Prevalence of tick-borne pathogens in ixodid ticks collected from domestic animals in southeast Iran.

BACKGROUND

Tick-borne pathogens (TBPs) pose a significant threat to livestock production in Kerman Province, Iran. Despite the high prevalence of TBPs, our understanding of specific pathogens circulating within local tick populations remains limited. Furthermore, the potential for co-infections with multiple microorganisms complicates the diagnosis and disease management. This study aimed to investigate the prevalence of TBPs in ticks collected from domestic animals in Kerman province using real-time quantitative PCR (qPCR).

METHODS

Tick collection was conducted between April and June 2022 from 199 domestic animals (63 cattle, 63 sheep, 63 goats, and 10 dogs) across 65 villages in three counties of Kerman Province, Iran. Collected ticks were subjected to qPCR assays targeting Coxiella burnetii, Bartonella spp., Rickettsia spp., Francisella spp., Borrelia spp., and Ehrlichia spp. Phylogenetic analysis of the amplified DNA sequences was performed to elucidate the genetic relationships among the detected pathogens.

RESULTS

In this study, 707 ixodid ticks was collected included Hyalomma marginatum marginatum (70.7%, 108 pools) and Rhipicephalus linnaei (29.2%, 27 pools). Based on molecular analysis, Rickettsia spp., Ehrlichia spp, C. burnetii and Bartonella spp. were detected in 55.5%, 9.6%, 8.1% and 0.7%, respectively. Rickettsia aeschlimannii, R. sibirica, R. conorii subsp. israelensis and R. africae were identified based on sequencing and phylogenetical analysis.Co-infections were also observed: 5.9% of the pools (8 pools) were co-infected with Ehrlichia spp. and Rickettsia spp., 3.7% (5 pools) with Rickettsia spp. and C. burnetii, and 0.7% (1 pool) with Rickettsia spp. and Bartonella spp. No infections with Francisella spp. or Borrelia spp. were detected.

CONCLUSIONS

This study demonstrates the presence of multiple tick-borne pathogens of veterinary and public health significance in ruminants from Kerman Province, highlighting the need for further research on tick-borne diseases affecting both animal and human populations in this and surrounding regions.