INFECTION BY Toxoplasma gondii, Neospora caninum, Leishmania major AND Trypanosoma cruzi IN DOGS FROM THE STATE OF PARÁ

Abstract A serological inquiry was performed to Toxoplasma gondii, Neospora caninum, Leishmania spp. and Trypanosoma cruzi in dogs from the city of Castanhal and Belém, State of Pará, and the association between seropositive animals and factors such as sex, age, access to the streets and provenance of the animals was studied. 269 healthy dogs with different ages, coming from animal shelters, commercial kennels, Zoonosis Control Centre, and domiciles were used. The Indirect immunofluorescence (IIF) reaction was used with plates sensitized with their respective antigens. Among the 263 samples, 100 were reactant, with 38.0% of positivity for Toxplasma gondii, being 16UI and 64UI the prevalent titers, 15.97% of reagent animals for anti-N. caninum antibodies with higher seroprevalence to titers 25UI and 50UI.At the anti-L. major antibodies research, 3.42% were reagent with the titer 40UI being the prevalent. The research of anti-T.cruzi antibodies revealed negativity in all the samples. The provenance and age range variables have been shown as a risk factor to the animals. The animals from the city of Belém presented 2.6 times more changes of infection than the animals from the city of Castanhal. The animals at the age range from three to seven years old presented 2.27 times more changes of being reagent than the dogs with up to three years old. There was no statistical association to the other variables and protozoa researched.

摘要 本研究针对巴西帕拉州卡斯塔纳尔市与贝伦市的犬只，开展了弓形虫（Toxoplasma gondii）、犬新孢子虫（Neospora caninum）、利什曼原虫属（Leishmania spp.）以及克氏锥虫（Trypanosoma cruzi）的血清学调查，并分析了血清学阳性动物与性别、年龄、街头暴露史、动物来源等因素的关联。本研究共纳入269只健康犬只，年龄跨度不一，其来源涵盖动物收容所、商业犬舍、人畜共患病控制中心以及家庭饲养环境。本研究采用间接免疫荧光（Indirect immunofluorescence, IIF）法，使用包被有对应抗原的反应板开展检测。在回收的263份有效样本中，共计100份呈反应阳性：其中弓形虫阳性率为38.0%，优势滴度为16UI与64UI；抗犬新孢子虫抗体阳性率为15.97%，滴度25UI与50UI为主要流行滴度；在抗利什曼原虫（Leishmania major）抗体检测中，阳性率为3.42%，优势滴度为40UI；抗克氏锥虫抗体检测结果则全部为阴性。研究结果显示，动物来源与年龄区间为感染相关的风险因素：贝伦市来源的犬只感染风险为卡斯塔纳尔市犬只的2.6倍；3~7岁年龄组犬只的阳性检出概率为3岁以下犬只的2.27倍。其余变量与本次检测的原虫感染均未显示出统计学关联。