Variables associated with the prevalence of anti-Leishmania spp. antibodies in dogs on the tri-border of Foz do Iguaçu, Paraná, Brazil

Abstract The aim of this study was to investigate the occurrence of anti-Leishmania spp. antibodies in dogs from localities in the city of Foz do Iguaçu, Paraná state, Brazil, on the border with Argentina and Paraguay. Blood samples dogs were collected to perform the following serologic tests: immunochromatographic DPP® rapid test, indirect immunoenzymatic assay (ELISA) and indirect immunofluorescence assay (IFA). In 2012, 285 dogs were analyzed on Argentina border, and in 2013, serum samples from 396 dogs on the border of Paraguay were collected. Using ELISA for screening and IFA for the confirmatory test, the results showed that the antibody prevalence was 1.8% (5/285) on the border of Argentina and 3.0% (12/396) on Paraguay border. When using the DPP® for screening and ELISA as a confirmatory analysis, we observed a seroreagent prevalence in dogs of 2.5% (7/285) on Argentina border and 5.1% (20/396) on Paraguay border. The non-public collection of domestic waste (p= 0.0004) was shown to be associated with leishmaniasis. This study shows the presence of leishmaniasis and suggest the emergence of canine visceral leishmaniasis in state of Paraná due to the confirmed occurrence of seroreactive dogs on Argentina and Paraguay border, which has environmental and geographical characteristics that favor the spread of the parasite.

摘要 本研究旨在探明巴西巴拉那州伊瓜苏港市（毗邻阿根廷与巴拉圭）境内犬只抗利什曼原虫属（Leishmania spp.）抗体的携带情况。研究人员采集犬血液样本，开展三类血清学检测：免疫层析DPP®快速检测试剂、间接酶联免疫吸附试验（ELISA）以及间接免疫荧光试验（IFA）。2012年，研究团队对阿根廷边境区域的285只犬完成检测分析；2013年，于巴拉圭边境区域采集了396份犬血清样本。采用ELISA初筛、IFA确证的检测方案时，阿根廷边境区域的抗体阳性率为1.8%（5/285），巴拉圭边境区域为3.0%（12/396）。若以DPP®作为初筛手段、ELISA开展确证分析，则阿根廷边境区域的犬只血清阳性率为2.5%（7/285），巴拉圭边境区域为5.1%（20/396）。数据分析显示，生活垃圾未规范收集（p=0.0004）与利什曼病存在显著相关性。本研究证实了利什曼病在该区域的存在，并提示巴拉那州或已出现犬内脏利什曼病（canine visceral leishmaniasis）：阿根廷与巴拉圭边境区域已确认存在血清反应阳性的感染犬只，该区域的环境与地理特征均有利于寄生虫的传播扩散。