通过计数被这些动物诱饵吸引到疾控中心诱捕器上的白蛉数量，确定该地区内脏利什曼病（VL）传播媒介东方白蛉和其他白蛉对尼罗大鼠（非洲沼鼠，E. 杰弗里，1803年）、非洲林狸（非洲林狸，林奈，1758年）、埃及獴（埃及獴，林奈，1758年）和家犬的宿主偏好。
血液样本的DAT检测在6个样本（6.9%）中检测到抗利什曼原虫抗体。87份血液样本中有2份（2.3%）PCR检测呈阳性，扩增产物为560 bp。PCR检测呈阳性的两份样本DAT检测也呈阳性。然而，通过显微镜检查、培养和属特异性PCR筛查，33份淋巴结穿刺液均未发现利什曼原虫阳性。用犬作诱饵的诱捕器吸引到的东方白蛉和白蛉种类数量最多（P < 0.001）。其次是用埃及獴作诱饵的诱捕器，用非洲林狸作诱饵的诱捕器吸引到的白蛉较少。
得出的结论是，宿主吸引力研究结果表明，东方白蛉对家犬的吸引力比对埃及獴、非洲林狸和尼罗大鼠的吸引力更大。
