Morphological and Molecular Analysis of Enterobius vermicularis with Syphacia spp

Syphacia (rodent pinworm), a common nematode in the colon of rodents, has rarely been reported in humans. The morphological identification of some pinworm species is difficult, especially in those cases where only fragments of worms are recovered. We aimed to identify isolates of Syphacia spp. in rodents using morphological and molecular approaches, and to compare them with human Enterobius vermicularis.

This study was carried out on 10 adult Syphacia worms collected from BALB/c mice and five adult Enterobius vermicularis from humans. Morphological features using existing keys and PCR-sequencing of ITS1 and 5.8s regions were applied to identify Syphacia spp., and its comparison with E. vermicularis.

The total length of esophagus, the length and width of esophageal bulb, and the length and width of the right and left cephalic alae of E. vermicularis were larger than Syphacia. These parameters demonstrated significant morphological differences between E. vermicularis and Syphacia. PCR successfully produced amplicons of approximately 414 bp for Syphacia and 473 bp for E. vermicularis. The molecular method identified the Oxyurid nematodes isolated from BALB/c mice as Syphacia obvelata. The pairwise comparison revealed no differences in nucleotide sequences among S. obvelata isolates, and the sequences were identical and exhibited 100% homology.

This study demonstrated genetic and morphological differences between E. vermicularis and S. obvelata. Since laboratory mice (Mus musculus) are the specific hosts for S. obvelata, controlling these animals is critical to maintaining public health.