Seroprevalence and Molecular Detection of Toxoplasma gondii in Wild Boars (Sus scrofa) in Khuzestan Province, Iran

Zoonoses Public Health. 2024 Dec 2. doi: 10.1111/zph.13195. Online ahead of print.

Abstract

Introduction: Toxoplasma gondii is a parasitic protozoan capable of infecting warm-blooded animals, including humans, and is the causative agent of toxoplasmosis. Wild boars (Sus scrofa) serve as reservoirs for zoonotic pathogens like T. gondii, which can cause disease in humans if transmitted. This study aimed to assess the seroprevalence and molecular prevalence of T. gondii in wild boars in Khuzestan Province, Iran.

Methods: Seroprevalence of T. gondii antibodies was assessed using enzyme-linked immunosorbent assay (ELISA), employing a commercial kit (Calbiotech), whereas molecular detection was carried out through polymerase chain reaction (PCR) targeting the B1 gene of T. gondii on tissue samples (tongue, muscle, diaphragm and heart). Thirty wild boars were sampled from the regions of Shush, Shushtar, Dezful and Abadan, and both blood and tissue samples were analysed.

Results: In this study, the seroprevalence of T. gondii antibodies was found to be 83.3% (25/30) among wild boar serum samples using ELISA. Molecular detection through PCR identified T. gondii DNA in 46.7% (14/30) of tissue samples, with the highest detection rates in tongue tissues (64%), followed by muscle (21%) and diaphragm (14%). No positive results were found in heart samples, and no animal had multiple tissues testing positive. All PCR-positive cases corresponded with positive ELISA results, and a statistically significant difference was observed in parasite prevalence across different tissues (p = 0.002).

Conclusion: Although consumption of wild boar meat is banned in Iran, illegal hunting and consumption remain a concern. The high prevalence of T. gondii in wild boars poses a potential risk for transmission through the illegal consumption of undercooked or raw meat. This study highlights the need for public health interventions to control the illegal trade of wild boar meat and reduce the risk of toxoplasmosis transmission. Further research is recommended to investigate T. gondii distribution in other tissues, including the brain, and to better understand the parasite's epidemiology in this region.

Keywords: Toxoplasma gondii; molecular detection; seroprevalence; wildlife; zoonotic pathogens.