High prevalence of Toxoplasma gondii oocyst shedding in stray and pet cats (Felis catus) in Virginia, United States

Particle and Fibre Toxicology

Caroline D Wortham¹  Emily L Lilly¹ 

[1] Biology Department, Virginia Military Institute, Lexington, VA 24450, USA

关键词: Toxoplasma gondii;    Prevalence;    PCR;    Parasite;    Oocyst;    Molecular detection;    Felis catus;    Fecal;    Cat;   

Others  :  824597
DOI  :  10.1186/1756-3305-6-266

 received in 2013-05-28, accepted in 2013-08-14,  发布年份 2013

【 摘 要 】

Background

The protozoan Toxoplasma gondii is the causative agent of toxoplasmosis, with complications varying from mental disease to death. While human infection can occur via ingestion of tissue cysts from infected meat, most human infection comes from oocysts. Cats are the only definitive host, and thus shedding of oocysts by cats provides the ultimate source of toxoplasmosis.

Methods

While most studies in the area use seroprevalence to monitor Toxoplasma incidence in cat populations, this provides only a history of infection. This study used PCR detection of oocysts from cat feces to more accurately estimate the numbers of cats producing oocysts and thus posing an active health risk. DNA sequencing was use to confirm the identity of the PCR products.

Results

Of the 49 cats tested, 9 yielded PCR products of the expected size. Six of the nine were determined by sequence analysis to be false positives, while three products were true positives. Overall, 6% of cats examined were found to be actively shedding oocysts.

Conclusions

The incidence of oocyst shedding in the cat population studied was significantly higher than expected and higher than found in most cat populations world-wide. Of equal importance, the primers tested were shown to produce PCR products of multiple sizes and non-target products of expected size. We detected false positives at a higher rate than true positives, emphasizing the need for confirmatory analysis. Further research may produce better protocols for Toxoplasma detection from cat fecal samples.

【 授权许可】

   
2013 Lilly and Wortham; licensee BioMed Central Ltd.

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