Molecular evidence for Toxoplasma gondii in feeding and questing Ixodes ricinus ticks.

This research study sought to identify the presence of Toxoplasma gondii in ticks that were collected from Shetland ponies and surrounding fields. The study found evidence of T. gondii in approximately 4.5% of ticks, suggesting that the ponies probably are not a primary host for the organism.

Research Scope and Methodology

• The research aimed to detect the presence of Toxoplasma gondii, a parasite, in two types of ticks: feeding Ixodes ricinus collected from Shetland ponies and questing ticks collected from field vegetation.
• The study also aimed to determine if Shetland ponies could be a reservoir host for T. gondii.
• A total of 1737 feeding ticks and 371 questing ticks were collected and tested for T. gondii using PCR and sequencing.
• All the ticks were analyzed in a prior study to detect and identify pathogenic bacterial species, with this study exploring the possibility of co-infection.

Key Findings

• The B1 gene of the T. gondii strains was sequenced, revealing that the detected strains represented genotype I, a type which is pathogenic to humans.
• T. gondii genotype I was present in 4.5% of I. ricinus ticks, including 2.99% of feeding ticks and 10.24% of questing ticks. The significant difference in these percentages led to the conclusion that ponies probably are not an essential host for this sporozoan.
• Infections that involved multiple pathogenic species were rare, but when they occurred, it was predominantly T. gondii and Borrelia burgdorferi sensu lato.
• Ultimately, the results not only confirmed the presence of T. gondii in I. ricinus but also indicated a new geographical habitat: this was the first detection of T. gondii in I. ricinus ticks in Poland.