Epidemiological relevance of dogs for the prevention of Toxoplasma gondii, Neospora caninum and Leptospira spp.

Abstract This study evaluated the seroprevalence of Toxoplasma gondii, Neospora caninum and Leptospira spp. in dogs from Foz do Iguaçu, Paraná, Brazil. Indirect immunofluorescent antibody test was used to detect antibodies anti-T.gondii and anti-N. caninum. Immunoenzymatic assay and microscopic serum agglutination were used for screening antibodies anti-T.gondii and anti-Leptospira spp., respectively. The results were: 67.02% of the samples reactive for T.gondii and 1.38% for N. caninum, both without statistically significant variables. For Leptospira spp. the results indicated seroprevalence of 23.11%. The analysis of the variables without distinction of serovar showed association for intrinsic characteristics as breed, age, nutritional status and dog category. The extrinsic variables as city region and access to the street presented association (p<0.05). The most prevalent serovars were: Canicola 59.47%; Bratislava 13.07% and Butembo 15.68%. Variables that make up the adjusted multiple analysis model using Leptospira spp. were: age, breed and nutritional status; serovar Canicola, sex, nutritional status and area (p<0.05); serovar Bratislava, lymphadenomegaly and presence of fleas (p<0.05). Given the results obtained, dogs can be used as sentinels for toxoplasmosis and leptospirosis in Foz do Iguaçu and other cities with similar outcomes. In addition, preventive measures should be taken by health authorities because they are zoonoses and humans are also at risk.

摘要 本研究针对巴西巴拉那州伊瓜苏港的犬只，开展了刚地弓形虫（Toxoplasma gondii）、新孢子虫（Neospora caninum）与钩端螺旋体属（Leptospira spp.）的血清阳性率调查。本研究采用间接免疫荧光抗体试验（indirect immunofluorescent antibody test）检测抗刚地弓形虫与抗新孢子虫抗体；分别采用免疫酶试验（immunoenzymatic assay）与显微镜血清凝集试验（microscopic serum agglutination）筛查抗刚地弓形虫抗体与抗钩端螺旋体属抗体。结果显示：67.02%的样本呈刚地弓形虫反应阳性，1.38%的样本呈新孢子虫反应阳性，两项指标均未发现具有统计学意义的关联变量。针对钩端螺旋体属的调查结果显示其血清阳性率为23.11%。不区分血清型的变量分析表明，犬只的品种、年龄、营养状况及犬只类别等内在特征与感染存在关联；城市区域与可自由出入街道等外在变量同样与感染存在统计学关联（p<0.05）。本次检出的优势血清型依次为：犬型（Canicola）59.47%、布拉迪斯拉发型（Bratislava）13.07%与布滕博型（Butembo）15.68%。针对钩端螺旋体属的校正多变量分析模型纳入的变量包括：年龄、品种与营养状况；针对犬型血清型的分析纳入性别、营养状况与采样区域（p<0.05）；针对布拉迪斯拉发型血清型的分析则纳入淋巴结肿大与跳蚤寄生情况（p<0.05）。基于本研究结果，伊瓜苏港及其他同类地区的犬只可作为弓形虫病（toxoplasmosis）与钩端螺旋体病（leptospirosis）的哨兵动物。此外，由于这两种疾病均为人畜共患病（zoonoses），人类同样面临感染风险，当地卫生主管部门应采取相应预防措施。