Document Type : Original Article
Authors
1 Department of Parasitology, Medical Faculty, Zabol University of Medical Sciences, Zabol, Iran
2 Bacteriology & Virology Department, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
Abstract
Background: Hymenolepis nana, the dwarf tapeworm, is the most prevalent human cestode, particularly affecting children in developing countries with poor sanitation. This study used mitochondrial DNA sequencing techniques to investigate the molecular characteristics and genetic diversity of H. nana isolates from human fecal samples in Zabol, Iran.
Methods: In this descriptive cross-sectional study, 374 stool samples were examined using microscopy for H. nana infection. DNA was extracted from microscopically positive samples, and the rrnS-mtDNA(rrnS) gene was amplified using specific primers. PCR products were sequenced and compared to reference sequences in GenBank. Phylogenetic analysis was performed to assess genetic relationships among isolates.
Results: The prevalence of H. nana infection was 3.74% (95% CI: 2.07-6.19%). Seven out of 14 positive samples were successfully sequenced. The rrnS-mtDNA sequences from Zabol isolates showed 99% identity to the reference strain. Phylogenetic analysis revealed high similarity ( > 98%) with H. nana sequences from diverse geographical regions. However, distinct nucleotide polymorphisms were observed, indicating regional genetic variations.
Conclusion: This study provides novel insights into the genetic diversity of H. nana in southeast Iran. The observed variations in the mitochondrial genome suggest potential adaptations to local environments or hosts. These findings contribute to our understanding of H. nana epidemiology and may inform the development of targeted molecular diagnostics and control strategies for this widespread cestodiasis.
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