• Eleonora Kaneva National Centre of Infectious and Parasitic Diseases Author
  • Nina Tsvetkova National Centre of Infectious and Parasitic Diseases Author
  • Assoc. Prof. Iskra Rainova National Centre of Infectious and Parasitic Diseases Author



Toxocara spp., PCR, ITS-2, molecular identification


The ascaridoid nematodes of dogs and cats T. canis and T. cati are with widespread distribu-tion and causative agents of a disease in human and animals named Toxocariasis. Human dis-ease has several clinical forms with different clinical manifestation such as visceral, ocular, neurotoxocariasis and covert toxocariasis. The morphological methods used to differentiate the two species, especially to identify eggs or larvae, can lead to inaccurate diagnosis. This requires the use of more reliable methods, such as PCR, for identification of Toxocara species.

The aim of our research is to develop in our conditions a PCR method for species identification of Toxocara and to determine its applicability on different stages of parasites.

The method used by Khademvatan et al. (2013), we performed with some modifications in different forms of Toxocara - eggs, larvae and adult parasites. We used species-specific oligonucleotide primers from the ITS2 gene sequence of the ribosomal DNA - Tcan1/NC2 for T. canis and Tcat1/NC2 for T. cati.

The presence of a band with a size of 380 bp, specific for T. canis, was found for all stages of the studied parasite.

The described method will allow species differentiation of Toxocariasis causative agents and improve the diagnosis of the disease, as well as determine the actual spread and reservoirs of these parasites.


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Author Biographies

  • Eleonora Kaneva, National Centre of Infectious and Parasitic Diseases

    Department of Parasitology and Tropical Medicine

  • Nina Tsvetkova, National Centre of Infectious and Parasitic Diseases

    Department of Parasitology and Tropical Medicine

  • Assoc. Prof. Iskra Rainova, National Centre of Infectious and Parasitic Diseases

    Department of Parasitology and Tropical Medicine


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How to Cite

Kaneva, E.; Tsvetkova, N.; Raynova, I. APPLICATION OF PCR METHOD FOR DETECTION AND SPECIES IDENTIFICATION OF TOXOCARA SPP. Probl Infect Parasit Dis 2020, 48 (3), 26-30.

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