Histopathological and molecular evaluation of hydatid cysts according to necropsy findings of 52 equids in Türkiye.

This study focuses on the parasitic cestode, drawing attention to its presence in horses, donkeys, and mules in Türkiye. The research shows that hydatid cysts, potentially harmful to both equine and human health, have been confirmed in these animals through necropsy and further molecular identification.

Introduction and Aim

• This research aimed at investigating the prevalence and molecular characterization of the parasite in equids found in Türkiye. They specifically wanted to identify and further understand the presence of hydatid cysts in these animals. The organism has historically been considered non-zoonotic, meaning it cannot be passed from animals to humans. However, recent studies indicated that this assumption might need a reevaluation.

Methodology

• The research was done retrospectively, examining 52 equine necropsies carried out from 2020 to 2025.
• Upon the identification of hydatid cysts in an Arabian horse and two donkeys, gross and histopathological examinations were performed. The cysts were confirmed to be present in the liver and lungs of these animals.
• Molecular identification of the cysts was conducted using PCR amplification that targeted the mitochondrial cytochrome c oxidase subunit 1 (mt-CO1) gene. Sequence analysis confirmed that all positive samples belonged to the organism.
• The researchers also carried out a Phylogenetic analysis to understand the relationship between the sequences obtained and reference strains from other geographic regions.

Findings and Conclusion

• The study confirmed the presence of this parasite in equids from Türkiye. Furthermore, the existence of these hydatid cysts in the animals strengthens the hypothesis that the parasite may indeed be zoonotic.
• The study underscores the necessity for targeted surveillance to thoroughly understand its distribution, transmission, and relevance to zoonotic diseases, especially in light of the first human case reported in Türkiye in 2021.