Stray dogs as indicators of Toxoplasma gondii distributed in the environment: the first report across an urban-rural gradient in China

Particle and Fibre Toxicology

Kui-Yang Zheng⁴  Xing-Quan Zhu⁵  Dong-Hui Zhou³  Dong-Hui Wang⁴  Peng Zhang⁴  Ping Zeng¹  Na Shi²  Liang Lv²  Yi-Sheng Liu⁴  Ren-Xian Tang⁴  Cai-Ling Yue³  Lin-Lin Fu⁴  Chao Yan³ 

[1] Department of Epidemiology and Healthy Statistics, Xuzhou Medical College, Xuzhou, Jiangsu Province, China;Grade 2008, the First Department of Clinical Medicine, Xuzhou Medical College, Xuzhou, Jiangsu Province, China;State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, China;Department of Pathogen Biology and Immunology, Laboratory of Infection and Immunity, Xuzhou Medical College, Xuzhou, Jiangsu Province, China;College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang Province, China

关键词: Indicator;    Environment;    Enzyme-linked immunosorbent assay (ELISA);    Stray dog;    Toxoplasma gondii;    Prevalence;   

Others  :  1233659
DOI  :  10.1186/1756-3305-5-5

 received in 2011-12-05, accepted in 2012-01-05,  发布年份 2012

【 摘 要 】

Background

Toxoplasmosis is an important parasitic zoonosis caused by the protozoan Toxoplasma gondii that is distributed world-wide and infects a variety of hosts. However, the prevalence of T. gondii in the environment (such as soil, water and food) is largely unknown. Due to the technical difficulty in oocyst counting directly, an alternative assay using the serologic status of T. gondii in free-living animals, such as stray or free-living dogs, as an indicator, can be used to evaluate environmental contamination indirectly, as they are exposed to the same risk of infection as humans and other animals.

Results

In the present study, 231 stray or free-living dogs across an urban-rural gradient were examined to assess the frequency of T. gondii in the environment. Specific antibodies to T. gondii were found in 93 dogs (40.3%) by enzyme-linked immunosorbent assay (ELISA), and no statistically significant differences were observed in seroprevalences of T. gondii between urban dogs (38.7%) and rural dogs (41%) (p > 0.05).

Conclusions

A high seroprevalence of T. gondii in stray or free-living dogs in the present study indicates that there would be a wide distribution and a constant infection pressure of T. gondii across an urban-rural gradient, and the oocysts of T. gondii in the environment would be an important source of infection for humans and other animals both in urban and rural areas in China.

【 授权许可】

   
2012 Yan et al; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

Figure 3.

Figure 3.

Figure 2.

Figure 3.

【 参考文献 】

• [1]Dubey JP: Toxoplasmosis of animals and humans. In CRC Press Inc. 2nd edition. Boca Raton, New York; 2010.
• [2]Tenter AM, Heckeroth AR, Weiss LM: Toxoplasma gondii: from animals to humans. Int J Parasitol 2000, 30:1217-1258.
• [3]Zhou P, Chen N, Zhang RL, Lin RQ, Zhu XQ: Food-borne parasitic zoonoses in China: perspective for control. Trends Parasitol 2008, 24:190-196.
• [4]Zhou P, Chen Z, Li HL, Zheng H, He S, Lin RQ, Zhu XQ: Toxoplasma gondii infection in humans in China. Parasit Vectors 2011, 4:165. BioMed Central Full Text
• [5]Frenkel JK, Ruiz A, Chinchilla M: Soil survival of Toxoplasma oocysts in Kansas and Costa Rica. Am J Trop Med Hyg 1975, 24:439-443.
• [6]Pereira KS, Franco RM, Leal DA: Transmission of toxoplasmosis (Toxoplasma gondii) by Foods. Adv Food Nutr Res 2010, 60:1-19.
• [7]Boothroyd JC, Grigg ME: Population biology of Toxoplasma gondii and its relevance to human infection: do different strains cause different disease? Curr Opin Microbiol 2002, 5:438-442.
• [8]Munoz-Zanzi CA, Fry P, Lesina B, Hill D: Toxoplasma gondii oocyst-specific antibodies and source of infection. Emerg Infect Dis 2010, 16:1591-1593.
• [9]Dubey JP, Lappin MR, Thulliez P: Diagnosis of induced toxoplasmosis in neonatal cats. J Am Vet Med Assoc 1995, 207:179-185.
• [10]Yilmaz SM, Hopkins SH: Effects of different conditions on duration of infectivity of Toxoplasma gondii oocysts. J Parasitol 1972, 58:938-939.
• [11]Sroka J, Wojcik-Fatla A, Szymanska J, Dutkiewicz J, Zajac V, Zwolinski J: The occurrence of Toxoplasma gondii infection in people and animals from rural environment of Lublin region-estimate of potential role of water as a source of infection. Ann Agric Environ Med 2010, 17:125-132.
• [12]Lehrer EW, Fredebaugh SL, Schooley RL, Mateus-Pinilla NE: Prevalence of antibodies to Toxoplasma gondii in woodchucks across an urban-rural gradient. J Wildl Dis 2010, 46:977-980.
• [13]Miller MA, Gardner IA, Kreuder C, Paradies DM, Worcester KR, Jessup DA, Dodd E, Harris MD, Ames JA, Packham AE, Conrad PA: Coastal freshwater runoff is a risk factor for Toxoplasma gondii infection of southern sea otters (Enhydra lutris nereis). Int J Parasitol 2002, 32:997-1006.
• [14]Dumètre A, Dardé ML: Purification of Toxoplasma gondii oocysts by cesium chloride gradient. J Microbiol Methods 2004, 56:427-430.
• [15]Jones JL, Dubey JP: Waterborne toxoplasmosis-recent developments. Exp Parasitol 2010, 124:10-25.
• [16]Dubey JP, Frenkel JK: Toxoplasmosis of rats: a review, with considerations of their value as an animal model and their possible role in epidemiology. Vet Parasitol 1998, 77:1-32.
• [17]Meireles LR, Galisteo AJ Jr, Pompeu E, Andrade HF Jr: Toxoplasma gondii spreading in an urban area evaluated by seroprevalence in free-living cats and dogs. Trop Med Int Health 2004, 9:876-881.
• [18]Salb AL, Barkema HW, Elkin BT, Thompson R, Whiteside DP, Black SR, Dubey JP, Kutz SJ: Dogs as sources and sentinels of parasites in humans and wildlife, northern Canada. Emerg Infect Dis 2008, 14:60-63.
• [19]Frenkel JK, Lindsay DS, Parker BB, Dobesh M: Dogs as possible mechanical carriers of Toxoplama, and their fur as a source of infection of young children. Int J Infect Dis 2003, 7:292-293.
• [20]Dubey JP: Toxoplasma gondii oocyst survival under defined temperatures. J Parasitol 1998, 84:862-865.
• [21]Afonso E, Thulliez P, Gilot-Fromont E: Local meteorological conditions, dynamics of seroconversion to Toxoplasma gondii in cats (Felis catus) and oocyst burden in a rural environment. Epidemiol Infect 2010, 138:1105-1113.
• [22]Hill D, Dubey JP: Toxoplasma gondii: transmission, diagnosis and prevention. Clin Microbiol Infect 2002, 8:634-640.
• [23]Afonso E, Thulliez P, Gilot-Fromont E: Transmission of Toxoplasma gondii in an urban population of domestic cats (Felis catus). Int J Parasitol 2006, 36:1373-1382.
• [24]Lindsay DS, Dubey JP, Butler JM, Blagburn BL: Experimental tissue cyst induced Toxoplasma gondii infections in dogs. J Eukaryot Microbiol 1996, 43:113S.
• [25]Piergili-Fioretti D: Problems and limitations of conventional and innovative methods for the diagnosis of toxoplasmosis in humans and animals. Parassitologia 2004, 46:177-181. (In Italian)
• [26]Zhang H, Zhou DH, Chen YZ, Lin RQ, Yuan ZG, Song HQ, Li SJ, Zhu XQ: Antibodies to Toxoplasma gondii in stray and household dogs in Guangzhou, China. J Parasitol 2010, 96:671-672.
• [27]Lopes AP, Santos H, Neto F, Rodrigues M, Kwok OC, Dubey JP, Cardoso L: Prevalence of antibodies to Toxoplasma gondii in dogs from northeastern Portugal. J Parasitol 2011, 97:418-420.
• [28]Wu SM, Huang SY, Fu BQ, Liu GY, Chen JX, Chen MX, Yuan ZG, Zhou DH, Weng YB, Zhu XQ, Ye DH: Seroprevalence of Toxoplasma gondii infection in pet dogs in Lanzhou, Northwest China. Parasit Vectors 2011, 4:64. BioMed Central Full Text
• [29]Schares G, Herrmann DC, Beckert A, Schares S, Hosseininejad M, Pantchev N, Globokar Vrhovec M, Conraths FJ: Characterization of a repetitive DNA fragment in Hammondia hammondi and its utility for the specific differentiation of H. hammondi from Toxoplasma gondii by PCR. Mol Cell Probes 2008, 22:244-251.
• [30]Aubert D, Villena I: Detection of Toxoplasma gondii oocysts in water: proposition of a strategy and evaluation in Champagne-Ardenne Region, France. Mem Inst Oswaldo Cruz 2009, 104:290-295.
• [31]Du F, Feng HL, Nie H, Tu P, Zhang QL, Zhou YQ, Zhao JL: Survey on the contamination of Toxoplasma gondii oocysts in the soil of public parks of Wuhan, China. Vet Parasitol, in press.
• [32]He Y, Zhu YP, Yuan ZG, Yin CC, Zhou DH, Lin RQ, Zhu XQ, Weng YB: Comparison of five ELISA kits for detection of anti-Toxoplasma gondii antibodies in experimentally infected swine. Chin Anim Husb Vet Med 2011, 38:218-221. (in Chinese)